CANOGA PERKINS 9145E NID Software Version 4.10 - Manual (Page 281)

Bandwidth Profiling 9145E NID Software User’s Manual
Policers
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Figure 13-1 Bandwidth Profiling Algorithm
When a packet is received of size B bytes in length, the algorithm checks to see if there are at
least B tokens currently in the C bucket. If so, the C bucket is decremented by B and the packet
is forwarded on with a compliance level of Green. If there are less than B tokens in the C bucket,
the E bucket is checked to see if it has sufficient tokens. If the E bucket has at least B tokens,
then the packet is forwarded on with a compliance level of Yellow. If both the C and E buckets
have insufficient tokens, the packet is said to have a compliance level of Red, and is discarded.
13.2 Policers
Policers limit the ingress traffic on User Ports, according to an associated bandwidth profile.
There are a maximum of 127 policers.
A policer is created and destroyed by the system and has the following attributes:
• a unique numerical policer ID
• a textual name
• a bandwidth profile record attached to the policer. Several policers may share the same
bandwidth profile.
• the traffic flow type that is policed. A policer may be associated with:
• a Port - a port level policer will enforce a specific bandwidth profile to all the traffic
ingressing from the user port. If a policer is associated with a Port, no other polic-