IBM 8285 Nways, Installation And User Manual

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Switch/Control Point Functionality
The IBM 8285 Nways ATM Workgroup Switch integrates the same ATM switching functions and network
control functions that are used in the IBM 8260 hub, such as call setup processing, topology discovery,
and route selection.
ATM Switching Functions
The ATM Switch fabric switches ATM cells from one ATM port to another ATM port in the ATM
Workgroup Switch.
Control Point Functions
The ATM Workgroup Switch requires a control program (as do all ATM switching devices) to perform the
functions associated with the establishment and management of ATM circuits. These functions are
integrated into the switching element of each ATM Workgroup Switch.
ATM control functions are fully distributed instead of being centralized. This means that all nodes
participate as peers in the control algorithms. Distribution of control functions provide for availability,
scalability, and growth in an ATM network. The Control Point in each ATM Workgroup Switch provides
the following functions:
Control Plane Functions
Ÿ
Support of ATM signaling (SVCs) according to ATM Forum V3.1 specifications
Ÿ Switch-to-switch interface (SSI) based on an extension of the ATM Forum UNI V3.1 as stated in the
ATM Forum P-NNI framework
Ÿ
Topology services and route computation based on TRS, with automatic bypass of failed nodes and
links only for SSI connections (TRS is an extension of OSPF, Open Shortest Path First.)
Ÿ Interconnection of local ATM networks over an ATM WAN (‘SONET Lite’/P-NNI phase 0) that
provides a permanent virtual path, allowing switched connections to be set up between end systems
on both sides of the WAN (VP tunneling)
Ÿ
Internal SVC APIs to support node management and services over switched ATM connections
Ÿ Support of permanent virtual path (VP) and permanent virtual channel (VC) point-to-point
connections
Ÿ
Support of IP Over ATM (RFC 1577) for node management and services over a Classical IP
subnetwork; PING message: 916 bytes maximum
Ÿ Support of Ethernet (802.3) and Ethernet V.2 (DIX) LAN Emulation Client for node management and
services over a LAN Emulation subnetwork; PING and TELNET message: Maximum length depends
on the maximum SDU size supported on the corresponding emulated LAN (see Table 2 on page 15)
Ÿ Support of 802.3 and 802.5 LAN Emulation Servers and Broadcast Unknown Servers (LES/BUS)
Chapter 1. Introduction to the IBM 8285 Nways ATM Workgroup Switch
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