Subscriber Services: Adjust shaping rate & overhead accounting attributes based on PPPoE access line parameters

Extends the functionality available in earlier Junos OS releases to enable you to configure the router to use the Actual-Data-Rate-Downstream [26-130] and Access-Loop-Encapsulation [26-144] DSL Forum vendor-specific attributes (VSAs) found in PPPoE Active Discovery Initiation (PADI) and PPPoE Active Discovery Request (PADR) control packets to adjust the shaping-rate and overhead-accounting class of service (CoS) attributes, respectively, for dynamic agent circuit identifier (ACI) interface sets. In earlier Junos OS releases, you used this feature to adjust the shaping-rate and overhead-accounting attributes only for dynamic subscriber interfaces not associated with ACI interface sets. The shaping-rate attribute is based on the value of the Actual-Data-Rate-Downstream VSA. The overhead-accounting attribute is based on the value of the Access-Loop-Encapsulation VSA, and specifies whether the access loop uses Ethernet (frame mode) or ATM (cell mode) encapsulation. In subscriber access networks where the router passes downstream ATM traffic to Ethernet interfaces, the different Layer 2 encapsulations between the router and the PPPoE Intermediate Agent on the digital subscriber line access multiplexer (DSLAM) make managing the bandwidth of downstream ATM traffic difficult. Using the Access-Loop-Encapsulation VSA to shape traffic based on frames or cells enables the router to adjust the shaping-rate and overhead-accounting attributes in order to apply the correct downstream rate for the subscriber.