Cisco ASR 9000 Getting Started Manual page 167

Chapter
Internet Group Management Protocol. Governs the management of multicast groups in a TCP/IP
IGMP
network. Used by IP hosts to report their multicast group memberships to an adjacent multicast router.
Interior Gateway Protocol. Internet protocol used to exchange routing information within an
IGP
autonomous system. Examples of common Internet IGPs include IGRP, OSPF, and RIP. See also OSPF
and RIP.
Incoming channel.
ingress
The set of Cisco IOS XR software packages installed on a router.
installed software
set
The Cisco operating system used on the ASR 9000 Router, Cisco CRS router and
IOS XR
Cisco XR 12000 Series Router.
Internet Protocol. Network layer protocol in the TCP/IP stack offering a connectionless internetwork
IP
service. IP provides features for addressing, type-of-service specification, fragmentation and
reassembly, and security.
IP Version 4. Network layer for the TCP/IP protocol suite. A connectionless, best-effort packet
IPv4
switching protocol.
IP Version 6. Replacement for IPv4. A next-generation IP protocol. IPv6 is backward compatible with
IPv6
and designed to fix the shortcomings of IPv4, such as data security and maximum number of user
addresses. IPv6 increases the address space from 32 to 128 bits, providing for an unlimited number of
networks and systems. It also supports quality of service (QoS) parameters for real-time audio and
video.
Internetwork Packet Exchange. NetWare network layer (Layer 3) protocol used for transferring data
IPX
from servers to workstations. IPX is similar to IP and XNS.
Intermediate System-to-Intermediate System. OSI link-state hierarchical routing protocol based on
IS-IS
DECnet Phase V routing, whereby ISs (routers) exchange routing information based on a single metric
to determine network topology.
K
Period of time between each keepalive message sent by a network device.
keepalive interval
Message sent by one network device to inform another network device that the virtual circuit between
keepalive message
the two is still active.
L
Layer 2 refers to the data link layer of the commonly referenced multilayered communication model,
Layer 2
Open Systems Interconnection (OSI). The data link layer contains the address inspected by a bridge or
switch. Layer 2 processing is faster than layer 3 processing, because less analysis of the packet is
required.
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Cisco ASR 9000 Series Aggregation Services Router Getting Started Guide
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