3Com 3C17300-US - SuperStack 3 Switch 4226T, Implementation Manual

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IGMP snooping A mechanism performed by an intermediate device, such as a Layer 2
Switch, that optimizes the flow of multicast traffic. The device listens
for IGMP messages and build mapping tables and associated
forwarding filters, in addition to reducing the IGMP protocol traffic.
Internet Group
Management
Protocol
Internet Group Management Protocol (IGMP) is a protocol that runs
between hosts and their immediate neighboring multicast routers. The
protocol allows a host to inform its local router that it wishes to receive
transmissions addressed to a specific multicast group. Based on group
membership information learned from the IGMP, a router is able to
determine which if any multicast traffic needs to be forwarded to each
of its subnetworks.
Intranet An Intranet is an organisation wide network using Internet protocols
such as web services, TCP/IP, HTTP and HTML. An Intranet is normally
used for internal communication and information, and is not accessible
to computers on the wider Internet.
IP Internet Protocol. IP is a layer 3 network protocol that is the standard
for sending data through a network. IP is part of the TCP/IP set of
protocols that describe the routing of packets to addressed devices.
IPX Internetwork Packet Exchange. IPX is a layer 3 and 4 network protocol
designed for networks that use Novell
®
Netware
®
.
IP address Internet Protocol address. A unique identifier for a device attached to a
network using TCP/IP. The address is written as four octets separated
with periods (full-stops), and is made up of a network section, an
optional subnet section and a host section.
Jitter An expression often used to describe the end-to-end delay variations
during the course of a transmission. See also
latency .
LAN Local Area Network. A network of endstations (such as PCs, printers,
servers) and network devices (hubs and switches) that cover a relatively
small geographic area (usually not larger than a floor or building). LANs
are characterized by high transmission speeds over short distances (up
to 1000 m).
LLC Logical Link Control. A sublayer of the IEEE data link layer that is
located above the MAC sublayer. The LLC sublayer is responsible for
MAC sublayer addressing, flow control, error control, and framing.
dua1730-0bAA03.book Page 113 Monday, July 11, 2005 11:14 AM