3Com SUPERSTACK 3 3250, Implementation Manual

Page: 53 / 132

Limiting the Rate of a Port 53
Configuring rate limiting
Rate limiting can be configured on your Switch using the Web interface
or the Command Line Interface (CLI).
Rate limiting can be applied in steps of 1 Mb on 10/100 ports and in
steps of 8 Mb on 10/100/1000 ports.
For a detailed description of the commands that you require to configure
rate limiting refer to the
Management Interface Reference Guide supplied
in HTML format on the CD-ROM that accompanies your Switch.
Traffic Prioritization
and Rate Limiting
Traffic prioritization and rate limiting can be used together to effectively
manage the traffic on your network:
■
Rate limiting will ensure that the traffic on a connection never exceeds
the rate you specify.
■
Traffic prioritization will ensure that any packets dropped at times of
network congestion are of the lowest priority.
Traffic prioritization and rate limiting are most effective together if the
egress rate rather than the ingress rate is limited on a port; that is the
traffic rate leaving the Switch is limited rather than the traffic arriving at
the Switch. This ensures that the traffic is prioritized before rate limiting is
applied, and that the lowest priority packets are dropped first.
Rate limiting on ingress, as the packets arrive at the port is not as
effective. The Switch cannot determine the order in which packets will
arrive and will not filter by priority.