26
Ethernet Routing Switch 8600 module fundamentals
•
One Fast TAPmux (FTAP) interface to the fabric modules
•
One Feedback Output Queueing (FOQ) Manager Field-Programmable
Gate Array (FPGA)
The FTAP ASIC interfaces each DPM to the switch fabric/CPU (SF/CPU)
modules through the Ethernet Routing Switch 8600 switching backplane.
The FOQ management system collects information about the state of
queues, packet storage elements, and the fabric. This information is
available to the F
2
I at the point where packets are segmented for entry
to the fabric. When congestion exists, BFM modules use fabric feedback
information from this point to drop packets.
FOQ also provides information about the state of each egress queue and
the fullness of the F
2
E reassembly function buffers and queues. The F
2
E
reports this information to the FOQ Manager FPGA on each module. The
constellation of these FOQ FPGAs (one for each DPM) drives a shared
backplane bus that each FPGA senses. Therefore, each R module can
access pertinent information about the state of all other R modules in the
system.
Among R modules, the 8648GTR is potentially 2.4:1 oversubscribed on
both lanes; the 8630GBR, the 8683XLR and the 8683XZR all operate at
line rate.
Release 5.x module feature set
Release 5.0 adds support for four new modules, termed RS modules. RS
modules use a two or three-lane forwarding module called the Distributed
Processing Module 2 (DPM2). Architecturally, the DPM2 is based on the
R module DPM. The DPM2 provides three flexible forwarding engines and
uses RSP version (RSP2.6), F
2
E version (2.1), a co-processor, FPGAs,
and surrounding logic.
All RS modules have built-in priority queueing. All RS modules support
jumbo frames.
RS modules are comprised of two parts: the Port Interface Module (PIM)
and the DPM2. The PIM is an interface option daughter-card and requires
the DPM for configuration, power, and forwarding engine support.
Use RS modules to provide high port density and data rates, as well
as enhanced port mirroring and custom Auto-Negotiation (CANA)
functionality.
Nortel Ethernet Routing Switch 8600
Installation — Modules
NN46205-304
02.02
Standard
16 June 2008
Copyright © 2008 Nortel Networks
.
Summary of Contents for Passport 8600 Series
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