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CrossFire 8650/8651 UEM Guide to Operation, DOC-7090 v. 1.0
3. Console Configuration
Introduction
The CrossFire 8650 and 8651 UEMs have two 100 Mbit HSTR ports. In the console
configuration, port numbers are used to refer to ports, with the ordinary
Token-Ring ports being numbered 1 to 20. If the module is inserted into the left
expansion slot, the HSTR ports are number 21 and 22. If the module is inserted into
the right expansion slot, the HSTR ports are number 25 and 26. Any number of
CrossFire 8650 and 8651 UEMs can be inserted into a stack of Token-Ring
switches.
The HSTR ports are configured much like ordinary Token-Ring ports, and
generally appear in all tables where ordinary Token-Ring ports appear.
Ports, Port Groups and VLANs
This section briefly describes the VLAN concept and switching modes of the
CrossFire 8600 or 8605 Switches. For more information about these subjects,
please refer to the
CrossFire 8600/8605 Token-Ring Switches Guide to Operation.
The CrossFire 8600 and 8605 Switches support up to 63 VLANs. A VLAN forms
a single bridged domain. The visibility of MAC addresses, bridge and ring numbers
as well as the scope of broadcast frames are limited to the VLAN in which they
origin. Frames must be routed to move between VLANs.
A VLAN consists of a number of port groups called Concentrator Relay Function
(CRFs). A CRF is conceptually equal to a ring. If a VLAN contains two or more
CRFs they are conceptually connected by a multiport bridge called a Bridge Relay
Function (BRF).
The BRF performs either Source-route bridging (SRB) or Source-route transparent
(SRT) switching between the CRFs depending on the CRF configuration. The
CRFs configured for SRT switching form a SRT domain, in which source-routed
frames are source routed and non-source-routed frames are transparently switched.
Each ordinary Token-Ring port is assigned to a specific CRF, which also
determines which VLAN it belongs to.
HSTR Virtual Ports and VLAN Tagging
The HSTR ports behave much like ordinary Token-Ring ports. They implement the
DTR TXI MAC layer protocol as specified in the IEEE 802.5t specification and can
be configured for
Port
,
Station
or
Auto
sensing modes. Also, before a port is
inserted, the MAC layer protocol must complete the lobe test, which verifies the
cable connection.
HSTR ports differ significantly from ordinary Token-Ring ports, however, in that
HSTR ports can function as trunk ports, which means that they can carry traffic
belonging to all possible 63 VLANs over the same physical cable connection.
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