[TechView: Communications]
Access Processor Aggregates Multiple Protocol Traffic For Carrier Ethernet Transmission
Louis E. Frenzel
ED Online ID #18330
March 13, 2008
Copyright © 2006 Penton Media, Inc., All rights reserved. Printing of this document is for personal use only.
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An excess of acronyms represents the protocols used in carrying
various types of data traffic. Nowhere is this more profound
than in cellular communications, where basestations must
maintain the older legacy protocols as well as implement all the
new ones. The challenge in making equipment that can handle
this job lies in pulling all those different protocols together and
transmitting them over a lower-cost medium.
That lower-cost medium is gradually emerging as carrier Ethernet
that can replace older T1-E1/ATM/Sonet systems, which
work well but are very expensive. Wintegra, a provider of packet
processors and software for wireless and wireline infrastructure
equipment, now has a way to aggregate all that data into a manageable
format. Its WinIP family of IP-only silicon and software
provides the intelligence and upgradeablility for infrastructure
equipment to support the emerging networks based on the convergence
of voice, video, data, and wireless services.
The WinIP solution combines a network processor optimized
for access and aggregation and the related software. It suits
emerging carrier Ethernet applications such as wireless backhaul
connectivity between wireless basestations, wireless Long-Term
Evolution (LTE) transport, and Metro Ethernet access.
However, the migration to an all-IP network doesn’t simplify
the protocol processing requirements in new equipment. Simple
switches aren’t sufficient to provide advanced encapsulation
such as MPLS, L2TP, GRE, and Ethernet pseudo-wire. Additionally,
they aren’t sufficient to handle quality-of-service (QoS)
features such as shaping, policing, and remarking IP packets
needed by carriers to offer service-level agreements (SLAs) to
their customers.
With a WinIP processor and Wintegra’s array of free protocol
processing software, though, vendors can build a cell-site
aggregator that packages all the T1/E1, ATM, OC3, AAL2/5,
PPPmux, ML-PPP, and other protocols into carrier Ethernet for
cost-efficient transmission to the central office. These multicore
processors contain both data-path and control-path processing
(see the figure).
The control path uses a 24k MIPS core running at up to 600
MHz, while the data path uses up to six 350-MHz Wintegra
proprietary data engines optimized for data handling. The initial
devices support up to four 1-Gbit Ethernet (GbE) ports or 24
Fast Ethernet ports. The memory is external so its size can be
optimized to the application.
The processors can use DDR-I
or DDR-II SDRAM or SRAM
with error correction coding
(ECC) support. The WinIP
devices have on-board hardware
accelerators for shaping, integrated
encryption support, and testdata-
in (TDI) clock generation
circuitry. Other interfaces include
PCI 2.2, POS2, or SPI.3 and up to
four serial TDI ports.
The free software that’s included
saves a massive amount of time
and cost in new product development.
Support includes PPPoA/PPPoE, bridging/routing/switching, GRE/GTP, L2TP, and synchronous
Ethernet. QoS support includes Ethernet OAM, BFD/
VCCV, packet classification, hierarchical shaping, WRED, statistics/
billing, and 2 Rate 3-Color marking.
Advanced L2 protocols are all available. Wintegra’s supplied
Carrier Grade-Wintegra Device Driver Interface facilitates
interfacing with your own software. Two of the planned chips and
all of the software are available now.
WINTEGRA • www.wintegra.com
See associated figure
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