IBM 8285 Nways, Installation And User Manual

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LAN Emulation Over ATM
The IBM 8285 Nways ATM Workgroup Switch supports LAN emulation, as defined in ATM Forum
specifications, using two different servers:
Ÿ LAN Emulation Server (LES)
Ÿ Broadcast and Unknown Server (BUS)
The LAN emulation servers are integrated in the IBM 8285 Nways ATM Workgroup Switch Control Point,
and they are configured and operate in tandem.
The IBM 8285 Nways ATM Workgroup Switch also includes a basic LAN Emulation Client (LEC) and
supports external LAN Emulation Configuration Servers (LECSs).
Highlights
IBM’s implementation of LAN emulation in the ATM Workgroup Switch complies with Version 1.0 of the
ATM Forum specifications for LAN emulation, and supports:
Ÿ Both 802.5 (Token Ring) and 802.3/Ethernet V.2 (DIX) LAN types for the LES/BUS.
Ÿ Up to two separate emulated LANs simultaneously, of the same or different LAN types.
Ÿ 802.3 LAN types for the LEC.
Ÿ Both UNI 3.0 and 3.1 LECs, concurrently.
Ÿ Up to 128 LECs (combined total).
Ÿ LES addresses that are either configured directly in each LEC or supplied through a dialog with an
external LECS.
Ÿ LECS locations that may be:
– Set to the well known anycast LECS ATM address
– Supplied by the LECS ATM address field in the ILMI MIB
– Set to the well known PVC (VPI=0, VCI=17)
Ÿ All maximum frame sizes defined in ATM Forum specifications:
– Control frames: 1516 octets
– Data frames: 1516, 4544, 9234, 18190 octets
Ÿ Best Effort connections with Quality of Service set to 0. Bearer classes supported are:
– BCOB-X and BCOB-C for incoming calls
– BCOB-X for outgoing calls.
IBM’s current implementation of LAN emulation does not support:
Ÿ
Communication over PVCs
Ÿ Internal LECS
Ÿ
Broadcast Manager, which is not standardized.
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IBM 8285 Nways ATM Workgroup Switch: Installation and User’s Guide