Cabletron Systems Netlink FRX4000, User Manual

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Glossary glos-5
I
ICMP
stands for “internet control message protocol,” which handles IP error and control
messages. Gateways and hosts use ICMP to report problems concerning datagrams
back to the source.
Internet
is an interconnected group of packet-switching networks, joined by gateways sup-
porting the TCP/IP protocol. The term also refers to the DARPA (Defense Advanced
Projects Research Agency) Internet.
Internet Protocol
is the Internet standard protocol that defines the datagram as the basic unit of data
transmitted across the internet.
IP
stands for “internet protocol.”
IPL
stands for “initial program load,” which is the loading into a node of the operating
software on power-on or re-boot.
IPX
stands for “Internetwork Packet Exchange,” which is a Novell NetWare connec-
tionless protocol that defines internetwork and intranode addressing schemes.
L
LAN
stands for “local area network,” which is a network operating over short distances at
high speeds.
LCN
stands for “logical channel number,” which is used as an identifier for a virtual circuit
between a DTE and a DCE.
Level 2
is the link layer in the ISO (International Standards Organization) 7-layer OSI (Open
Systems Interconnect) reference model.
Level 3
is the packet layer in the OSI reference model.
Line Interface Card
is a four-port “daughter” card attached to an FRX6000 RLP, or mounted in an
FRX4000, and containing the components that support a hardware interface: RS-232/
V.28, V.35, or RS-422/V.11.
LLC
stands for “logical link control,” which is the third layer in the three-layer ISO LAN
protocol hierarchy. (The first two layers are Physical and MAC; MAC is described in
this glossary.) LLC is responsible for addressing and data link control.