Exam 1 Cheat sheet PDF

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This is a cheatsheet for the Exam I...

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Multicast: A network communication in which a packet is addressed so that more than one destination can receive it. ! Supernetting - combining smaller subnets into a larger supernet. ! IEEE! PDU at each layer! CIDR Notation

Class: ! A: 0-127 B: 128-191 C: 192-223! D: 224-239 E: 240-255! IPv4 - 32bit divided into 4 octets! IPv6 - 128bits host and net each 64 bits! How to get Network ID vs Host ID and why! 2^(n-1)! Subnet Mask: also 32 bits, each binary 1 in the subnet mask means the equivalent bits in the IP are network id. Do anding.! Reserved Private Addresses:! A addresses beginning with 10" B addresses from 172.16 to 172.31" C addresses from 192.168.0 to 192.168.255 " CIDR - A.B.C.D/n; n is the number of 1 bits in the subnet mask or the number of bits in the network ID. ! Loopback Address: always refers to the local computer; IPv4 127.0.0.1 IPv6 it’s ::1. used to test TCP/IP functionality locally! Subnets: subdivision of IP net address space. Subnetting: reallocates bits from an IP address’s host portion to the network portion, creating multiple smaller address spaces. Teredo: automatic IPv6-overIPv4 tunneling protocol.! Tunneling: A common network protocol technique that allows transmitting a packet in a format that would otherwise be incompatible for the network architecture by encapsulating the packet in a compatible header format.

6to4: transition protocol that provides automatic tunneling of IPv6 traffic over an IPv4 network! Address Space: The number of addresses available in an IP network number that can be assigned to hosts.! Anycast Address: Address type in IPv6 to allow a one-to-many relationship, and a packet is delivered to only one of the many possible destination computers.! Automatic Private IP Addressing (APIPA): when an IP address is requested via DHCP but no DHCP server responds to the request a APIPA enabled computer uses this private IP.! Broadcast Domain: The bounds of a network that defines which devices must receive a packet that’s broadcast by any other device; usually an IP subnet.! Classful Addressing: default subnet masks according to their address class: A, B, or C. A = 255.0.0.0 B = 255.255.0.0 C = 255.255.255.0! Classless Interdomain Routing (CIDR): network and host IDs are determined by a prefix number that specifies how many bits of the IP address are network bits. Dotted Decimal Notation: IPv4 notation! Dual IP Layer Architecture: The current architecture of the IPv6 protocol in Windows, in which both IPv4 and IPv6 share the other components of the stack. ! Extended Unique Identifier (EUI)-64 Interface ID: An auto-configured IPv6 host address that uses the MAC address of the host plus an additional 16 bits. ! Intra-Site Automatic Tunnel Addressing Protocol (ISATAP): An automatic tunneling protocol used to transmit IPv6 packets between dual IP layer hosts across an IPv4 network. See also dual IP layer architecture. ! IP Prefix: A value used to express network ID bits! Link-Local Address:IP that can only be used to comm on the local subnet.! Link-Local IPv6 Address: begin with fe80, self-configuring, and can’t be routed.! Local Host: reserved name that corresponds to the loopback address! Metric: value assigned to the gateway based on the speed of the interface used to access the gateway. Multicast Address: An address that identifies a group of computers running a multicast application. ! Multicasting: net comm where a packet is addressed so that more than one destination can receive it. ! Multihomed Server: A server with two or more NICs, each attached to a different IP network.! NAT: A service that translates a private IP address to a public IP address in packets destined for the Internet, and then translates the public IP address in the reply to the private address. For each private ip need 1 public ip.! Octet: 8-bit value from 0-255 Port Address Translation: Extension of NAT that allows hundreds of comps to use 1 public ip by using transport layer port numbers to differ comps.

Unicast Address: An address in a unit of network data intended for a single destination device. ! Unique Local IPv6 Address: private addresses can't be routed! Access Control: In the context of the Network layer and routing, the process by which a router consults a list of rules before forwarding an incoming packet. The rules determine whether a packet meeting certain criteria (such as source and destination address) should be permitted to reach the intended destination.! Deencapsulation: The process of stripping the header from a PDU as it makes its way up the communication layers before being passed to the next higher layer. See also protocol data unit (PDU). ! Encoding: Representing 0s and 1s as a physical signal, such as electrical voltage or a light pulse. ! International Organization for Standardization (ISO):The international standards-setting body based in Geneva, Switzerland, that sets worldwide technology standards. ! Logical Link Control (LLC) Sublayer: The upper sublayer of the IEEE Project 802 model for the OSI model’s Data Link layer. It handles error-free delivery and controls the flow of frames between sender and receiver across a network. ! Maximum Transmission Unit (MTU): The maximum frame size allowed to be transmitted across a network medium. ! Media Access Control (MAC) Sublayer: The lower sublayer of the IEEE Project 802 model for the OSI model’s Data Link layer. It handles accessing network media and mapping between logical and physical network addresses for NICs. ! Network Layer: Layer 3 of the OSI model handles logical addressing and routing of PDUs across inter-networks. See also Open Systems Interconnection (OSI) reference model and protocol data unit (PDU). ! Open Systems Interconnection (OSI) Reference Model: ISO Standard 7498 defines a frame of reference for understanding networks by dividing the process of network communication into seven layers. Each layer is defined in terms of the services and data it handles on behalf of the layer above it and the services and data it needs from the layer below it. ! Peer Communication: In the layered approach, each layer on one computer behaves as though it were communicating with its counterpart on the other computer. This means each layer on the receiving computer sees network data in the same format its counterpart on the sending computer did. ! Protocol Data Unit (PDU): A unit of information passed as a self-contained data structure from one layer to another on its way up or down the network protocol stack. ! !...