Ruckus Wireless Ruckus ICX 7150 Series, Руководство по настройке

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How port-based fixed rate limiting works
The following figure shows an example of how fixed rate limiting works. In this example, a fixed rate limiting policy is applied to a port to limit
the inbound traffic to 500000 bits (62500 bytes) a second. During the first two one-second intervals, the port receives less than 500000 bits
in each interval. However, the port receives more than 500000 bits during the third and fourth one-second intervals, and consequently
drops the excess traffic.
FIGURE 3 Fixed rate limiting
NOTE
The software counts the bytes by polling statistics counters for the port every 100 milliseconds, which provides 10 readings each
second. As such, the fixed rate limiting policy has an accuracy of within 10% of the port's line rate. It is possible then for the policy
to sometimes allow more traffic than the limit you specify, but the extra traffic is never more than 10% of the port's line rate.
CPU rate limiting
CPU rate limiting is a CPU protection scheme that limits certain traffic types.
Unnecessary traffic to the switch CPU lowers the efficiency of the CPU and delays handling of other traffic that requires processing. CPU
rate limiting identifies the traffic type and assigns a maximum rate limit to the traffic type. The traffic types which are subjected to rate limiting
include broadcast ARP and other exceptions, such as TTL exceed, IP MTU failed, reverse path check failed, IP fragments, and unsupported
tunneling. Each of these types is rate-limited individually.
The following table shows the rate limits for each rate-limited packet type. You cannot configure these rates.
All currently supported FastIron devices support the CPU rate-limiting feature.
Rate Limiting and Rate Shaping
Rate Limiting
Ruckus FastIron QoS and Traffic Management Configuration Guide, 08.0.70
52 Part Number: 53-1005294-01