IBM 8265 Nways ATM Campus Switch - IBM Redbooks

1.4 Switching Architecture
• All ATM modules are hot-swappable. Any module can be removed or
inserted without having to power down the hub.
• Each backplane can support up to two A-CPSW modules for reliability and
redundancy.
• Certain 8260 ATM media modules can fully coexist with 8265 module.
One can install 8265 media modules in slots 1 to 8 and 12 to 17 of an 8265
equipped with a single A-CPSW module, or in slots 1 to 8 and 13 to 17 of an 8265
equipped with two A-CPSW modules. One can also install a single A-CPSW in
slot 11-12, but then only slots 1-8 and 13-17 can be used for media modules, thus
losing one slot.
When two A-CPSW modules are installed for redundancy, a serial interface on
the 8265 backplane links the two A-CPSWs together (Figure 3 on page 6). This
interface is used by the two control points (primary and secondary) to update
automatically any configuration changes and to monitor the health of the primary
for A-CPSW redundancy. The A-CPSW redundancy method is covered in 2.2,
“ATM Control Point and Switch Module (A-CPSW)” on page 14.
A frontal wrong slot LED is provided on the modules to indicate incorrect
insertion of a module into the chassis.
1.3.2.1 Burnt-In MAC Addresses
The ATM backplane has three burnt-in MAC addresses, for use by the ATM
control point. These addresses are used for:
• Token-ring LAN Emulation client
• Ethernet LAN Emulation client
• A-CPSW Ethernet management service port
These burnt-in MAC addresses should simplify the initial setup of 8265 ATM
switches. By putting these MAC addresses on the chassis rather than on the
A-CPSW module itself, it simplifies maintenance. For example, in the case of
swapping A-CPSW modules, the identity of the ATM switch remains unchanged.
1.3.2.2 Pin Description
The power and management backplane is composed of 96 female pin
connectors, arranged in a matrix form of 3 rows and 32 columns.
The ATM backplane is composed of 110 male pin connectors, arranged in a
matrix form of 5 rows and 22 columns.
In comparison, the backplane for 8260 ATM modules is composed of 120 female
pin connectors, arranged in a matrix form of 5 rows and 24 columns.
The 8265 ATM switching architecture, has a central switching fabric with
distributed buffer pools and traffic management.
The main hardware components of the switching architecture are shown in
Figure 4 on page 8:
• The switch (with the control point)
• The ATM engines (on the media module)
Chapter 1. 8265 Product Specification 7