Tia Cissp
262 questions across 0 topics. Use the find bar or section chips to jump to what you need.
Application: HTTP, FTP, LPD, SMTP, Telnet, TFTP, EDI, POP3, IMAP, SNMP, NNTP, S-RPC, and SET Presentation: Encryption protocols and format types, such as ASCII, EBCDICM, TIFF, JPEG, MPEG, MIDI Sessions: NFS, SQL, and RPC Transport: SPX, SSL, TLS, TCP, and UDP Network: ICMP, RIP, OSPF, BGP, IGMP, IP, IPSec, IPX, NAT, and SKIP Data Link: SLIP, PPP, ARP, L2F, L2TP, PPTP, FDDI, ISDN Physical: EIA/ TIA-232, EIA/TIA-449, X.21, HSSI, SONET, V.24, and V.35
Exam Essentials: Know the OSI model layers and which protocols are found in each.
Know the difference between TCP and UDP; be familiar with the four TCP/IP layers (Application, Transport, Internet, and Link) and how they correspond to the OSI model. In addition, understand the usage of the well-known ports and be familiar with the subprotocols.
Exam Essentials: Have a thorough knowledge of TCP/ IP
This include STP, 10BaseT (UTP), 10Base2 (thinnet), 10Base5 (thicknet), 100BaseT, 1000BaseT, and fiber-optic. You should also be familiar with UTP categories 1 through 7.
Exam Essentials: Know the different cabling types and their lengths and maximum throughput rates
The most common LAN technology is Ethernet. Also be familiar with analog vs. digital communications; synchronous vs. asynchronous communications; baseband vs. broadband communications; broadcast, multicast, and unicast communications; CSMA, CSMA/CA, and CSMA/CD; token passing; and polling
Exam Essentials: Be familiar with the common LAN technologies
Network security should take into account IP and non-IP protocols, network access control, using security services and devices, managing multilayer protocols, and implementing endpoint security.
Exam Essentials: Understand secure network architecture and design
Network segmentation can be used to managed traffic, improve performance, and enforce security. Examples of network segments or subnetworks include intranet, extranet, and DMZ.
Exam Essentials: Understand the various types and purposes of network segmentation.
Cell phones, Bluetooth (802.15), and wireless networking (802.11) are all called wireless technologies, even though they are all different. Be aware of their differences, strengths, and weaknesses. Understand the basics of securing 802.11 networking.
Exam Essentials: Understand the different wireless technologies.
Fibre Channel is a form of network data storage solution (i.e., SAN (storage area network) or NAS (network-attached storage)) that allows for high-speed file transfers.
Exam Essentials: Understand Fibre Channel
FCoE (Fibre Channel over Ethernet) is used to encapsulate Fibre Channel communications over Ethernet networks.
Exam Essentials: Understand FCoE
iSCSI (Internet Small Computer System Interface) is a networking storage standard based on IP.
Exam Essentials: Understand iSCSI
802.11 is the IEEE standard for wireless network communications. Versions include 802.11 (2 Mbps), and 802.11a (54 Mbps), 802.11 (11 Mpbs), 802.11g (54 Mbps), 802.11n (600 Mbps), and 802.11ac (1.3+ Mbps). The 802.11 standard also defines Wired Equivalent Privacy (WEP).
Exam Essentials: Understand 802.11 and 802.11a, b, g, n, and ac
A site survey is the process of investigating the presence, strength, and reach of wireless access points deployed in an environment. This task usually involves walking around with a portable wireless device, taking note of the wireless signal strength, and mapping this on a plot or schematic of the building.
Exam Essentials: Understand site survey
WPA2 is a new encryption scheme known as the Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP), which is based on the AES encryption scheme
Exam Essentials: Understand WPA2
EAP (Extensible Authentication Protocol) is not a specific mechanism of authentication; rather it is an authentication framework. Effectively, EAP allows for new authentication technologies to be compatible with existing wireless or point-to-point connection technologies.
Exam Essentials: Understand EAP
PEAP (Protected Extensible Authentication Protocol) encapsulates EAP methods within a TLS tunnel that provides authentication and potentially encryption.
Exam Essentials: Understand PEAP
LEAP (Lightweight Extensible Authentication Protocol) is a Cisco proprietary alternative to TKIP for WPA. This was developed to address deficiencies in TKIP before the 802.11i/ WPA2 system was ratified as a standard.
Exam Essentials: Understand LEAP
A MAC filter is a list of authorized wireless client interface MAC addresses that is used by a wireless access point to block access to all nonauthorized devices.
Exam Essentials: Understand MAC Filtering
Wireless networks traditionally announce their SSID on a regular basis within a special packet known as the beacon frame. When the SSID is broadcast, any device with an automatic detect and connect feature is not only able to see the network, but it can also initiate a connection with the network.
Exam Essentials: Understand SSID Broadcast
TKIP (Temporal Key Integrity Protocol) was designed as the replacement for WEP without requiring replacement of legacy wireless hardware. TKIP was implemented into 802.11 wireless networking under the name WPA (Wi-Fi Protected Access).
Exam Essentials: Understand TKIP
CCMP (Counter Mode with Cipher Block Chaining Message Authentication Code Protocol) was created to replace WEP and TKIP/ WPA. CCMP uses AES (Advanced Encryption Standard) with a 128-bit key.
Exam Essentials: Understand CCMP
A captive portal is an authentication technique that redirects a newly connected wireless web client to a portal access control page.
Exam Essentials: Understand captive portals
A wide variety of antenna types can be used for wireless clients and base stations. These include omnidirectional pole antennas as well as many directional antennas, such as Yagi, cantenna, panel and parabolic.
Exam Essentials: Understand antenna types
These are ring, bus, star, and mesh.
Exam Essentials: Know the standard network topologies
Common network devices are firewalls, routers, hubs, bridges, modems, repeaters, switches, gateways, and proxies.
Exam Essentials: Know the common network devices
There are several types of firewalls: static packet filtering, application-level gateway, circuit-level gateway, stateful inspection, deep-packet inspection, and next-gen.
Exam Essentials: Understand the different types of firewalls
These are Frame Relay, SMDS, X.25, ATM, HSSI, SDLC, HDLC, and ISDN.
Exam Essentials: Know the protocol services used to connect to LAN and WAN communication technologies
Application (7) Presentation (6) Session (5) Transport (4) Network (3) Data Link (2) Physical (1)
Written Lab: Name the layers of the OSI model and their numbers from top to bottom.
Problems with cabling and their countermeasures include attenuation (use repeaters or don't violate distance recommendations), using the wrong CAT cable (check the cable specifications against throughput requirements, and err on the side of caution), crosstalk (use shielded cables, place cables in separate conduits, or use cables of different twists per inch), cable breaks (avoid running cables in locations where movement occurs), interference (use cable shielding, use cables with higher twists per inch, or switch to fiber-optic cables), and eavesdropping (maintain physical security over all cable runs or switch to fiber-optic cables).
Written Lab: Name three problems with cabling and the methods to counteract those issues.
Some of the frequency spectrum-use technologies are spread spectrum, Frequency Hopping Spread Spectrum (FHSS), Direct Sequence Spread Spectrum (DSSS), and Orthogonal Frequency-Division Multiplexing (OFDM).
Written Lab: What are the various technologies employed by wireless devices to maximize their use of the available radio frequencies?
Methods to secure 802.11 wireless networking include disabling the SSID broadcast; changing the SSID to something unique; enabling MAC filtering; considering the use of static IPs or using DHCP with reservations; turning on the highest form of encryption offered (such as WEP, WPA, or WPA2/802.11i); treating wireless as remote access and employing 802.1X, RADIUS, or TACACS; separating wireless access points from the LAN with firewalls; monitoring all wireless client activity with an IDS; and considering requiring wireless clients to connect with a VPN to gain LAN access.
Written Lab: Discuss methods used to secure 802.11 wireless networking.
The LAN shared media access technologies are CSMA, CSMA/CA (used by 802.11 and AppleTalk), CSMA/CD (used by Ethernet), token passing (used by Token Ring and FDDI/ CDDI), and polling (used by SDLC, HDLC, and some mainframe systems).
Written Lab: Name the LAN shared media access technologies and examples of their use, if known.
Remote access security management requires that security system designers address the hardware and software components of an implementation along with issues related to policy, work tasks, and encryption.
Exam Essentials: Understand the issues around remote access security management
These are SKIP, SWIPE, SLL, SET, PPP, SLIIP, CHAP, PAP, EAP, and S-RPC. They can also include VPN, TLS/SSL, and VLAN.
Exam Essentials: Be familiar with the various protocols and mechanisms that may be used on LANs and WANs for data communications.
Tunneling is the encapsulation of a protocol-deliverable message within a second protocol. The second protocol often performs encryptions to protect that message contents.
Exam Essentials: Know what tunneling is
VPNs are based on encrypted tunneling. They can offer authentication and data protection as a point-to-point solution. Common VPN protocols are PPTP, L2F, L2TP, and IPsec.
Exam Essentials: Understand VPNs
NAT protects the addressing scheme of a private network, allows the use of the private IP addresses, and enables multiple internal clients to obtain internet access through a few public IP addresses. NAT is supported by many security border devices, such as firewalls, routers, gateways, and proxies.
Exam Essentials: Be able to explain NAT
In circuit switching, a dedicated physical pathway is created between the two communicating parties. Packet switching occurs when the message or communication is broken up into small segments and sent across the intermediary networks to the destination. Within packet-switching systems are two types of communication paths, or virtual circuits: permanent virtual circuits (PVCs) and switched virtual circuits (SVCs).
Exam Essentials: Understand the difference between packet switching and circuit switching
A dedicated line is always on and is reserved for a specific customer. Examples of dedicated lines include T1, T3, E1, E3, and cable modems. A nondedicated line requires a connection to be established before data transmission can occur. It can be used to connect with any remote system that uses the same type of nondedicated line. Standard modems, DSL, and ISDN are examples of nondedicated lines.
Exam Essentials: Understand the difference between dedicated and nondedicated lines
Be familiar with remote access, dial-up connections, screen scrapers, virtual applications/ desktops, and general telecommuting security concerns
Exam Essentials: Know various issues related to remote access security
Know that most WAN technologies require a channel service unit/data service unit (CSU/DSU), sometimes called a WAN (switch0. Three are many types of carrier networks and WAN connection technologies require additional specialized protocols to support various types of specialized systems or devices.
Exam Essentials: Know the various types of WAN technologies
The Point-to-Point Protocol (PPP) is an encapsulation protocol designed to support the transmission of IP traffic over dial-up or point-to-point links. PPP includes a wide range of communication services, including assignment and management of IP addresses, management of synchronous communications, standardized encapsulation, multiplexing, link configuration, link quality testing, error detection, and feature or option negotiation (such as compression). PPP was originally designed to support CHAP and PAP for authentication. However, recent versions of PPP also support MS-CHAP, EAP, and SPAP. PPP replaced Serial Line Internet Protocol (SLIP). SLIP offered no authentication, supported only half-duplex communications, had no error-detection capabilities, and required manual link establishment and teardown.
Exam Essentials: Understand the differences between PPP and SLIP
Security controls should be transparent to users. Hash totals and CRC checks can be used to verify message integrity. Record sequences are used to ensure sequence integrity of a transmission. Transmission logging helps detect communication abuses.
Exam Essentials: Understand common characteristics of security controls
Internet email is based on SMTP, POP3, and IMAP. It is inherently insecure. It can be secured, but the methods used must be addressed in a security policy. Email security solutions include using S/MIME, MOSS, PEM, and PGP.
Exam Essentials: Understand how email security works
Fax security is primarily based on using encrypted transmissions or encrypted communication lines to protect the faxed materials. The primary goal is to prevent interception. Activity logs and exception reports can be used to detect anomalies in fax activity that could be symptoms of attack.
Exam Essentials: Know how fax security works
Countermeasures to PBX fraud and abuse include many of the same precautions you would employ to protect a typical computer network: logical or technical controls, administrative controls, and physical controls.
Exam Essentials: Know the threats associated with PBX systems and the countermeasures to PBX fraud.
VoIP is at risk for caller ID spoofing, vishing, SPIT, call manager software/ firmware attacks, phone hardware attacks, DoS, MitM, spoofing, and switch hopping.
Exam Essentials: Understand the security issues related to VoIP
Phreaking is a specific type of attack in which various types of technology are used to circumvent the telephone system to make free long-distance calls, to alter the function of telephone service, to steal specialized services, or even to cause service disruptions. Common tools of phreakers include black, red, blue, and white boxes.
Exam Essentials: Recognize what a phreaker is
Voice communications are vulnerable to many attacks, especially as voice communications become an important part of network services. You can obtain confidentiality by using encrypted communications. Countermeasures must be deployed to protect against interception, eavesdropping, tapping, and other types of exploitation. Be familiar with voice communication topics, such as POTS, PSTN, PBX, and VoIP.
Exam Essentials: Understand voice communications security
Social engineering is a means by which an unknown person gains the trust of someone inside your organization by convincing employees that they are, for example, associated with upper management, technical support, or the help desk. The victim is often encouraged to make a change to their user account on the system, such as reset their password, so the attacker can use it to gain access to the network. The primary countermeasure for this sort of attack is user training.
Exam Essentials: Be able to explain what social engineering is
A security boundary can be the division between one secured area and another secured area. It can also be the division between a secured area and an unsecured area. Both must be addressed in a security policy.
Exam Essentials: Explain the concept of security boundaries
Communication systems are vulnerable to many attacks, including distributed denial of service (DDoS), eavesdropping, impersonation, replay, modification, spoofing, and APR and DNS attacks. Be able to supply effective countermeasures for each.
Exam Essentials: Understand the various network attacks and countermeasures associated with communications security.
IPsec's transport mode is used for host-to-host links and encrypts only the payload, not the header. IPsec's tunnel mode is used for host-to-LAN and LAN-to-LAN links and encrypts the entire original payload and header and then adds a link header.
Written Lab: Describe the differences between transport mode and tunnel mode of IPsec.
Network Address Translation (NAT) allows for the identity of internal systems to be hidden from external entities. Often NAT is used to translate between RFC 1918 private IP addresses and leased public address. NAT serves as a one-way firewall because it allows only inbound traffic that is a response to a previous internal query. NAT also allows a few leased public addresses to be used to grant internet connectivity to a larger number of internal systems.
Written Lab: Discuss the benefits of NAT.
Circuit switching is usually associated with physical connections. The link itself is physically established and then dismantled for the communication. Circuit switching offers known fixed delays, supports constant traffic, is connection oriented, is sensitive only to the loss of the connection rather than the communication, and was most often used for voice transmissions. Packet switching is usually associated with logical connections because the link is just a logically defined path among possible paths. Within a packet-switching system, each system or link can be employed simultaneously by other circuits. Packet switching divides the communications into segments, and each segment traverses the circuit to the destination. Packet switching has variable delays because each segment could take a unique path, is usually employed for bursty traffic, is not physically connection oriented but often use virtual circuits, is sensitive to the loss of data, and is used for any form of communication.
Written Lab: What are the main differences between circuit switching and packet switching?
Email is inherently insecure because it is primarily a plaintext communication medium and employs non-encrypted transmission protocols. This allows for email to be easily spoofed, spammed, flooded, eavesdropped on, interfered with, and hijacked. Defenses against these issues primarily include having stronger authentication requirements and using encryption to protect the content while in transit.
Written Lab: What are some security issues with email and options for safeguarding against them?
local area network (Source: Dummies)
A _________________________________ is a data network that operates across a relatively small geographic area, such as a single building or floor. A ________ connects workstations, servers, printers, and other devices so that network resources, such as files and email, can be shared. Key characteristics: - Can connect networked resources over a small geographic area, such as a floor, a building, or a group of buildings. - Are relatively inexpensive to set up and maintain, typically consisting of readily available equipment such as servers, desktop PCs, printers, switches, hubs, bridges, repeaters, wireless access points (WAPs or simply, APs), and various security devices such as firewalls and intrusion prevention systems (IPSs). - Can be wired, wireless, or a combination of both wired and wireless. - Perform at relatively high speeds- typically 10 megabits per second (Mbps), 100 Mbps, 1000 Mbps (also referred to as 1 gigabit per second [1 Gbps]), 10 Gbps, and 40 Gbps for wired networks, and 11 Mbps, 54 Mbps, or 600 Mbps for wireless networks. *Hint: Same term for all blanks
DUMMIES WARNING: Be careful when referring to data capacity (and their abbreviations) and data storage. 100 Mbps is "100 megabits per second," and 100 MB is "100 megabytes." The distinction is subtle (a little b versus a big B, bits rather than bytes), but the difference is significant: A byte is equal to 8 bits. Data speeds are typically referred to in bits per second; data storage is typically referred to in bytes.
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A local area network (LAN) is a data network that operates across a relatively small geographic area, such as a building or group of buildings.
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wide area network
A ___________________________ connects multiple LANs and other WANs by using telecommunications devices and facilities to form an internetwork. Key characteristics of WANs include the following: - Connect multiple LANs over large geographic areas, such as a small city (for example, a metropolitan area network ([for MAN]), a region or country, a global corporate network, the entire planet (for example, the Internet), or beyond (for example, the International Space Station via satellite). - Can relatively expensive to set up and maintain, typically consisting of equipment such as routers, Channel Service Unit/ Data Service Unit (CSU/ DSU) devices, firewalls, virtual private network (VPN) concentrators, and various other security devices. - Perform at relatively low speeds by using various technologies, such as dial-up (56 kilobits per second [Kbps]); digital subscriber line, or DSL (approximately 45 Mbps); OC-12 (approximately 622 Mbps); and OC-255 (approximately 13 Gbps).
- Internet: The mother of all WANs, the Internet is the global network of public networks originally developed by the U.S. Department of Defense (DoD) Advanced Research Projects Agency (DARPA). Users and systems connect to the Internet via Internet service providers (ISPs). - Intranet: An intranet can be thought of as a private Internet. An intranet typically uses web-based technologies to disseminate company information that's available only to authorized users on an internal company network. - Extranet: An extranet extends the basic concept of an intranet to include partners, vendors, or other related parties. For example, an automobile manufacturer may operate an extranet that connects networks belonging to parts manufacturers, distributors, and dealerships. Extranets are commonly operated across the Internet by using a virtual private network (VPN) or other secure connection.
List some examples of WANs:
wide area network (WAN)
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- Clarifies the general functions of a communication process, instead of focusing on specific issues. - Reduces complex networking processes into simpler sub-layers and components - Promotes interoperability by defining standard interfaces - Aids development by allowing vendors to change individual features at a single layer, instead of rebuilding the entire protocol stack. - Facilitates easier (and more logical) troubleshooting.
The OSI & TCP/IP models define standard protocols for network communication and interoperability by using a layered approach. This approach divides complex networking issues into simpler functional components that help the understanding, design, and development of networking solutions and provides the following specific advantages: (?)
Personal area network (PAN) and wireless personal area network (WPAN)
Connects an individual's electronic devices to each other or to a larger network, such as the Internet and the Internet of Things (IoT). Examples of devices that might be connected via a PAN include laptop computers, smartphones, tablets, wearable technology, virtual personal assistants (such as Amazon Alexa, Apple Siri, Google Assistant, and Microsoft Cortana) home appliance, smart thermostats, and home security cameras. These devices can be connected via wired technologies such as USB and FireWire, or wireless technologies such as Wi-Fi, Bluetooth, IrDA (Infrared Data Associate), 6LoWPAN (IPv6 over Lower power Wireless Personal Area Networks), Bluetooth Low-Energy (BLE, also known as Bluetooth Smart of Bluetooth 4.0+), Bluetooth Mesh, Threat, ZigBee, and Open Connectivity Foundation (OCF). A wireless PAN is also sometimes referred to as a WPAN.
Storage area network (SAN)
Connects servers to a separate physical storage device (typically a disk array). The server operating system sees the storage as if it were directly attached to the server, SANs typically comprise several terabytes or more of disk storage and incorporate highly sophisticated design architectures for fault tolerance and redundancy. Communications protocols used in SANs typically include SCSI (Small Computer System Interface, pronounced "Scuzzy"), iSCI (IP-based SCSI), Fibre Channel Protocol (FCP, SCSI over Fibre Channel), and FCoE (Fibre Channel over Ethernet). SANs are highly scalable, enable technologies such as virtualization and snapshots, provide flexibility in server deployment options, facilitate disaster recovery (for example, with real-time replication), and tried to reduce the overall cost of data storage.
Virtual local area network (VLAN)
Implemented on network switches in a LAN as a way of logically grouping users and resources in a broadcast domain. Often, such VLANs correlate to department functions (such as Accounting, Sales, and Research & Development) and/ or IP subnets. VLANs provide scalability, segmentation, and (some) security at Layer 2 and can also work to limit the size of your Ethernet broadcast domains. VLANs are implemented by using Institute of Electrical and Electronics Engineers (IEEE) 802.1q tagging to tag Ethernet frames with VLAN information. Note: the IEEE is an international organization that defines many standards, including numerous 802 networking standards.
Wireless local area network (WLAN)
Also known as Wi-Fi network. A wireless LAN that uses wireless access points (WAPs, or simply APs) to connect wireless-enabled devices to a wired LAN.
Wireless wide are network (WWAN)
A wireless network that typically uses mobile cellular technologies such as 4G Long-Term Evolution (LTE), Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), or Code Division Multiple Access (CDMA2000), to extend wireless network coverage regionally, nationally, and/ or globally.
Campus area network (CAN) and wireless campus area network (WCAN)
Connects multiple buildings across a high-performance backbone.
Metropolitan area network (MAN) and wireless metropolitan area network (WMAN)
Extends across a large area, such as a small city.
Value-added network (VAN)
A type of extranet that allows businesses within an industry to share information or integrate shared processes. For example, Electronic Data Interchange (EDI) allows organizations to exchange structured documented- such as order forms, purchase orders, bills of lading, and invoices- over a secure network.
Open Systems Interconnection (OSI) Reference Model (or simply, the OSI model)
In 1984, the International Organization for Standardization (ISO) adopted the ____________________________________ to facilitate interoperability between network devices independent of the manufacturer. - consists of 7 distinct layers that describe how data is communicated between systems and applications on a computer network
- Application (Layer 7) - Presentation (Layer 6) - Session (Layer 5) - Transport (Layer 4) - Network (Layer 3) - Data Link (Layer 2) - Physical (Layer 1)
List the layers (in order from Layer 7 to Layer 1) of the OSI model:
Try creating a mnemonic to recall the layers of the OSI model, such as All People Seem To Need Delicious Pizza, and in reverse, Please Do Not Throw Sausage Pizza Away.
Dummies Tip - Flip the card!
data encapsulation
Each layer communicates only with the layer immediately above and below it (adjacent layers). This communication is achieved through a process known as _______________________________. ___________________________ wraps protocol information from the layer immediately above in the data section of the layer immediately from the layer immediately above in the data section of the layer immediately below.
Application Layer (Layer 7)
The _______________________________ is the highest layer of the OSI model. It supports the components that deal with the communication aspects of an application that requires network access, and it provides an interface to the user. So, both the _________________ layer and the end-user itneract directly with the application. This layer is responsible for: - Identifying and establishing availability of communication partners - Determining resource availability - Synchronizing communication
The Application Layer is responsible for identifying and establishing availability of communication partners, determining resource availability, and synchronizing communication.
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This layer is responsible for: - Identifying and establishing availability of communication partners - Determining resource availability - Synchronizing communication
What is the Application Layer responsible for?
- File transfer protocol (FTP) - HyperText Transfer Protocol (HTTP) - HyperText Transfer Protocol Secure (HTTPS) - Internet Message Access Protocol (IMAP) - Post Office Protocol Version 3 (POP3) - Privacy Enhanced Mail (PEM) - Secure Hypertext Transfer Protocol (S-HTTP) - Secure Multipurpose Internet Mail Extensions (S/MIME) - Simple Mail Transfer Protocol (SMTP) - Simple Network Management Protocol (SNMP) - Telnet - Trivial File Transfer Protocol (TFTP)
Applications that function at the Application Layer include:
File transfer protocol (FTP)
A program used to copy files from one system to another over a network. ________ operates on TCP ports 20 (the data port) and 21 (the control port).
HyperText Transfer Protocol (HTTP)
The language of the World Wide Web (WWW), used by web servers and browsers for non-sensitive content. ______ operates on TCP port 80.
HyperText Transfer Protocol Secure (HTTPS)
The language of commercial transactions on the World Wide Web (WWW). ________________ is actually the HTTP protocol used in combination with SSL/ TLS. _________ operates on TCP port 443, but occasionally on other ports such as 8443. *Hint: same term for all blanks
Internet Message Access Protocol (IMAP)
A store-and-forward electronic mail protocol that allows an email client to access, manage, and synchronize email on a remote mail server. ___________ provides more functionality and security than POP3, such as requiring users to explicitly delete emails from the server. The most current version is IMAPv4 (or IMAP4), which operates on TCP and UDP port 143. Email clients that use ___________ can be secured by using TLS or SSL encryption over TCP/ UDP port 993.
Post Office Protocol 3 (POP3)
An email retrieval protocol that allows and email client to access email on a remote mail server by using TCP port 110. Inherently insecure, ________ allows users to authenticate over the Internet by using plaintext passwords. Email clients that use POP3 can be secured by using TLS or SSL encryption over TCP/ UDP port 995.
Privacy Enhanced Mail (PEM)
______________ is an IETF (Internet Engineering Task Force) standard for providing email confidentiality and authentication. ________ is not widely used. *Hint: term is the same for all blanks
Secure HyperText Transfer Protocol (S-HTTP)
______________ is an Internet protocol that provides a method for secure communications with a web server. ___________ is a connectionless-oriented protocol that encapsulates data after security properties for the session have been successfully negotiated. *Hint: term is the same for all blanks
Do not confuse HTTPS and S-HTTP. They are two distinctly different protocols with several differences. For example, HTTPS encrypts an entire communications session and is commonly used in VPNs, whereas S-HTTP encrypts individual messages between a client and server pair.
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Secure Multipurpose Internet Mail Extensions (S/MIME)
___________ is a secure method of sending email incorporated into several popular browsers and email applications.
Simple Mail Transfer Protocol (SMTP)
Used to send a receive email across the Internet. This protocol has several-well known vulnerabilities that make it inherently insecure. _________ operates on TCP/ UDP port 25. ________ over SSL/ TLS (SMTPS) uses TCP/ UDP port 465. *Hint: term is the same for all blanks
Simple Network Management Protocol (SNMP)
Used to collect network information by polling stations and sending traps (or alerts0 to a management station. __________ has many well-known vulnerabilities, including default cleartext community strings (passwords). ______ operates on TCP/UDP ports 161 (agent) and 162 (manager). Secure ______ uses TCP/UDP ports 10161 (agent) and 10162 (manager). *Hint: term is the same for all blanks
Telnet
Provides terminal emulation for remote access to system resources. ______________ operates on TCP/UDP port 23. Because ___________ transmits passwords in cleartext, it is no longer considered safe; instead SSH is preferred. *Hint: term is the same for all blanks
Trivial File Transfer Protocol (TFTP)
A lean, mean version of FTP without directory-browsing capabilities or user authentication. Generally considered less secure than FTP, _____________ operates on UDP port 69.
Presentation Layer (Layer 6)
The ______________________________________ provides coding and conversion functions that are applied to data being presented to the Application Layer (Layer 7). These functions ensure that data sent from the Application Layer of one system are compatible with the Application Layer of receiving system.
The Presentation Layer is responsible for coding and conversion functions.
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Presentation Layer is responsible for coding and conversion functions.
What is the Presentation Layer responsible for?
- Data representation: Use of common data representation formats (standard image, sound, and video formats) enable application data to be exchanged between different types of computer systems. - Character conversion: Information is exchanged between different systems by using common character conversion schemes. - Data compression: Common data compression schemes enable compressed data to be properly decompressed at the destination. - Data encryption: Common data encryption schemes enable encrypted data to be properly decrypted at the destination.
What are the tasks associated with the Presentation Layer?
- American Standard Code for Information Interchange (ASCII) - Extended Binary-Coded Decimal Interchange Code (EBCDIC) - Graphics Interchange Format (GIF) - Joint Photographic Experts Group (JPEG) - Motion Picture Experts Group (MPEG)
What are some examples of the Presentation Layer?
American Standard Code for Information Interchange (ASCII)
a character-encoding scheme based on the English alphabet, consisting of 128 characters
Extended Binary-Coded Decimal Interchange Code (EBCDIC)
an 8-bit character-encoding scheme largely used on mainframe and mid-range computers
Graphics Interchange Format (GIF)
a widely used bitmap image format that allows up to 256 colors and is suitable for images or logos (but not photographs)
Joint Photographic Experts Group (JPEG)
a photographic compression method widely used to store and transmit photographs
Motion Picture Experts Group (MPEG)
an audio and video compression method widely used to store and transmit audio and video files
Session Layer (Layer 5)
The ____________________________ establishes, coordinates, and terminates communication sessions (service requests and service responses) between networked system.
The Session Layer is responsible for establishing, coordinating, and terminating communication sessions between systems.
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Session Layer is responsible for establishing, coordinating, and terminating communication sessions between systems.
What is the Session Layer responsible for?
- Connection establishment - Data transfer - Connection release
A communication session is divided into what three distinct phases?
Connection establishment
Initial contact between communicating systems is made, and the end devices agree on communications parameters and protocols to be used including the mode of operation (Simplex mode, Half-duplex mode, Full-duplex mode).
Simplex mode
In __________________ mode, a one-way communications path is established with a transmitter at one end of the connection and a receiver at the other end. An analogy is AM radio, where a radio station broadcasts music and the radio receiver can only receive the broadcast.
Half-duplex mode
In ____________________ mode, both communicating devices are capable of transmitting and receiving messages, but they can't do it at the same time. An analogy is a two-way radio in which a button must be pressed to transmit and then released to receive a signal.
Full-duplex mode
In ___________________ mode, both communicating devices are capable of transmitting and receiving simultaneously. An analogy is a telephone with which you can transmit and receive signals (but not necessarily communicate) at the same time.
Data transfer
information is exchanged between end devices
Connection release
after data transfer is completed, end devices systematically end the session
- NetBIOS - Network File System (NFS) - Remote Procedure Call (S-RPC) - Secure Shell (SSH and SSH-2) - Session Initiation Protocol (SIP)
What are some examples of protocols in a Session Layer?
Network Basic Input/ Output System (NetBIOS)
__________________________________________ is a Microsoft protocol that allows applications to communicate over a LAN. When ______________ is combined with other protocols such as TCP/IP, known as _________ over TCP/IP (or NBT), applications can communicate over large networks. *Hint: same term for all the blanks
Network File System (NFS)
developed by Sun Microsystems to facilitate transparent user access to remote resources on a UNIX-based TCP/IP network
Remote Procedure Call (RPC)
A client-server network redirection tool. Procedures are created on clients and performed on servers.
Secure Remote Procedure Call (S-RPC)
__________ is a secure client-server protocol that's defined at multiple upper layers of the OSI model. RPC is used to request services from another computer on the network. ___________ provides public and private keys to clients and servers by using Diffie-Hellman. After ______ operations initially authenticate, they're transparent to the end-user. *Hint: same term for all the blanks
Secure Shell (SSH and SSH-2)
________ provides a secure alternative to Telnet for remote access. _____ establishes and encrypted tunnel between the client and the server, and can also authenticate the client to the server. ____________ can be used to protect the confidentiality and integrity of network communications. __________-2 establishes an encrypted tunnel between the ______ client and ________ server and can also authenticate the client to the server. _________ version 1 is also widely used but has inherent vulnerabilities that are easily exploited. *Same term/ acronym for all the blanks (one of the blanks is modified so that it is the correct term).
SSH-2 (or simply SSH) is an Internet security application that provides secure remote access.
The Dummies book wants you to remember this! FLIP THE CARD!
Session Initiation Protocol (SIP)
an open signaling protocol standard for establishing, managing and terminating real-time communications- such as voice, video, and text- over large IP-based networks
Transport Layer (Layer 4)
The ______________________________________ provides transparent, reliable data transport and end-to-end transmission control. - Hides the details of the lower layer functions from the upper layers.
- Flow control - Multiplexing - Virtual circuit management - Error checking and recovery
What are the specific transport layer functions include?
flow control
manages data transmission between devices, ensuring that the transmitting device doesn't send more data than the receiving device can process
multiplexing
enables data from multiple applications to be transmitted over a single physical link
virtual circuit management
establishes, maintains, and terminates virtual circuits
error checking and recovery
implements various mechanisms for detecting transmission errors and taking action to resolve any errors that occur, such as requesting that data be retransmitted
The Transport layer is responsible for providing transparent data transport and end-to-end transmission control
The Dummies book wants you to remember this! FLIP THE CARD!
Transport layer is responsible for providing transparent data transport and end-to-end transmission control
What is the Transport Layer responsible for?
- Transmission Control Protocol (TCP) - User Datagram Protocol (UDP) - Sequenced Packet Exchange (SPX) - Secure Sockets Layer/ Transport Layer Security (SSL/ TLS) - Stream Control Transmission Protocol (SCTP)
List several important protocols defined at the Transport Layer:
Transmission Control Protocol (TCP)
A full-duplex (capable of simultaneous transmission and reception), connection-oriented protocol that provides reliable delivery of packets across a network. A connection-oriented protocol requires a direct connection between two communicating devices before any data transfer occurs. In ______, this connection is accomplished via a three-way handshake. The receiving device acknowledges packets, and packets are retransmitted if an error occurs. The following characteristics and features are associated with TCP: Connection-oriented; Reliable; Slow A three-way handshake is the method used to establish a __________ connection. A PC attempting to establish a connection with a server initiates the connection by sending a TCP SYN (Synchronize) packet. This is the first part of the handshake. In the second part of the handshake, the server replies to the PC with a SYN ACK packet (Synchronize Acknowledgement). Finally, the PC completes the handshake by sending an ACK or SYN-ACK-ACK packet, acknowledging the server's acknowledgement, and the data communications comment. A socket is a logical endpoint on a system or device used to communicate over a network to another system or device (or even on the same device). A socket usually is expressed as an IP address and port number, such as 192.168.100.2:25. *Hint: same term/ acronym for all the blanks
A three-way handshake is the method used to establish a TCP connection. A PC attempting to establish a connection with a server initiates the connection by sending a TCP SYN (Synchronize) packet. This is the first part of the handshake. In the second part of the handshake, the server replies to the PC with a SYN ACK packet (Synchronize Acknowledgement). Finally, the PC completes the handshake by sending an ACK or SYN-ACK-ACK packet, acknowledging the server's acknowledgement, and the data communications comment.
Explain a three-way handshake:
socket
A ______________ is a logical endpoint on a system or device used to communicate over a network to another system or device (or even on the same device). A __________________ usually is expressed as an IP address and port number, such as 192.168.100.2:25. *Hint: same term for all the blanks
Three-way handshake is the method used to establish a TCP connection. A PC attempting to establish a connection with a server initiates the connection by sending a TCP SYN (Synchronize) packet. This is the first part of the handshake. In the second part of the handshake, the server replies to the PC with a SYN ACK packet (Synchronize Acknowledgement). Finally, the PC completes the handshake by sending an ACK or SYN-ACK-ACK packet, acknowledging the server's acknowledgement, and the data communications comment.
DUMMIES TECHNICAL NOTE - flip the card!!
The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, the layer 1 PDU is a bit, layer's 2 PDU is a frame, layer's 3's is a packet, and layer 4's is a segment of datagram, and layer 7's PDU.
DUMMIES TECHNICAL NOTE - flip the card!!
A datagram is a self-contained unit of data that is capable of being routed between a source and a destination. Similar to a packet, which is used in the Internet Protocol (IP), datagrams are commonly used in UDP and other protocols.
DUMMIES TECHNICAL NOTE - flip the card!!
Jitter in streaming audio and video is caused by variations in the delay of received packets, which is a negative characteristic of UDP.
DUMMIES TECHNICAL NOTE - flip the card!!
User Datagram Protocol (UDP)
A connectionless protocol that provides fast best-effort delivery of datagrams across a network. A connectionless protocol doesn't guarantee delivery of transmitted packets (datagrams) and is thus considered unreliable. It doesn't: - Attempt to establish a connection with the destination network prior to transmitting data. - Acknowledge received datagrams. - Perform re-sequencing. - Perform error checking or recovery. - A datagram is a self-contained unit of data that is capable of being routed between a source and a destination. Similar to a packet, which is used in the Internet Protocol (IP), datagrams are commonly used in UDP and other protocols. The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, the layer 1 PDU is a bit, layer's 2 PDU is a frame, layer's 3's is a packet, and layer 4's is a segment of datagram, and layer 7's PDU. __________ is ideally suited for data that requires fast delivery, as long as that data isn't sensitive to packet loss and doesn't need to be fragmented. Examples of applications that use _________ include Domain Name System (DNS), Simple Network Management Protocol (SNMP), and streaming audio or video. The following characteristics and features are associated with _________: - Connectionless: Doesn't pre-establish a communication circuit with the destination network. - Best effort: Doesn't guarantee delivery and is thus considered unreliable. - Fast: Has no overhead associated with circuit establishment, acknowledgement, sequencing, or error-checking and recovery. Jitter in streaming audio and video is caused by variations in the delay of received packets, which is a negative characteristic of _________. *Hint: same term for all the blanks
Layer 1 PDU is a bit
The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, the layer 1 PDU is a- (?)
Layer 2 PDU is a frame
The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, layer's 2 PDU is a- (?)
Layer 3's PDU is a packet
The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, layer's 3's is a- (?)
Layer 4's is a segment of datagram
The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, layer 4's is a- (?)
PDU
The term Protocol Data Unit (PDU) is used to describe the unit of data used at a particular layer of a protocol. For instance, in OSI, layer 7's is?
datagram
A _____________________ is a self-contained unit of data that is capable of being routed between a source and a destination. Similar to a packet, which is used in the Internet Protocol (IP), _______________ are commonly used in UDP and other protocols. *Hint: same term for both blanks
Sequenced Packet Exchange (SPX)
The protocol used to guarantee data delivery in older Novell NetWare IPX/SPX networks. SPX sequences transmitted packets, reassembles received packets, confirms all packets are received, and requests retransmission of packets that aren't received. SPX is to IPX as TCP is to IP, though it might be confusing because the order is stated as IPX/SPX, rather SPX/IPX (as in TCP/IP): SPX and TCP are Layer 4 protocols, and IPX and IP are Layer 3 protocols. Just think of it as yang and yin, rather than yin and yang!
- TCP (Transmission Control Protocol), Layer 4 (Transport), Connection-oriented - UDP (User Datagram Protocol), Layer 4 (Transport), Connectionless-oriented - IP (Internet Protocol), Layer 3 (Network), Connectionless-oriented - ICMP (Internet Control Message Protocol), Layer 3 (Network), Connectionless-oriented - IPX (Internetwork Packet Exchange), Layer3 (Network), Connectionless-oriented - SPX (Sequenced Packet Exchange), Layer 4 (Transport), Connection-oriented
Connection-Oriented and Connectionless-Oriented Protocols examples:
Secure Sockets Layer/ Transport Layer Security (SSL/ TLS)
This protocol provides session-based encryption and authentication for secure communication between clients and servers on the Internet. This protocol provides server authentication with optional client authentication.
Stream Control Transmission Protocol (SCTP)
A message-oriented protocol (similar to UDP) that ensures reliable, in-sequence transport with congestion control (similar to TCP). Also provides multi-homing and redundant paths for resiliency and reliability.
Network Layer (Layer 3)
The ______________________________________ provides routing and related functions that enable data to be transported between systems on the same network or on interconnected networks (or internetworks).
Routing; routed
Fill in the blanks: ____________________________ protocols move _____________________ protocol messages across a network.
- Routing Information Protocol (RIP) - Open Shortest Path First (OSPF) - Border Gateway Protocol (BGP) - IS-IS - IGRP
Routing protocols include: (?)
- Internet Protocol (IP) - Internetwork Packet Exchange (IPX)
Routed protocols include: (?)
Routing protocols
_____________________________________ are defined at the Network Layer and specify how routers communicate with one another on a WAN. These protocols are classified as static or dynamic.
static (Source: Techopedia)
_________________ routing is a type of network routing technique. _________________ routing is not a routing protocol; instead, it is the manual configuration and selection of a network route, usually managed by the network administrator. It is employed in scenarios where the network parameters and environment are expected to remain constant. _________________ routing is only optimal in a few situations. Network degradation, latency and congestion are inevitable consequences of the non-flexible nature of _________________ routing because there is no adjustment when the primary route is unavailable. *Hint: Same term for all the blanks
Broadly, routing is performed in two different ways: - Dynamic routing continuously updates its routing table with paths and their cost/metric, while making optimal routing decisions based on changing network operating environments. - Static routing performs routing decisions with preconfigured routes in the routing table, which can be changed manually only by administrators. Static routes are normally implemented in those situations where the choices in route selection are limited, or there is only a single default route available. Also, static routing can be used if you have only few devices for route configuration and there is no need for route change in the future. **Static routing is considered the simplest form of routing. (Source: Techopedia)
Routing is one of the most essential procedures in data communication. It ensures that data travels from one network to another with optimal speed and minimal delay, and that its integrity is maintained in the process. Broadly, routing is performed in two different ways:
dynamic routing protocol
A _________________________ routing protocol can discover routes and determine the best route to a given destination at any given time. The routing table is periodically updated with current routing information. The protocols are further classified as link-state and distance-vector (for intra domain routing) and path-vector (for inter-domain routing) protocols.
distance-vector protocol
A _____________________________ protocol makes routing decisions based on two factors: 1. the distance (hop count or other metric) 2. vector (the egress router interface) It periodically informs its peers and/or neighbors of topology changes. Convergence, the time it takes for all routers in a network to update their routing tables with the most current information (such a link status changes), can be a significant problem for __________________________ protocols. Without convergence, some routers in a network may be unaware of topology changes, causing the router to send traffic to an between routers, and the network slows down considerably. *Hint: same term for both blanks
Routing Information Protocol (RIP)
____________________________________ is a distance-vector routing protocol that uses hop count as its routing metric. In order to prevent routing loops, in which packets effectively get stuck bouncing between various router nodes, _________ implements a hop limit of 15, which significantly limits the size of networks that ________ can support. After a data packet crosses 15 routers nodes (hops) between a source and a destination, the destination is considered unreachable. In addition to hop limits, ________ employs three other mechanisms to prevent routing loops: - Split horizon - Route poisoning - Holddown timers _______ uses UDP port 520 as its transport protocol and port, and thus is a connectionless-oriented protocol. Other disadvantages of ______ include slow convergence and insufficient security (________v1 has no authentication, and _______v2 transmits passwords in cleartext). ______ is a legacy protocol, but it's still in widespread use on networks today, despite its limitations, because of its simplicity. *Hint: same term/ acronym for all the blanks
split horizon
prevents a router from advertising a route back out through the same interface from which the route was learned
route poisoning
sets the hop count on a ad route to 16, effectively advertising the route as unreachable if it takes more than 15 hops to reach
holddown timers
Cause a router to start a timer when the router first receives information that a destination is unreachable. Subsequent updates about that destination will not be accepted until the timer expires. This also helps avoid problems associated with flapping. Flapping occurs when a route (or interface) repeatedly changes state (up, down, up, down) over a short period of time.
Hop count
DUMMIES TECHNICAL STUFF: ______________ generally refers to the number of router nodes that a packet must pass through to reach its destination.
link-state protocol
A ___________________ protocol requires every router to calculate and maintain a complete map, or routing table, of the entire network. Routers that use this protocol periodically transmit updates that contain information about adjacent connections (these are called link states) to all other routers in the network. __________ protocols are computation-intensive but can calculate the most efficient route to a destination, taking into account numerous factors such as link speed, delay, load, reliability, and cost (an arbitrarily assigned weight or metric). Convergence occurs very rapidly (within seconds) with __________ protocols; distance vector protocols usually take longer (several minutes, or even hours in very large networks). Two examples of ________ protocols are: - Open Shortest Path First (OSPF) - Intermediate System to Intermediate System (IS-IS) *Hint: same term/ acronym for all the blanks
Open Shortest Path First (OSPF)
____________________________ is a link-state routing protocol widely used in large enterprise networks. It's considered an Interior Gateway Protocol (IGP) because it performs routing within a single autonomous system (AS). ________ is encapsulated directly into IP datagrams, as opposed to using a Transport Layer protocol such as TCP or UDP. __________ networks are divide3d into areas identified by 32-birt are identifiers. Area identifiers can (but don't have to) correspond to network IP addresses and can duplicate IP addresses without conflicts. Special _________ areas include the backbone area (also known as area 0), stub area, and not-so-stubby area (NSSA). *Hint: same term/ acronym for all the blanks
Intermediate System to Intermediate System (IS-IS)
_____________ is a link-state routing protocol used to route datagrams through a packet-switched network. It is an interior gateway protocol used for routing within an autonomous system, used extensively in large service-provider backbone networks.
autonomous system (AS)
DUMMIES TECHNICAL: An ___________________________ is a group of contiguous IP address rages under the control of a single Internet entity. Individual autonomous systems are assigned a 16-bit or 32-bit AS Number (ASN) that uniquely identifies the network on the Internet. ASNs are assigned by the Internet Assigned Numbers Authority (IANA).
path-vector
A _________________ protocol is similar in concept to a distance-vector protocol, but without the scalability issues associated with limited hop counts. Example: Border Gateway Protocol (BGP)
Border Gateway Protocol (BGP)
_______________ is a path-vector routing protocol used between separate autonomous systems (ASs). It's considered an Exterior Gateway Protocol (EGP) because it performs routing between separate autonomous systems. It's the core protocol used by Internet service providers (ISPs), network service providers (NSPs), and on very large private IP networks. When _________ runs between autonomous systems (such as between ISPs), it's called external _________ (e_________). When __________ runs within an AS (such as on a private IP network), it's called internal _________ (i__________). *Hint: same term/ acronym for all the blanks
Routed
______________ protocols are Network Layer protocols, such as Internetwork Packet Exchange (IPX) and Internet Protocol (IP) which address packets with routing information and allow those packets to be transported across networks using routing protocols.
Internetwork Packet Exchange (IPX)
_____________________________________ is a connectionless protocol used in primarily in older Novell NetWare networks for routing packets across the network. It's part of the IPX/ SPX (Internetwork Packet Exchange/ Sequenced Packet Exchange) protocol suite, which is analogous to the TCP/IP suite.
Internet Protocol (IP)
_________________________________ contains addressing information that enables packets to be routed. _________ is part of the TCP/IP (Transmission Control Protocol/ Internet Protocol) suite, which is the language of the Internet. _____ has two primary responsibilities: - Connectionless, best-effort (no guarantee of) delivery of datagrams. - Fragmentation and reassembly of datagrams.
IP Version 4 (IPv4)
_______________________________________, which is currently the most commonly used version, uses a 32-bit logical IP address that's divided into four 8-bit sections (octets) and consists of two main parts: - the network number - the host number
loopback
DUMMIES TECHNICAL: The address range 127.0.0.1 to 127.255.255.255 is a _______________________ network used for testing and troubleshooting. Packets sent to a 127 address are immediately routed to the source device. The most commonly used _______________ (or localhost) address for devices is 127.0.0.1 (sometimes called home), although any address in the 127 network range can be used for this purpose.
Technical note: Technically, we're not completely out of IPv4 addresses. Each regional Internet registry has reserved a very small pool of IPv4 addresses to facilitate the transition to IPv6.
DUMMIES TECHNICAL NOTE- Flip the card to read!!
IPv6 (Source: PCMag)
The latest generation of the IP protocol. IPv___ greatly increased the number of unique IP addresses that computers and devices connected to the Internet can be assigned. For all practical purposes, the quantity of addresses is unlimited. The IPv___ specification was completed in 1997 by the Internet Engineering Task Force (IETF) and first deployed in 2004 when ICANN added IPv____ records to its DNS root servers for Japan and Korea. IPv____ is backward compatible with IPv4 and was designed to fix its shortcomings, such as data security and maximum number of addresses. Virtually Unlimited Devices The address space was increased from 32 bits in IPv4 to 128 bits in IPv____ (see binary values). IPv____ also supports quality of service (QoS) parameters for real-time audio and video. Originally called "IP Next Generation" (IPng), IPv6 and IPv4 exist side-by-side. See NDP and SLAAC.
- Leading zeroes in an individual hextel can be omitted, but there must be at least one hexadecimal digit in each hextel, except as noted in the next rule. - Two colons (::) can be used to represent one or more groups of 16 bits of zeros, as well as leading or trailing zeroes in an address; the :: can only appear once in an IPv6 address. - In mixed IPv4 and IPv6 environments, the form x:x:x:x:x;x:d.d.d.d can be used, in which x represents the six high-order 16-bit hextels of the address and d represents the four low-order 8-bit octets (in standard IPv4 notation) of the address.
There are several rules the IETF has defined to shorten an IPv6 address: (?)
Letters in hexadecimal notation are not case-sensitive (A is the same as a, B is the same as b, and so on), so either form can be used in IPv6 addresses, although IETF recommends using lowercase letters.
Dummies Tip - Flip the Card!!
Although you don't need to know all intricate details of IPv6 addressing for the CISSP exam, as its use becomes more commonplace - particularly in IoT devices - you need to be familiar with the security enhancements in IPv6 and be able to recognize a valid IPv6.
Dummies Tip - Flip the Card!!
Multilayer protocols
__________________ protocols are groups of protocols that are purpose-built for some type of specialized communications need. ____________________ protocols have their own schemes for encapsulation, just like TCP/IP itself. One good example of this protocol is DNP3 (Distributed Network Protocol), which is used in industrial control systems (ICS) and supervisory control and data acquisition (SCADA) networks. DNP3 has a layer 2 framing layer, a layer 4 transport layer, and a layer 7 application layer. DNP3's original design lacks security features, such as authentication and encryption. Recent updates to the standard have introduced security protocols. Without security features, relatively simple attacks (such as eavesdropping, spoofing, and perhaps denial of service) can be easily carried out on specialized multiprotocol networks.
Converged protocols
___________________________ protocols refers to an implementation of two or more protocols for a specific communications purpose. Some examples of these protocols include: - MPLS (Multiprotocol Label Switching) - FCoE (Fibre Channel over Ethernet) - VoIP (Voice over Internet Protocol) - SIP (Session Initiation Protocol) - iSCSI (Internet Small Computer Systems Interface)
Software-defined networks (SDN)
_______________________________________, represent the ability to create, configure, manage, secure, and monitor network elements rapidly and efficiently. ______ utilizes an open standards architecture that enables intelligent network functions, such as routing, switching, and load balancing (the overlay function), to be performed on virtual software that is installed on commodity network hardware (the physical underlay), similar to server virtualization. In ________, network elements and network architectures are virtual; this enables organizations to quickly build and modify their networks and network elements. Like other virtualization technologies, _________ requires policy, process, and discipline to manage it correctly, in order to avoid network sprawl (the phenomenon where undisciplined administrators bypass change controls processes and unilaterally create virtual network elements). *Hint: same term/ acronym for all the blanks
- Internet Control Message Protocol (ICMP) - Simple Key Management for Internet Protocols (SKIP)
Other protocols defined at the Network Layer include the: (?)
Internet Control Message Protocol (ICMP)
_________________ is a Network Layer protocol that is used for network control and diagnostics. Commonly used __________ commands include ping and traceroute. Although __________ is very helpful in troubleshooting routing and connectivity issues in a network, it is also commonly used by attackers for network reconnaissance, device discovery, and denial-of-service (DoS) attacks (such as an ___________ flood). *Hint: same term/ acronym for all the blanks
Simple Key Management for Internet Protocols (SKIP)
_______________________ is a Network Layer key management protocol used to share encryption keys. An advantage of __________ is that it doesn't require a prior communication session to be established before it sends encrypted keys or packets. However, ____________ is bandwidth-intensive because of the size of additional header information in encrypted packets.
routers & gateways
The primary networking equipment defined at Layer 3 are ____________ and ___________________.
Routers
________________________ are intelligent devices that link dissimilar networks ad use logical or physical addresses to forward data packets only to the destination network (or along the network path). The devices employ various routing algorithms (for example, RIP, OSPF, and BGP) to determine the best path to a destination, based on different variables that include bandwidth, cost, delay, and distance.
Gateways
____________________________ are created with software running on a computer (workstation or server) or router. _____________________ link dissimilar programs and protocols by examining the entire Layer 7 data packet so as to translate incompatibilities. For example, a ________________ can be used to link an IP network to an IPX network or a Microsoft Exchange mail server to a Lotus Notes server (a mail _____________________).
Data Link Layer (Layer 2)
The ______________________ ensures that messages are delivered to the proper device across a physical network link. This layer also defines the networking protocol (for example, Ethernet, USB, and token ring) used to send and receive data between inidividual devices. The ___________________________ formats messages from layers above into frames for transmission, handles point-to-point synchronization and error control, and can perform link encryption.
Logical Link Control (LLC) & Media Access Control (MAC) sublayers
The IEEE 802 standards and protocols further divide the Data Link Layer into two sub-layers: the ________________________ and ______________________ sublayers.
The Data Link Layer is responsible for ensuring that messages are delivered to the proper device across a physical network link.
The Dummies book wants you to remember this! FLIP THE CARD!
- Provides an interface for the MAC sublayer by using Source Service Access Points (SSAPs) and Destination Service Access Points (DSAPs). - Manages the control, sequencing, and acknowledgement of frames being passed up to the Network Layer or down to the Physical Layer. - Bears responsibility for timing and flow control. Flow control monitors the flow of data between devices to ensure that a receiving device, which may not necessarily be operating at the same speed as the transmitting device, isn't overwhelmed and dropping packets.
The LLC sublayer operates between the Network Layer above and the MAC sublayer below. The LLC sublayer performs the following three functions:
The Logical Link Control (LLC) and Media Access Control (mac) are sublayers of the Data Link Layer.
The Dummies book wants you to remember this! FLIP THE CARD!
- Performs error control: Error control uses a cyclic redundancy check (CRC). A CRC is a simple mathematical calculation or checksum used to create a message profile. The CRC is recalculated by the receiving device. If the calculated CRC doesn't match the received CRC, the packet is dropped and a request to re-send is transmitted back to the device that sent it. - Identifies hardware device (or MAC) addresses: A MAC address (also known as a hardware address or physical address) is a 48-bit address that's encoded on each device by its manufacturer. The first 24 bits identify the manufacturer or vendor. The second 24 bits uniquely identify the device. - Controls media access: The three basic types of media access are- Contention; Token-passing; Polling
The MAC sublayer operates between the LLC sublayer above the Physical Layer below. It's primarily responsible for framing and has the following three functions: (?)
Contention
In _____________________-based networks such as Ethernet, individual devices must vie for control of the physical network medium. This type of network is ideally suited for networks characterized by small bursts of traffic. Ethernet networks use a ____________________-based method, known as Carrier Sense Multiple Access with Collision Detection (CSMA/CD), in which all stations listen for traffic on the physical network medium. If the line is clear, any station can transmit data. However, fi another station attempts to transmit data at the same time, a collision occurs, the traffic is dropped, and both stations must wait a random period of time before attempting to re-transmit. Another method, used in Apple LocalTalk and Wi-Fi networks, is known as Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA).
Token-passing
In ________________________ networks such as token ring and Fiber Distributed Data Interface (FDDI), individual devices must wait for a special frame, known as a token, before they transmit data across the physical network medium. This type of network is considered deterministic (transmission delay can be reliably calculated, and collisions don't occur) and is ideally suited for networks that have large, bandwidth-consuming applications that are delay-sensitive. ______________, FDDI, and ARCnet networks all use various token passing methods for media access control.
Polling
In __________________ networks, individual devices (secondary hots) are polled by a primary host to see whether they have data to be transmitted. Secondary hosts can't transmit until permission is granted by the primary host. _____________________ is typically used in mainframe environments and wireless networks.
- Ethernet - ARCnet - Token Ring - Fiber Distributed Data Interface (FDDI) - Address Resolution Protocol (ARP) - Reverse Address Resolution Protocol (RARP)
Common LAN protocols are defined at the Data Link (and Physical) Layer. They include the following: (?)
Ethernet
The _________________________ protocol transports data to the physical LAN medium by using CSMA/CD (discussed in preceding section). It is designed for networks characterized by sporadic, sometimes heavy traffic requirements. ______________________ is by far the most common LAN protocol used today- most often implemented with twisted-pair cabling (discussed in the section "Cable and connector types"). _____________ operates at speeds up to 10 Mbps, Fast _________________ operates at speeds to 100 Mbps (over Cat 5 twisted-pair or fiber-optic cabling), and Gigabit _________________ operates at speeds up to 40 Gbps (over Cat 5e, Cat 6, or Cat 7 twisted-pair or fiber-optic cabling). *Hint: same term/ acronym for all the blanks
ARCnet
The ___________________ protocol is one of the earliest LAN technologies developed. It transports data to the physical LAN medium by using the token passing media access method that we discuss in the preceding section. It's implemented in a star topology by using coaxial cable. _____________________ provides slow-but-predictable network performance. *Hint: same term/ acronym for all the blanks
Token Ring
The _________________________________ protocol transports data to the physical LAN medium by using the token passing media access method that we discuss in the preceding section. In a ________________________ network, all nodes are attached to a Multistation Access Unit (MAU) in a logical ring (but physical star) topology. One node of the token ring network is designated as the active monitor and ensures that no more than one token is on the network at any given time. (Variations permit more than one token on the network.) If the token is lost, the active monitor is responsible for ensuring that a replacement token is generated. ___________________ networks operate at speeds of 4 and 16 Mbps- pretty slow by today's standards. ______________________ networks are not often seen nowadays. *Hint: same term/ acronym for all the blanks
Fiber Distributed Data Interface (FDDI)
The ______________ protocol transports data to the physical LAN medium by using the token passing media access method that we discuss in the preceding section. It's implemented as a dual counter-rotating ring over fiber-optic cabling at speeds up to 100 Mbps. All stations on a FDDI network are connected to both rings. During normal operation, only one ring is active. In the event of a network break or fault, the ring wraps back through the nearest node on the second ring. *Hint: same term/ acronym for all the blanks
Address Resolution Protocol (ARP)
_____________ maps Network Layer IP addresses to MAC addresses. _____________ discovers physical addresses of attached devices by broadcasting ___________ query messages on the network segment. IP-address-to-MAC-address translations are then maintained in a dynamic table that's cached on the system. *Hint: same term/ acronym for all the blanks
Reverse Address Resolution Protocol (RARP)
_____________ maps MAC addresses to IP addresses. This process is necessary when a system, such as a diskless machine, needs to discover its IP address. The system broadcasts a __________ message that provides the system's MAC address and requests to be informed of its IP address. A __________ server replies with the requested information. *Hint: same term/ acronym for all the blanks
Both ARP and RARP and Layer 2 protocols. ARP maps an IP address to a MAC address and is used to identify a device's hardware address when only the IP address is known. RARP maps a MAC address to an IP address and is used to identify a device's IP address when only the MAC address is known.
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- Unicast: Packets are sent from the source to a single destination device by using a specific destination IP address. - Multicast: Packets are copied and sent from the source to multiple destination devices by using a special multicast IP address that the destination have been specifically configured to use. - Broadcast: Packets are copied and sent from the source to every device on a destination network by using a broadcast IP address.
LAN data transmissions are classified as: (?)
LAN data transmission are classified as unicast, multicast, or broadcast.
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WLAN (wireless LAN)
_______________________________ technologies, commonly known as Wi-Fi, function at the lower layers of the OSI Reference Model. WLAN protocols define how frames are transmitted over the air.
Speed: 54 Mbps Description: Operates at 5GHz (less interference than at 2.4 GHz)
Wireless LAN Standards: 802.11a- what is the speed? describe it?
Speed: 11 Mbps Description: Operates at 2.4 GHz (first widely used protocol)
Wireless LAN Standards: 802.11b- what is the speed? describe it?
Speed: 54 Mbps Description: Operates at 2.4 GHz (backward-compatible with 802.11b)
Wireless LAN Standards: 802.11g- what is the speed? describe it?
Speed: 600 Mbps Description: Operates at 5 GHz or 2.4 GHz
Wireless LAN Standards: 802.11n- what is the speed? describe it?
Speed: 1 Gbps Description: Operates at 5 GHz
Wireless LAN Standards: 802.11ac- what is the speed? describe it?
TRUE
TRUE/ FALSE: WLAN networks were first encrypted with the WEP (Wired Equivalent Privacy) protocol, which was soon proven to be insufficient. New standards of encryption include WPA (Wi-Fi protected access) and WPA2. WPA using TKIP (Temporal Key Integrity Protocol) is also considered insufficient; AES (Advanced Encryption Standard) should be used instead.
- Point to Point links (links include: L2F, L2TP, PPP, PPTP, & SLIP) - Circuit-switched networks (examples: xDSL, DOCSIS, & ISDN) - Packet-switched networks (includes: ATM, Frame Relay, MPLS, SDH, SMDS, & X.25) - Other WAN protocols (HDLC & SDLC)
WAN technologies functions at the lower three layers of the OSI Reference Model (the Physical, Data Link, and Network Layers), primarily at the Data Link Layer. WAN protocols define how frames are carried across a single data link between two devices. These protocols include: (?)
point-to-point links
These links provide a single, pre-established WAN communications path from the customer's network, across a carrier network (such as Public Switched Telephone Network [PSTN]), to a remote network. These ________________ links include: - Layer 2 Forwarding Protocol (L2F) - Layer 2 Tunneling Protocol (L2TP) - Point-to-Point (PPP) - Point-to-Point Tunneling Protocol (PPTP) - Serial Line IP (SLIP)
Layer 2 Forwarding Protocol (L2F)
A tunneling (data encapsulation) protocol developed by Cisco and used to implement VPNs, specifically Point-to-Point Protocol (PPP) traffic. ___________ provides encapsulation but doesn't provide encryption or confidentiality.
Layer 2 Tunneling Protocol (L2TP)
A tunneling protocol used to implement VPNs. _____________ is derived from L2F (described in the preceding item) and PPTP and uses UDP port 1701 to create a tunneling session. _____________ is commonly implemented along with an encryption protocol, such as IPsec, because it doesn't encrypt traffic or provide confidentiality by itself.
Point-to-Point (PPP)
The successor to SLIP, ________ provides router-to-router and host-to-network connections over synchronous and asynchronous circuits. It's a more robust protocol than SLIP and provides additional built-in security mechanisms. ________________ is far more common than SLIP in modern networking environments.
Point-to-Point Tunneling Protocol (PPTP)
A tunneling protocol developed by Microsoft and commonly used to implement VPNs, specifically PPP traffic. _____________ doesn't provide encryption or confidentiality, instead relying on other protocols, such as PAP, CHAP, and EAP, for security.
Serial Line IP (SLIP)
The predecessor of Point-to-Point Protocol (PPP), ___________ was originally developed to support TCP/IP networking over low-speed asynchronous serial lines (such as dial-up modems) for Berkeley UNIX computers. _____________ is rarely seen today, except in computer museums.
Circuit-switched networks
In a _______________________, a dedicated physical circuit path is established, maintained, and terminated between the sender and receiver across a carrier network for each communications session (the call). This network type is used extensively in telephone company networks and functions similarly to a regular telephone call. Examples include: Digital Subscriber Line (xDSL), Data Over Cable Service Interface Specification (DOCSIS) and Integrated Services Digital Network (ISDN).
Digital Subscriber Line (DSL)
________ uses existing analog phone lines to deliver high-bandwidth connectivity to remote customer.
Data Over Cable Service Interface Specification (DOCSIS)
__________________ is a communications protocol for transmitting high speed data over an existing cable TV system.
Integrated Services Digital Network (ISDN)
___________________ is a communications protocol that operates over analog phone lines that have been converted to use digital signaling. __________ lines are capable of transmitting both voice and data traffic. ___________ defines a B-channel for data, voice, and other services, and a D-channel for control and signaling information. With the introduction and widespread adoption of DSL and DOCSIS, ISDN has largely fallen out of favor in the United States and is no longer available in many areas. *Hint: same term/ acronym for all the blanks
Circuit-switched networks are ideally suited for always-on connections that experience constant traffic.
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Packet-switched networks
In a ___________________________ network, devices share bandwidth (by using statistical multiplexing) on communications links to transport packets between a sender and receiver across a carrier network. This type of network is more resilient to error and congestion than circuit-switched networks. Example: Asynchronous Transfer Mode (ATM), Frame Relay, Multi-Protocol Label Switching (MPLS), Synchronous Optical Network (SONET) and Synchronous Digital Hierarchy (SDH), Switched Multimegabit Data Service (SMDS), & X.25.
Asynchronous Transfer Mode (ATM)
A very high-speed, low-delay technology that uses switching and multiplexing techniques to rapidly relay fixed-length (53-byte) cells that contain voice, video, or data. Cell processing occurs in hardware that reduces transit delays. _________ is ideally suited for fiber-optic networks that carry bursty (uneven) traffic.
Frame Relay
A packet-switched, standard protocol that handles multiple virtual circuits by using High-level Data Link Control (HDLC) encapsulation between connected devices. ____________________ utilizes a simplified framing approach that has no error correction and Data Link Connection Identifiers (DLCIs) to achieve high speeds across the WAN. _____________________ can be used on Switched Virtual Circuits (SVCs) or Permanent Virtual Circuits (PVCs). An SVC is a temporary connection that's dynamically created (in the circuit establishment phase) to transmit data (which happens during the data transfer phase) and then disconnected (in the circuit termination phase). PVCs are permanently established connections. Because the connection is permanent, a PVC doesn't require the bandwidth overhead associated with circuit establishment and termination. However, PVCs are generally a more expensive option than SVCs.
Multi-Protocol Label Switching (MPLS)
A packet-switched, high-speed, highly scalable and highly versatile technology used to create fully meshed Virtual Private Networks (VPNs). It can carry IP packets, as well as ATM, SONET (Synchronous Optical Networking), or Ethernet frames. _________ is specified at both Layer 2 and Layer 3. Label Edge Routers (LERs) in an _________ network push or encappsulate a packet (or frame) with an ________ label. The lable information is used to switch the payload through the ___________ cloud at very high speeds. Label Switch Routers (LSRs) witin the __________ cloud make routing decisions based solely on the label information, wihtout actually examining the payload. At the egress point, an LER pops (decapsulates) the packet, removing the ___________ label when the packet exits the __________ network. One disadvantage of an _________ network is that a customer loses visibility into the Cloud. Or, if you're a glass-is-half-full type, one advantage of an ________ network is that an attacker loses visibility into the Cloud. *Hint: same term/acronym for all the blanks
Synchronous Optical Network (SONET) and Synchronous Digital Hierarchy (SDH)
A high-availability, high-speed, multiplexed, low-latency technology used on fiber-optic networks. ______________ was originally designed for the public telephone network and is widely used throughout the U.S. and Canada, particularly within the energy industry. Synchronous Digital Hierarchy (SDH) was developed after _________ and is used throughout the rest of the world. Data rates for ______________ and SDH are defined at OC (optical carrier) levels *Hint: only used one term and it's the same throughout all of the blanks
Switched Multimegabit Data Service (SMDS)
A high-speed, packet-switched, connectionless-oriented, datagram-based technology available over public switched networks. Typically, companies that exchange large amounts of data bursts with other remote networks use ______________.
X.25
The first packet-switching network, _______ is an International Telecommunication Union - Telecommunicatioons (ITU-T) standard that defines how point-to-point connections between data terminal equipment (DTE) and data carrier equipment (DCE) are established and maintained. ________ specifies the Link Access Procedure, Balanced (LAPB) protocol at the Data Link Layer and the Packet Level Protocol (PLP; also known as _________ Level 3) at the Network Layer. ________ is more common outside the United States but largely has been superseded by MPLS and Frame Relay.
Packet-switched networks are ideally suited for on-demand connections that have bursty traffic
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High-level Data Link Control (HDLC)
A bit-oriented, synchronous protocol that was created by the ISO to support point-to-point and multipoint configurations. Derived from SDLC, it specifies a data encapsulation method for synchronous serial links and is the default for serial links on Cisco routers. Unfortunately, various vendor implementations of the _________________________ protocol are incompatible.
Synchronous Data Link Control (SDLC)
A bit-oriented, full-duplex serial protocol that was developed by IBM to facilitate communications between mainframes and remote offices. It defines and implements a polling method of media access, in which the primary (front end) pols the secondaries (remote stations) to determine whether communication is required.
- bridges - switches - DTEs/ DCEs - wireless equipment
Networking devices that operate at the Data Link Layer include: (?)
bridge
A _____________________ is a semi-intelligent repeater used to connect two or more (similar or dissimilar) network segments. A ____________ maintains an Address Resolution Protocol (ARP) cache that contains the MAC addresses of individual devices on connected network segments. When a ______________ receives a data signal, it checks its ARP cache to determine whether the destination MAC address is on the local network segment. If the data signal turns out to be local, it isn't forwarded to a different network; if the MAC address isn't local, however, the _____________ forwards (and amplifies) the data signal to all other connected network segments. A serious networking problem associated with ________ is a broadcast storm, in which broadcast traffic is automatically forwarded by a __________, effectively flooding a network. Network ___________ have been superseded by switches. *Hint: same term for all the blanks
Asynchronous
_______________________________ communication transmits data in a serial steam that has control data (start and stop bits) embedded in the stream to indicate the beginning and end of characters. __________________________ devices must communicate at the same speed, which is controlled by the slower of the two communicating devices. Because no internal clocking signal is used, parity bits are used to reduce transmission errors. *Hint: same term for all the blanks
Synchronous
____________________________________ communications utilize an internal clocking signal to transmit large blocks of data, known as frames. ____________________________ communication is characterized by very high-speed transmission rates. *Hint: same term for all the blanks
Data Terminal Equipment (DTE)
__________________________________ is a general term used to classify devices at the user end of a user-to-network interface (such as computer workstations). A __________ connects to Data Carrier Equipment (DCE; also known as Data Circuit-Terminating Equipment), which consists of devices at the network end of a user-to-network interface. The _______ provides the physical connection to the network, forwards network traffic, and provides a clocking signal to synchronize transmissions between the DCE and the ______. Examples: NICs (Network Interface Cards), modems, and CSUs/DSUs (Channel Service Units).
Wireless Access Points (APs) (Source: Techopedia)
A ____________________________________ is a hardware device or configured node on a local area network (LAN) that allows wireless capable devices and wired networks to connect through a wireless standard, including Wi-Fi or Bluetooth. _____________________________ feature radio transmitters and antennae, which facilitate connectivity between devices and the Internet or a network. Also known as a hotspot. _____________________________may be used to provide network connectivity in office environments, allowing employees to work anywhere in the office and remain connected to a network. In addition, __________________ provide wireless Internet in public places, like coffee shops, airports and train stations. _______________________________ are most commonly thought of in the context of the 802 series of wireless standards, commonly known as Wi-Fi. While there are other wireless standards, the vast majority of the time the terms Wi-Fi hotspot and _____________________ are synonymous. *Hint: same term/ acronym for all blanks
- omnidirectional - parabolic - sectorized - yagi
What are the 4 basic types of wireless antennas?
omnidirectional
The most common type of wireless antenna,__________________________________ are essentially short poles that transmit and receive wireless signals with equal strength in all directions around a horizontal axis. These type of antennas are often a dipole design.
parabolic
Also known as dish antennas, ___________________ are directional dish antennas made of meshed wire grid or solid metal. These type of antennas are used to extend wireless ranges over great distances.
sectorized
Similar in shape to omni-directional antennas, _________________________________ have reflectors that direct transmitted signals in a specific direction (usually a 60-120 degree pattern) to provide additional range and decrease interference in a specific direction.
yagi
Similar in appearance to a small aerial TV antenna, ___________________________________ are used for long distances in point-to-point or point-to-multipoint wireless applications.
- root mode - repeater mode - bridge mode - mesh mode
Access points (APs) can operate in one of 4 modes:
root mode
The default configuration for most APs. The AP is directly connected to the wired network, and wireless clients access the wired network via the wireless access point. Also known as infrastructure mode.
repeater mode
The AP doesn't connect directly to the wired network, but instead provides an upstream link to another AP, effectively extending the range of the WLAN. Also known as stand-alone mode.
bridge mode
A rare configuration that isn't supported in most APs. ____________ mode is used to connect two separate wired network segments via a wireless access point.
mesh mode
Multiple APs work together to create the appearance of a single Wi-Fi network for larger homes and workspaces.
Ad hoc
Dummies Tip: _____________________ is a type of WLAN architecture that doesn't have any APs. The wireless devices communicate directly with each other in a peer-to-peer network, such as between two notebook computers.
Physical Layer (Layer 1)
The ______________________________________ sends and receives bits across the network medium (cabling or wireless links) from one device to another. It specifies the electrical, mechanical, and functional requirements of the network, including network topology, cabling and connectors, and interface types, as well as the process for converting bits to electrical (or light) signals that can be transmitted across the physical medium. Various network topologies, made from copper or fiber-optic wires and cables, hubs, and other physical materials, comprise the _______________ layer. *Hint: same term for both blanks
- star - mesh - ring - bus
There are 4 basic network topologies defined at the Physical Layer. List them: (?)
star
Each individual node on the network is directly connected to a switch, hub, or concentrator. All data communications must pass through the switch (or hub), which can become a bottleneck or single point of failure. A ____________ topology is ideal for practically any size environment and is the most common basic topology in use today. A _______________ topology is also easy to install and maintain, and network faults are easily isolated without affecting the rest of the network. *Hint: same term for all the blanks
mesh
All systems are interconnected to provide multiple paths to all other resources. In most networks, a partial ___________ is implemented for only the most critical network components, such as routers, switches, and servers (by using multiple network interface cards [NICs] or server clustering) to eliminate single points of failure.
ring
A closed loop that connects end devices in a continuous __________. Functionally, this is achieved by connecting individual devices to a Multistation Access Unit (MSAU or MAU). Physically, this setup gives the ______________ topology the appearance of a star topology. __________ topologies are common in token ring and FDDI networks. In a ________ topology, all communication travels in a single direction around the ________. *Hint: same term for all the blanks
bus
in a ____________________ topology, all devices are connected to a single cable (the backbone) that's terminated on both ends. ___________ networks were commonly used for very small networks because they're inexpensive and easy to install. However, in large environments, they're impractical because the media has physical limitations (namely, the length of the cabling), the backbone is a single point of failure (a break anywhere on the network affects the entire network), and tracing a fault in a large network can be extremely difficult. _______ networks are extremely rare today and are no longer the least-expensive or easiest-to-install network option. *Hint: same term for all the blanks
baseband
A communication medium that supports only a single communication signal at a time.
broadband
A communication medium that supports multiple communication signals simultaneously.
coaxial cable or coax
A cable with a center core of copper wire surrounded by a layer of insulation and then by a conductive braided shielding and finally encased in an insulation sheath. _____________________ is fairly resistant to EMI, has a low cost, and is easy to install.
- thick - thin
Coax cable comes in two flavors: (?)
thick Also known as RG8 or RG11 or thicknet
_____________ cable uses a screw-type connector, known as an Attachment Unit Interface (AUI)
thin
_____________ cable is typically connected to network devices using a bayonet-type connector, known as a BNC (Bayonet Neill-Concelman) connector.
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