CCNA 1: Ch. 5 Vocab

  1. route
    Path through an internetwork through which packets are forwarded.
  2. source IP address
    The IP address of the originating-host that is placed into the IP packet header.
  3. IP header
    Header defined by the IP.

    Used to create IP packets by encapsulating data from higher layer protocols with an IP header.
  4. routing

    1. router receives frame

    2. discards data-link header & trailer

    3. makes forwarding decision based on destination IP add.

    4. adds new data-link header & trailer based on outgoing interface

    5. forwards frame out the appropriate interface.
  5. hop
    The passage of a data packet between two network nodes (for example, between two routers).
  6. directly connected network
    A network that is connected to a device's interface.

    For example, networks that interface with the router are known to be directly connected.

    Devices learn their initial IP routes based on being connected to these subnets.
  7. connection oriented
    Communication where the sender and receiver must prearrange for communications to occurs; otherwise, the communication fails.
  8. connectionless
    Any communication in which the sender and receiver do not prearrange for communications to occur.
  9. Destination IP address
    Layer 3 address to which the data is going.
  10. overhead
    Resources used to manage or operate the network.

    • Consumes bandwidth
    • Reduces the amount of data that can be transported across the network.
  11. best-effort
    Network protocols or technologies that do not use the acknowledgment system to guarantee reliable delivery of information.
  12. media independent
    Networking layers that are not affected by the media being used.

    In Ethernet these are all of the layers from the LLC sublayer of the Data Link layer and above.
  13. MTU
    Maximum Transmission Unit

    Largest IP packet size allowed to be sent out a particular interface.

    Ethernet defaults to 1500 because the data field is limited to 1500bytes [the IP packet sits within the Ethernet frames data field].
  14. fragmentation
    The dividing of IP datagrams to meet the MTU requirements of the Layer 2 protocol.
  15. TTL
    Time To Live

    Field in the IP header that prevents a packet from indefinitely looping around an IP internetwork.

    Routers decrease TTL field at each hop, once TTL=0 the packet is discarded.
  16. subnet aka subnetwork
    Group of IP addresses that have the same value in the first part of the IP address.

    For identifying a group by that part of the address.

    IP addresses with the same subnet are typically on the same network medium - not separated by routers.

    Short for subnetwork
  17. broadcast domain
    A logical network composed of all the computers and networking devices that can be reached by sending a frame to the data link layer broadcast address.
  18. hierarchical addressing
    Addressing scheme in which a network is partitioned into sections.

    Each section identifier forming one part of each destination's address and the destination identifier forming another.
  19. octets
    Group of 8 binary bits.

    Used to divide IPv4 addresses into four components.
  20. default gateway
    Device on a network that serves as an access point to other networks.

    Is used by a host to forward IP packets that have destination addresses outside the local subnet.
  21. routing table
    List that a router holds in memory for the purpose of deciding how to forward packets.
  22. default route
    Routing table entry that is used to direct frames for which a next hop is not explicitly listed in the routing table.

    Is used to forward a packet when no other known route exists for a given packet's destination address.
  23. static route
    Entry in an IP routing table that was created bc a network admin entered the routing config manually.
  24. dynamic routing
    Routing that adjusts automatically to network topology or traffic changes.
  25. routing protocols
    Protocol used between routers so they can learn routes to add to their routing tables.
Card Set
CCNA 1: Ch. 5 Vocab
CCNA 1: Ch. 5 Vocab