Automatic PBB tunnel binding

Overview

This feature is applicable only to VLL Epipes and I-VPLS services using a PBB tunnel.

The configuration of the service CAC functionality allows you to manage bandwidth at the service level and at the link level, which in turn enables the NFM-P to automatically select the best tunnel based on the number of active links and on the amount of available bandwidth on the service. The NFM-P also considers the shortest available path when it allocates bandwidth.

Although the NFM-P can select tunnels automatically—see Automatic SDP (service tunnel) binding for services —if service CAC is not configured, bandwidth will not be considered by the NFM-P when selecting the tunnel.

Bandwidth availability for the tunnel is calculated at the service admission request time and is based on the links currently used by the tunnel forwarding path. The booking of reserved bandwidth by the service is done directly on the link and directly on the tunnel, for a bandwidth-reserved tunnel.

The link monitors the bandwidth used by all of the services using that link. Since the bandwidth reserved on each tunnel that is used by a service can be different, the link monitors bandwidth usage through the tunnels rather than through a service.

You can perform a system-wide audit to ensure that the bandwidth on each link is properly calculated. The audit visits all tunnels in the network and adjusts the available bandwidth in all links currently being used by the forwarding tunnel path. The adjustments are made based on total bandwidth requests per CoS for all EVPLs currently using the tunnels.

You can perform this audit by clicking on the CAC Audit button on the Manage Services form, or by choosing CAC Audit on the More Actions button. The audit also occurs automatically on system startup and when service CAC is switched from disabled to enabled.