Applying a Shaping Rate to Physical Interfaces Overview
On T4000 routers with Type 5 FPCs and on EX Series switches, you can configure physical interfaces to shape traffic based on the rate-limited bandwidth of the total interface bandwidth. This allows you to shape the output of the physical interface, so that the interface transmits less traffic than it is physically capable of carrying.
If you do not configure a shaping rate on the physical interface, the default physical interface bandwidth is based on the channel bandwidth and the time slot allocation.
In general, the physical interface speed is the basis for calculating the various queue parameters for a physical interface such as delay buffer size, weighted round- robin (WRR) weight, drop profile, and so forth. However, when you apply a shaping rate by including the shaping-rate statement, the shaping rate on that physical interface becomes the basis for calculating all the queue parameters for that physical interface.
On T4000 routers with Type 5 FPCs, the shaping rate value for the physical interface must be a minimum of 292 Kbps. The maximum value of shaping rate is limited by the maximum transmission rate of the interface.