Address Resolution Protocol

• ARP knows the IP address of a device and broadcasts messages to find the matching MAC address.
• Stores IP and MAC mappings in an ARP table.
• helps data link layer protocols to find the MAC addresses for the known IP address
• RARP does the exact opposite and looks for an IP address of a known MAC address.

• Telnet port 23
• SMTP port 25
• HTTP port 80
• SNMP ports 161 and 162
• FTP ports 20 and 21
• TFTP port 69
• HTTPS port 443

• combine data link layer, network layer and other layer functionality
• offer routing functionality, packet inspection, traffic prioritization, and quality of service (QoS) functionality.
• way more functionality than layer 2 switches

Multistation Access Unit

• acts as a central hub in a token ring network
• each computer in a token ring network is connected to the MAU

Synchronous Data Link Control

• enables secondary devices to communicate with the primary stations or mainframes in an IBM architecture.
• Original IBM proprietary protocol

• filters external traffic and passes it on to firewall and then onto the internal network
• created a DMZ by using two routers or firewalls.

• provides encryption when combined with L2TP
• transport mode refers to protecting just the payload
• tunnel mode protects the headers and the data payload
• helps to provide VPNs that boast strong encryption and authentication functionality
• Operates at the Network layer

Fiber Distributed Data Interface

• high speed token passing technology
• transmission speeds of 100Mbps
• Used primarily as a MAN technology (connects different networks together) but can be used as LAN
• uses fiber optic rings to connect different networks. Contains redundant rings in case the primary ring goes down.

• look within the fram to gain more than just routing and address information
• translation may need to be performed when two different environments are trying to communicate (i.e. novell and microsoft)
• Usually operates at the application layer

Internet Group Management Protocol

• used to report multicast group memberships to routers.

• work at physical layer
• help amplify a signal so that it can pass on to the next segment
• helps extend the network

• divides networks into more controllable segments to ensure more efficient use of bandwidth.
• works at the data link layer
• uses physical or MAC addresses when making decisions on where to send traffic (not IPs)
• can perform simple forwarding or more complex filtering
• each function is based on MAC which resides on the data link layer

• can carry up to 28 T1 lines
• can provide 45 Mbps of bandwidth

• used to connect multiple switches for traffic of the same class

Data Link Layer

Sublayers

• Logical Link Control (LLC) communicates with protocols above it in the network layer. (defined in IEEE 802.2 specification)
• Media Access Control (MAC) communicates with protocols below it in the physical layer. (defined in the IEEE MAC specification for ethernet is 802.3; token ring 802.5; wireless 802.11, 802.16; etc.)

Synchronous Optical Network

• standard for fiber-optic cabling
• works at physical layer
• uses self-healing network rings
• majority of MANs today are SONETs

High-Level Data Link Control

• based upon SDLC protocol
• both are bit oriented and work over asynchronous lines
• Unlike SDLC, HDLC supports full-duplex connections, thus providing higher throughput

• provides fixed bandwidth that can be allocated for specific applications (unlike FDDI)
• works more like a broadband connection allowing voice, video, and data to travel on the same lines.

Asynchronus Tranfer Mode

• transfers data in fixed cells, is a WAN technology, and transmits data at very high rates. It supports voice, data, and video applications.
• used in LAN and WAN implementations
• Data are segmented into fixed-size cells of 53 bytes, instead of variable-size packets.
• fixed size provides better performance and a reduced overhead for error handling.

Layer 2 Tunneling Protocol

• can tunnel through networks that incorporate many types of protocols (X.25, ATM, Frame Relay)
• Does not provide encryption
• Must be paired with IPsec for encryption

• WAN protocol that operates at the data link layer
• Uses packet switching technology to let multiple companies and networks share the same WAN media
• Cost is based on amount of bandwidth used
• Can pay more to ensure higher level of bandwidth (CIR - committed information rate)
• Two types of equipment used (DTE or DCE)

Sequenced Packet Exchange

• Resides on the Host-to-Host layer which is equivalent to Transport layer in OSI model
• Pairs with IPX which is on the Network layer of OSI model. 
• SPX/IPX is to TCP/IP when it comes to OSI levels

Wireless Application Protocol

• "Gap in the Wap" is brief moment of translation at the gateway
• Set of communication protocols used to standardize the way wireless devices interface with each other and the internet
• Uses WML instead of XML and WTLS instead of TLS&SSL
• Gateway is required to translate between WAP and internets protocols and app types.

• deals with much smaller network, referred to as wireless personal are network (WPAN)
• allows for connectivity to take place among local devices like a computer and a PDA or cellphone
• Bluetooth is a portion of 802.15 standard

• (MAN) Metropolitan Area Network wireless standard. Also referred to as broadband wireless access.

• uses MIMO concept (p.639)
• attempt to replace current mix of WiFi tecnhologies
• throughput up to 100Mbps
• works at 56Hz range (much less busy)
• Intent is to maintain backwords compatability with current standards while combining mix of current technologies.

• 802.11j task group has been working on bringing together many different standards and steamlining their development to allow for better interoperability across country borders.

Extensible Authentication Protocol

• use of EAP allows different authenticater protocols to be used by different vendors
• works with 802.1X to enforce mutual authentication between wireless device adn authentication server.

• uses EAP which allows for mutual authentication between device adn authorization server
• wide range of security flaws in 802.11
• employs two different approaches that provide much moe security.
• TKIP - backwards compatible wit hmany currently implemented networks
• CCMP - uses AES in counter mode with CBC-MAC. Not backwards compatible
• lower layer contains CCMP and TKIP while layer on top contains 802.1x

• a standard tah tis a port-based network access control that ensures a user can not make a full network connection until properly authenticated.
• allows for user authentication while WEP provides system authentication
• provides framework for EAP modules

Wired Equivalent Privacy

• used RC4 encryption
• Deficiencies include static encryption keys, ineffective use of initialization vectors, and lack of packet integrity assurance.
• used wit hstandard 802.11
• all three deficiencies are addressed with the use of TKIP

Temporal Key Integrity Protocol

• addresses the dificiencies of WEP pertaining to static WEP keys and inadequate use of IV values
• provides ability to rotate encryption keys

• Builds upon 802.11a specifications to meet requirements of European wireless rules
• 802.11h can be implemented in European countries because of this

• Provides for up to 54Mbps
• Basically a speed extension for 802.11b products
• Since 802.11b works only up to 11 Mbps
• A new 802.11g based product can be backward compatible but work at higher transfer rate.
• works in 2.4 Ghz range.

• Higher frequency equals shorter range
• uses OFDM modulation scheme
• works in teh 5 Ghz frequency band 
• not backwards compatible w 802.11b or 802.11
• provides up to 54 Mbps
• maximum speed is attained at short distances from AP (up to 25 feet)
• mostly used in US
• OFDM splits signal over several channels (spectrum) which helps with interference

• most commonly used today
• works in 2.4 Ghz range
• provides transfer rate of up to 11 Mbps
• uses DSSS modulation scheme
• backwards compatible with 802.11 implementations

• deals with the conveying of information between teh different APs during roaming
• roaming is when a user moves out of range of one AP and another AP needs to pick up and maintain the users signal so the user does not lose connectivity.

• provided QoS and proper support of multimedia traffic
• QoS provides capability to prioritize traffic, and affords guaranteed delivery
• Multimedia apps have a lower tolerance for delays in data transmission

• TCP - Transmission Control Protocol
• UDP - User Datagram Protocol
• SSL - Secure Sockets Layer
• TLS - Transport Layer Security
• SPX - Sequenced packer Exchange

• IP - Internet Protocol
• ICMP - Internet Control Message Protocol
• IGMP - Internet Group Management Protocol
• RIP - Routing Information Protocol
• OSPF - Open Shortest Path First
• IPX - Novel Internetwork Packet Exchange

• HSSI - High Speed Serial Interface
• X.21
• EIA/TIA-232
• EIA/TIA-449

• ASCII - American Standard Code for Information Interchange
• EBCDIC - Extended Binary Coded Decimal Interchange Mode
• TIFF - Tagged image File Format
• JPEG - Joint Photographic Experts Group
• MPEG - Motion Picture Experts Group
• MIDI - Musical Instrument Digital Interface

• NFS - Network File System
• NetBIOS
• SQL - Structured Query Language
• RPC - Remote Procedure Call

• Application (equal to App, Presentation, and Session in OSI Model)
• Host to Host (Transport in OSI Model)
• Internet (Network Layer in OSI Model)
• Network Access (Data Link, Physical Layers in OSI Model)

• FTP - File Transfer Protocol
• TFTP - Trivial File Transfer Protocol 
• SNMP - Simple Network Management Protocol
• SMTP - Simple Mail Transfer Protocol
• Telnet
• HTTP - Hypertext Transfer Protocol
• LPD - Line Printer Daeman

• Appliation
• Presentation
• Session
• Transport
• Network
• Data Link
• Physical
• Please Do Not Tell Secret Passwords Anytime

• ARP - Address Resolution Protocol
• RARP - Reverse Address Resolution Protocol
• PPP - Point to Point Protocol
• SLIP - Serial Line Internet Protocol
• L2F - Layer 2 Forwarding
• L2TP - Layer 2 Tunneling Protocol
• FDDI
• ISDN - Integrated Services Digital Network

• 1 = ICMP
• 6 = TCP
• 17 = UDP
• 2 = IGMP