Bandwidth Control Overview - ZyXEL Communications ENC User Manual

Table 101 Port Management > Basic Setting > View Status (continued)
LABEL
TxPkts
RxPkts
Errors
TxKB/s
RxKB/s
Refresh
Close
8.4.2.1 STP Port States
STP assigns five port states to eliminate packet looping. A bridge port is not allowed to go directly from blocking
state to forwarding state so as to eliminate transient loops.
Table 102 STP Port States
PORT STATE
Disabled
Blocking
Listening
Learning
Forwarding

8.4.3 Bandwidth Control Overview

Bandwidth control means defining a maximum allowable bandwidth for incoming and/or out-going
traffic flows on a port.
8.4.3.1 CIR and PIR
The Committed Information Rate (CIR) is the guaranteed bandwidth for the incoming traffic flow on
a port. The Peak Information Rate (PIR) is the maximum bandwidth allowed for the incoming traffic
flow on a port when there is no network congestion.
The CIR and PIR should be set for all ports that use the same uplink bandwidth. If the CIR is
reached, packets are sent at the rate up to the PIR. When network congestion occurs, packets
through the ingress port exceeding the CIR will be marked for drop.
Note: The CIR should be less than the PIR.
Note: The sum of CIRs cannot be greater than or equal to the uplink bandwidth.
8.4.3.2 Bandwidth Control Setup
To open this screen, select a device which supports this feature from the OTV, Device View or Group
View panel and click Application > Port Management > Bandwidth Control.
ENC User's Guide
DESCRIPTION
This field shows the number of transmitted frames on this port.
This field shows the number of received frames on this port.
This field shows the number of received errors on this port.
This field shows the number of kilobytes per second transmitted on this port.
This field shows the number of kilobytes per second received on this port.
Click this to update this screen.
Click this to exit this screen.
DESCRIPTION
STP is disabled (default).
Only configuration and management BPDUs are received and processed.
All BPDUs are received and processed.
The listening state does not exist in RSTP.
All BPDUs are received and processed. Information frames are submitted to the learning
process but not forwarded.
All BPDUs are received and processed. All information frames are received and
forwarded.
Chapter 8 Application
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