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Glossary

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DVMRP

Distance Vector Multicast Routing Protocol: Based primarily on

the Routing Information Protocol (RIP), this Internet gateway protocol
implements a common, condensed-mode IP multicast scheme, using IGMP
to transfer routing datagrams between its neighbors. See also: IGMP.

DXI

Data Exchange Interface: Described in RFC 1482, DXI defines the

effectiveness of a network device such as a router, bridge, or hub to act as an
FEP to an ATM network by using a special DSU that accomplishes packet
encapsulation.

dynamic entries

Used in Layer 2 and 3 devices to create a table of either

hardware addresses or logical addresses dynamically.

dynamic routing

Also known as adaptive routing, this technique auto-

matically adapts to traffic or physical network revisions.

dynamic VLAN

An administrator will create an entry in a special server

with the hardware addresses of all devices on the internetwork. The server
will then assign dynamically used VLANs.

Generally used in Europe, a wide-area digital transmission scheme car-

rying data at 2.048Mbps. E1 transmission lines are available for lease from
common carriers for private use.

E.164

1) Evolved from standard telephone numbering system, the standard

recommended by ITU-T for international telecommunication numbering,
particularly in ISDN, SMDS, and BISDN. 2) Label of field in an ATM
address containing numbers in E.164 format.

E channel

Echo channel: A 64Kbps ISDN control channel used for circuit

switching. Specific description of this channel can be found in the 1984 ITU-
T ISDN specification, but was dropped from the 1988 version. See also:
B channel, D channel, and H channel.

edge device

A device that enables packets to be forwarded between legacy

interfaces (such as Ethernet and Token Ring) and ATM interfaces based on
information in the Data Link and Network layers. An edge device does not
take part in the running of any Network layer routing protocol; it merely
uses the route description protocol in order to get the forwarding informa-
tion required.

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