Specifications

Glossary–12
protocol filtering (MAC layer)
A feature in some bridges that can be programmed to forward or reject transmissions
that are originated under specified MAC protocols.
proxy access
The way a proxy Simple Network Management Protocol (SNMP) agent provides
requests to the network management station (NMS). A proxy agent acts on behalf of
network devices that do not support SNMP. When such a network module is to be
managed, the NMS contacts the proxy agent and indicates the identity of the network
module.
proxy agent
The proxy agent translates the protocol interactions it receives from the network
management station into whatever interactions are supported by the network module.
rate limit
The total number of frames on all ports allowed by a bridge per second.
repeat
An action in which a station receives a frame or token from an upstream station,
retimes it, and places it onto the ring for its downstream neighbor. The repeating sta-
tion can examine, copy to a buffer, or modify control bits in the frame, as appropri-
ate.
repeater
A level 1 hardware device that restores signal amplitude, waveform, and timing of
signals before transmission to another network segment.
responder mode
This mode designates ports that connect to master mode ports. Responder ports are
always enabled but are active only when their master port is active. A key function of
the responder port, other than receiving and transmitting data, is to report link fail-
ures to the master port. When the master port detects a link failure, it causes the link
to failover to the standby link. If the standby link is not available when the active link
fails, the failover process waits until it is available. If the previously active link
becomes available during this waiting period, the master returns to using it. Other-
wise, the failover to the standby link takes place as soon as the standby link is good.
Thus, the highest utilization possible on a dual-port redundant link is achieved.