Rate Limiting
Adaptive Rate Policy for a Specific MAC Address
Figure 4.3 shows an example of a rate policy consisting of one rule applied to a virtual routing interface (“virtual interface” or “VE”). A virtual interface enables ports in a VLAN to route to other VLANs. In this example, the VLAN contains three ports, attached to three hosts. The hosts use virtual interface ve2 for routing.
The rate policy in this example forwards all conforming traffic from the host with MAC address aaaa.bbbb.cccc but drops all additional traffic from the host. Conforming traffic is traffic within the Normal Burst Size specified in the rate policy. Within a given Committed Time Interval, if the host sends more bytes than the number of bytes allowed by the Normal Burst Size, the policy drops the excess bytes.
The other hosts in the VLAN do not have rules. As a result, their bandwidth is not limited.
Internet
Internet access router
Rate Policy for ve2
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Inbound IP traffic to MAC address aaaa.bbbb.cccc
The hosts are in a VLAN that uses routing interface ve2.
MAC address aaaa.bbbb.cccc
Figure 4.3 Adaptive Rate Limiting applied to virtual routing interface
The rule could be applied to the port attached to the host for the same results. However, since the rule is associated with the virtual interface instead of a physical port, the policy remains in effect even if the host moves to another port within the VLAN.
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