Workgroup Switches
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Product Overview
Available UFCs include:
• 4-Port Token-Ring Enhanced UTP/STP
• 2-Port Token-Ring Enhanced Fiber
• 1-Port ATM Token-Ring II MMF
• MMS Client MMF
• MSS Client SMF
• MSS Domain Client
Chassis-based for flexibility
Universal Feature Card slots allow
you to build a wide variety of switched
network configurations using the broad
set of optional feature cards that are
shared between both models. This set
of features provides copper and fiber
Token-Ring ports, high-speed uplinks
and Multiprotocol Switched Services
(MSS) Client support. This expands the
capabilities of the 8270 with a sophisti-
cated set of VLAN, filtering and Layer 3
switching functions. Unrestricted by a
fixed-port configuration, the UFCs can
be used in each of the slots of the IBM
8270 to construct a wide variety of
switched networks.
High-speed forwarding
When configured with the appropriate
number of Token-Ring Universal
Feature Cards, the 8270 provides high-
speed forwarding of Token-Ring frames
up to 30 shared or dedicated Token-
Ring LAN segments. Similar in function
to a multiport bridge, the 8270 forwards
Token-Ring frames from one of the 30
ports to another, based on Token-Ring
MAC addresses. The 8270 creates
multiple, parallel paths among the
connected Token-Ring LAN segments
and devices. Since each of these
parallel paths supports the full 16-Mbps
Token-Ring bandwidth, total bandwidth
of Token-Ring networks segmented
using the IBM 8270 could be expanded
by several hundred percent.
High-speed Token-Ring
Switching Solution
Growth in the number of networked
workstations and the increase power of
those workstations, allowing them to
use the growing number of data-
intensive applications such as
multimedia applications, continue to
place larger demands on Token-Ring
networks. LAN segmentation has been
a popular method for addressing these
demands. In addition, LAN segmenta-
tion has increased due to trends toward
server centralization. However, the
implementation costs of LAN segmen-
tation, as well as the real performance
characteristics of using conventional
network components, have served to
limit growth of some Token-Ring
networks. Other alternatives for
addressing bandwidth demands
present yet other inhibitors, usually
relating to costs. Token-Ring switching
provides users with an easy, cost-
effective technique for addressing
these demands.
TokenPipe support
Two or more 8270s can be connected
port-to-port, which effectively in-
creases the number of Token-Ring LAN
segments to be switched. These
interconnected 8270s form a single
“logical switch” called TokenPipe
support. This allows two 8270s to
communicate by connecting together
up to four full-duplex Token-Ring ports
on one 8270 to those on the other. With
multilink TokenPipes, traffic is automati-
cally distributed across the links within
a TokenPipe using destination address
so that traffic load can be more evenly
balanced across each of the parallel
links between switches. TokenPipe
support provides customers with the
ability to grow and tune the bandwidth
required between their 8270s and thus
within the LAN.
New features
Two new UFCs extend MSS forwarding
and routing services to the 8270 Nways
LAN Switch Family. Both the MSS Client
and MSS Domain Client Universal
Feature Cards (UFCs) provide forward-
ing and routing services. The MSS
Client also has an integrated ATM port
and provides ATM-to-LAN port bridging.
These client-function products
complete the MSS client/server family
and allow the MSS Server products to
perform their job in the network at
maximum efficiency. Along with virtual
LAN (VLAN) support by protocol,
OSI Layer 2 and 3 forwarding of IP, IPX,
AppleTalk and Banyan VINES protocols
are provided.
Cost-effective Token-Ring
switching
The IBM 8270 Nways Token-Ring LAN
Switch provides a cost-effective
solution to Token-Ring LAN perfor-
mance requirements. With a minimum
of disruption to existing networks,
you can significantly address LAN
performance.
A powerful LAN switch
With the 8270 you can build large
switched networks with high-speed
uplinks. A redundant power supply is
available to help ensure continuous
operation.
You can configure the versatile,
modular 8270 LAN switch to:
• Add from 4 to 30 ports to your network
configuration, more ports per switch
than any other model.
• Install uplink UFCs to connect native
protocols to high-speed links like high-
speed Token Ring, ATM or the IBM 8260
Nways Multiprotocol Switching Hub.
