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Glossary
IGRP
Interior Gateway Routing Protocol: a Cisco
proprietary routing protocol that uses a distance-vec-
tor algorithm. It uses a vector (a one-dimensional
array) of information to calculate the best path. This
vector consists of four elements: bandwidth, delay,
load, reliability.
ILMI
Integrated (or Interim) Local Management
Interface. A specification created by the ATM Forum,
designated for the incorporation of network-manage-
ment capability into the ATM UNI. Integrated Local
Management Interface cells provide for automatic
configuration between ATM systems. In LAN emula-
tion, ILMI can provide sufficient information for the
ATM end station to find an LECS. In addition, ILMI
provides the ATM NSAP (Network Service Access
Point) prefix information to the end station.
in-band management
In-band management is the
management of a network device "through" the net-
work. Examples include using Simple Network Man-
agement Protocol (SNMP) or Telnet directly via the
local LAN. Compare with: out-of-band management.
input queues
These queues reside on the RP, and
they are used to link the SP buffers to the RP buffers.
The queue reserves RP buffer space for a packet that
was forwarded from the SP/SSP. If the Router Proces-
sor doesn't process the queued packets at the same
rate, the queue fills up and the incoming packets are
dropped.
inside-out troubleshooting
This method of trou-
bleshooting directs the troubleshooter to start near the
user and work their way toward the far end of the area
of dysfunctionality.
insured burst
In an ATM network, it is the largest
temporarily permitted data burst exceeding the
insured rate on a PVC and not tagged by the traffic
policing function for being dropped if network con-
gestion occurs. This insured burst is designated in
bytes or cells.
interarea routing
Routing between two or more
logical areas. Contrast with: intra-area routing. See
also: area.
interface buffer
A buffer used for intermediate stor-
age. Packets from all of the hardware buffers are cop-
ied to the interface buffers. The switch processor
houses the intermediate buffers by using 512KB for
the SP board memory. This memory is also shared
with the autonomous switching cache.
interface processor
Any of several processor mod-
ules used with Cisco 7000 series routers. See also: AIP,
CIP, EIP, FEIP, HIP, MIP,
and TRIP.
Internet
The global "network of networks," whose
popularity has exploded in the last few years. Origi-
nally a tool for collaborative academic research, it has
become a medium for exchanging and distributing
information of all kinds. The Internet's need to link
disparate computer platforms and technologies has
led to the development of uniform protocols and stan-
dards that have also found widespread use within cor-
porate LANs. See also: TCP/IP and MBONE.
internet
Before the rise of the Internet, this lower-
case form was shorthand for "internetwork" in the
generic sense. Now rarely used. See also: internet-
work.
Internet protocol
Any protocol belonging to the
TCP/IP protocol stack. See also: TCP/IP.
internetwork
Any group of private networks inter-
connected by routers and other mechanisms, typically
operating as a single entity.
internetworking
Broadly, anything associated with
the general task of linking networks to each other. The
term encompasses technologies, procedures, and
products. When you connect networks to a router,
you are creating an internetwork.
intra-area routing
Routing that occurs within a
logical area. Contrast with: interarea routing.
Inverse ARP
Inverse Address Resolution Protocol:
A technique by which dynamic mappings are con-
structed in a network, allowing a device such as a
router to locate the logical network address and asso-
ciate it with a permanent virtual circuit (PVC). Com-
monly used in Frame Relay to determine the far-end
node's TCP/IP address by sending the Inverse ARP
request to the local DLCI.
IP
Internet Protocol: Defined in RFC 791, it is a Net-
work layer protocol that is part of the TCP/IP stack
and allows connectionless service. IP furnishes an
array of features for addressing, type-of-service speci-
fication, fragmentation and reassembly, and security.
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