LAN Emulation Overview
12-5
Q
Physical Layer
Q
ATM Layer
Q
ATM Layer Statistics
Q
Virtual Path Connections (VPC)
Q
Virtual Channel Connections (VCC)
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Address Registration Information
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Service Registry Table
ATM Address
Registration
In order to establish an ATM connection at the UNI, both the user and the
network must know the ATM addresses which are in effect at that UNI.
These ATM addresses can then be used in signaling messages for
establishing connections with a specific ATM end system. The address
registration procedure provides the means for the dynamic exchange of
addressing information between the user and the network at the UNI, at
initialization and at other times as required.
LAN Emulation
Overview
LAN Emulation
(LE) is a method of connecting LAN users over an ATM
network which enables them to communicate with each other as if they
were operating over traditional LANs. LE can be configured in a ATM
network in several ways:
Q
To connect legacy end stations directly to other legacy systems, as well
as to servers, routers, switches and other networking devices attached
to the ATM network.
Q
To connect bridged-LAN environments to each other over ATM. In this
case the Emulated LAN acts as a bridge on the ATM network.
Q
To connect ATM end stations to each other, enabling communication
between them.
Emulated LAN
Components
LAN Emulation is implemented as a set of connection services collectively
called an
emulated LAN
(ELAN). Each ELAN is a composed of a set of
LAN
Emulation Clients
(LEC) and a single LAN Emulation Service. The latter
consists of an
LE Configuration Server
(LECS), an
LE Server
(LES), and a
Broadcast and Unknown Server
(BUS). Each LE Client is incorporated in
an ATM end station, such as a SuperStack II Switch 2700 or 7600 Card,
and represents a set of LAN users, identified by their MAC addresses. The
abtthgde.book Page 5 Tuesday, June 23, 1998 10:29 AM