Cabletron Systems MMAC-5FNB, Сетевое руководство

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Multi-Ring Configuration 6-33
Token Ring
Multichannel Token Ring
Token Ring bridging is an effective way of providing for the addition of users and
nodes to an existing or planned network, but the addition of several bridged
segments to a chassis with only one Token Ring backplane bus requires the use of
a bridging and management module any time a new ring is configured. While
Cabletron Systems does provide a bridging module for Token Ring networks
which fulfills this very function, the versatility of the FNB allows the creation of a
more capable and cost-effective Token Ring solution.
This multiple segment technology is based on the same concepts as the
Multichannel Ethernet architecture discussed earlier. In this case, the Token Ring
backplane of the MMAC-FNB chassis is divided into four separate rings, each
accessible from any point in the chassis by specific Token Ring modules. These
modules are the TRXMIM Token Ring Port Assignment modules and the
TDRMIM Token Ring Dual Repeater modules.
Each of these modules, in conjunction with a Multichannel Token Ring
Management Module such as the TRMM-4, can connect a front panel port or set
of ports to a specific backplane Token Ring bus, allowing four Token Rings to
operate within a single chassis, and using a single module to provide
management services for the networks.
The Multichannel Token Ring modules provide a capability called Port
Assignment, identical to that available for Ethernet networks. Port Assignment
allows the Network Manager to assign individual ports on the faceplates of the
TRXMIM modules to any of the backplane Token Ring buses through local or
remote management. In this way, a Port Assignment module could have two
users on ring 1, six users on ring 2, one user on ring 3, and 12 users on ring 4. If
someone needed to be moved to ring 1 from ring 3, a Network Manager could
simply notify the Media Interface Module to connect the port they are utilizing to
ring 1.
Token Ring Port Assignment MIMs, while more expensive than single-channel
Token Ring connectivity modules, give exceptional control and flexibility to the
Network Manager using them.
While Multichannel Token Ring Management Modules like the TRMM-4 allow
the MMAC chassis to support multiple Token Ring networks across a single,
unbroken backplane, the management modules themselves do not provide
bridging. Their function is to provide initialization, management, and monitoring
services. If you wish to connect the four networks that are created in an MMAC
chassis by a TRMM-4, for example, you will need to provide a separate bridging
or routing method.
TIP
TRXMIMs and TDRMIMs also support two internal standalone
rings. Ports may be assigned to these auxiliary rings for secure
file transfers or troubleshooting purposes. The auxiliary rings
do not communicate with other modules in the chassis.