SAP bandwidth CAC

This feature provides a bandwidth CAC function per port or per LAG based on an admin bandwidth configured on a SAP and on the associated port or LAG. A booking factor is provided to allow over/under booking of the sum of the SAP bandwidth compared to the port/LAG bandwidth.

The admin bandwidth is an abstract value which could represent either, or both, of the ingress or egress bandwidth and is statically configured.

The goal of the CAC function is to ensure that the sum of the admin SAP bandwidth on a port or LAG does not exceed the admin bandwidth configured on that port or LAG.

This is supported on all service Ethernet SAPs, excluding PW SAPs, Ethernet tunnels and subscriber group interface SAPs. It is not supported in a VPLS or Epipe SAP template. It is applicable to both access and hybrid ports or LAGs; in the case of a hybrid port or LAG, the SAP CAC bandwidth only applies to the access operation.

By default a SAP, port or LAG has no admin bandwidth configured in which case it is excluded from the CAC function. Configuring an admin bandwidth on a SAP causes the CAC function to be enforced.

An admin bandwidth can only be configured on a SAP connected to a port or LAG which itself has an admin bandwidth configured. When a LAG is configured, the admin bandwidth and booking factor on its constituent ports are ignored.

The system tracks the requested and available bandwidth per port or LAG, where the available bandwidth is equal to the admin bandwidth on the port or LAG, with the booking factor applied, minus the sum of admin bandwidth configured on its SAPs. An attempt to increase a SAP's admin bandwidth fails if there is insufficient available bandwidth on its port or LAG.

The admin bandwidth and booking factor for the port or LAG is configured as follows:

configure
    lag <lag-id>
        access
            bandwidth <bw-value>
            booking-factor <percentage> 
    port <port-id>
        ethernet
            access
                bandwidth <bw-value>
                booking-factor <percentage>
    service
        [ cpipe | epipe | ipipe | vpls] <service-id>
            sap <sap-id>
                bandwidth <bw-value>
        [ies | vprn] <service-id>
            interface <ip-int-name>
                sap <sap-id>
                    bandwidth <bw-value>

Changes in admin bandwidth and booking factor are possible dynamically without having to disable the SAP, port or LAG.

After a SAP has been allocated bandwidth on a port or LAG that bandwidth is allocated to that SAP regardless of whether the SAP and, or port or LAG are up or down (either administratively or operationally). The admin bandwidth must be removed from the SAP configuration to free up its bandwidth on the port or LAG. Actions such as clearing the card or MDA, power-cycling the card or removing/inserting a card or MDA do not change the SAP and port or LAG CAC state.