LevelOne GTL-2690 User Manual
Page 777

Glossary
Glossary-4
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 Aggregation
See Port Trunk.
Link Aggregation Control Protocol (LACP)
Allows ports to automatically negotiate a trunked link with LACP-configured ports on 
another device.
Management Information Base (MIB)
An acronym for Management Information Base. It is a set of database objects that 
contains information about a specific device.
