LevelOne GEL-5261, User Manual

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Glossary
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IGMP Query
On each subnetwork, one IGMP-capable device will act as the querier — that is, the device
that asks all hosts to report on the IP multicast groups they wish to join or to which they
already belong. The elected querier will be the device with the lowest IP address in the
subnetwork.
IGMP Snooping
Listening to IGMP Query and IGMP Report packets transferred between IP Multicast Routers
and IP Multicast host groups to identify IP Multicast group members.
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.
LACP
Link Aggregation Control Protocol. Allows ports to automatically negotiate a trunked link
with LACP-configured ports on another device.
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.
LLDP
Link Layer Discovery Protocol is used to discover basic information about neighboring
devices in the local broadcast domain by using periodic broadcasts to advertise information
such as device identification, capabilities and configuration settings.
MD5
MD5 Message-Digest is 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.