3Com 2924-PWR Switch User Manual


 
240 APPENDIX F: GLOSSARY
Internet Control
Message Protocol
(ICMP)
A network layer protocol that reports errors in processing IP packets.
ICMP is also used by routers to feed back information about better
routing choices.
Internet Group
Management
Protocol (IGMP)
A protocol through which hosts can register with their local router for
multicast services. If there is more than one multicast switch/router on a
given subnetwork, one of the devices is made the “querier” and
assumes responsibility for keeping track of group membership.
In-Band Management Management of the network from a station attached directly to the
network.
IP Multicast Filtering A process whereby this switch can pass multicast traffic along to
participating hosts.
IP Precedence The Type of Service (ToS) octet in the IPv4 header includes three
precedence bits defining eight different priority levels ranging from
highest priority for network control packets to lowest priority for
routine traffic. The eight values are mapped one-to-one to the Class of
Service categories by default, but may be configured differently to suit
the requirements for specific network applications.
Layer 2 Data Link layer in the ISO 7-Layer Data Communications Protocol. This
is related directly to the hardware interface for network devices and
passes on traffic based on MAC addresses.
Layer 3 Network layer in the ISO 7-Layer Data Communications Protocol. This
layer handles the routing functions for data moving from one open
system to another.
Link Aggregated
Group (LAG)
Aggregates ports or VLANs into a single virtual port or VLAN.
Link Aggregation See Port Trunk.
Management
Information Base
(MIB)
An acronym for Management Information Base. It is a set of database
objects that contains information about a specific device.
MD5 Message Digest
Algorithm
An algorithm that is used to create digital signatures. It is intended for
use with 32 bit machines and is safer than the MD4 algorithm, which
has been broken. MD5 is a one-way hash function, meaning that it
takes a message and converts it into a fixed string of digits, also called
a message digest.