Avaya P580 - Manual (Page 161)

Avaya P550R, P580, P880, and P882 Multiservice Switch User Guide, Version v5.3.1 4-31
Using VLANs, Spanning Tree, Hunt Groups, and VTP Snooping
Fabric Ports
The P580/P882 has two backplane connections or ports for each
media module. These ports connect the media modules to the
backplane Cross Bar Switch Fabric, which in turn connects all
modules to all other modules and ports. These ports are referred to
as “Switch Fabric Ports”. There are two Switch Fabric ports per
media module slot (slots 2 through 7, or slots 2-17) and one fabric
port for the Supervisor slot (slot 1) (Figure 4-18).Each 80 series
media module can use up to two fabric ports in the slot, the number
of Forwarding Engines to fabric ports varies with the media
module.There is anywhere from one to four Forwarding Engines per
fabric port for each 80 series media module (Table 4-7).
The number of Forwarding Engines are distributed among the ports
for 80 series modules. The 80 series 10/100 Mbps media modules
are distributed with 12 10/100 ports for each Forwarding engine.
For example, the 48 port 10/100 media module has four Forwarding
Engines. The first 12 (1-12) ports are on the first Forwarding Engine,
the second 12 (13-24) are on the second Forwarding Engine, which
in turn use one fabric port, the third and fourth grouping of 12 ports
each have a Forwarding Engine and use the second fabric port. The
Forwarding Engines are distributed on a one to one basis for the 80
series Gigabit media modules. For example the 8 port 1000 TX, the
first four ports have four Forwarding Engines, one for each Gigabit
port (1-4), and uses one fabric port, the other four ports (5-8) also
have four Forwarding Engines, which use the second fabric port.
50 Series
Forwarding
Engines and
Fabric Ports
On a 50 series layer 3 module, each fabric port has two Forwarding
Engines, one for layer 3 traffic, and one for layer 2 traffic. All layer 3
traffic will be associated with one Forwarding Engine and all the
layer 2 traffic will be associated with the other Forwarding Engine.
Example, the twelve-port 10/100 layer 3 50 series media module,
layer 3 traffic is coming in the first port and the last port, (ports
1,12). Using the 80 series even distribution, the first six ports are
associated with one FE and the second six ports with the second FE,
and distributed across both fabric ports.
This is different for the 50 series modules. The twelve port layer 3 50
series media module, all twelve ports are associated with one
Forwarding Engine for layer 3 traffic and one Forwarding Engine for
layer 2 traffic. In addition only one fabric port is used for all twelve
ports.