IBM SG24-4817-00 - Manual (Page 22)

This soft copy for use by IBM employees only.
To avoid having to configure the LES
′
s address at each endstation, LANE
provides for a Lan Emulation Configuration Server (LECS), which LECs can query
for their proper LES address. This enables backup LESs to be configured, since
should the primary LES fail, the LECS merely has to direct connections to a
backup LES without having to change any configuration in the workstation.
Although the 8285 ATM Control Point does not contain an LECS, either or both of
the internal LECs can be configured to use an external LECS, such as that
provided by the IBM Multiprotocol Switched Services Server.
This section was intended only as an overview of LANE. For a more detailed
description of these functions, please see
IBM 8260 As a Campus ATM Switch,
SG24-5003 and ATM Campus Introduction, Planning, and Troubleshooting
Overview, GA27-4089.
1.1.4.3 Classical IP (CIP)
Figure 4. ATM Classical IP using ARP Server
Classical IP (RFC 1577) is a protocol-specific VLAN (PVLAN) technology that has
been widely adopted in the Internet working community. It provides for layer 3
routing of IP datagrams over an ATM network. In many ways, it is analogous to
LANE. For instance, all endstations must register with an address resolution
server (called a LES in LANE, but an
Address Resolution Protocol (ARP) Server
in CIP). Once the endstation is registered with the address resolution server, it
is, by definition, part of a virtual broadcast domain (an ELAN in LANE
terminology, but a VLAN in CIP, known as a
Logical IP Subnet (LIS)). The 8285
ATM Control Point has a single CIP client entity.
Here are the CIP data flows:
6
ATM Workgroup Solutions: Implementing the 8285 ATM Switch