Cabletron Systems TRMM-4, User Manual

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INTRODUCTION
1-7
Ring Bypassing
With port switching MIMs (e.g., the TRXMIM), bypassing may also be
performed on a per ring basis. For example, a MIM’s Ring 3 channel may
be bypassed (i.e., isolated) from the FNB while the MIM’s Ring 1,
Ring 2, and Ring 4 channels remain connected to their respective FNB
channels. This is called a ring bypass. If all channels are bypassed from
the FNB the module is effectively in full module bypass.
Port Disabling
You can disable any port on any MIM in the MMAC, thus preventing any
device from using that port.
1.1.7 Network Interfaces
The TRMM-4 has four dedicated network interfaces, one for each
FNB ring. The TRMM-4 participates in all four interfaced networks
simultaneously, while still acting as a single network management agent
with a single IP address. Each interfaced network receives individual
management attention.
1.1.8 Ring Speed Assignments
The TRMM-4 assigns FNB ring speed settings (4 Mbps or 16 Mbps).
This sets the interface between MIMs and FNB rings. See
Section 2.3 for
details about the interaction of MIMs and the TRMM-4.
1.1.9 Automatic Configuration At Power-Up
The TRMM-4 stores operational parameters in its Non-Volatile RAM
(NVRAM). Whenever the TRMM-4 is powered-up or reset, it compares
the MIMs currently in the hub with those last registered. All MIMs
recognized throughout the hub are placed in management mode and
reconfigured according to settings stored in the NVRAM. Thus,
configuration settings stored before power-down are reinstated at the next
power-up.
Any MIM that is not recognized at power-up is allowed to operate in the
configuration dictated by its own hardware settings. The TRMM-4
observes the MIM’s configuration settings and stores them in NVRAM.