Set Up Rate Scaling

A rate policy can be configured to scale guaranteed and excess bandwidth allocation for low-speed and high-speed connections. PacketWise detects the speed of an incoming flow and uses the policy's low-speed and high-speed rate settings to scale a minimum rate for the connection.

When PacketWise examines a flow, it can discriminate between a client with a modem connection and a client with a higher-speed connection. The rate given to the client is based on a sliding scale, which is dependent on the client's speed. PacketWise monitors the speed throughout the life of a connection and adjusts bandwidth allocation as the effective connection speed changes.

Take, for example, a class that has a rate policy with guaranteed rate settings of:
Low-speed = 10 Kbps; High-speed = 30 Kbps. In this example, a slower client would be guaranteed a rate value on the low end (perhaps 15 Kbps) and a faster client would be guaranteed a rate on the high end (perhaps 25 Kbps). Excess rate is distributed with a similar scaling factor, with slower clients receiving a smaller amount than high-speed clients.

This advanced tuning feature is rarely used, as PacketWise automatically determines optimum bandwidth-allocation. However, if you have applications that require more precise control, use this feature to pace excess bandwidth allocation.

Note: To perform this task from PolicyCenter, you must first select a group and/or unit configuration from the Group: and Unit: drop-down lists at the top of the page.

To set up rate scaling for a rate policy:

1. Open the rate policy you want to modify. (SeeModify a Policy.)

2. Click scaling in the Policy window. The Policy:Scaling window opens.  show screen

3. Choose Explicit for the Excess Rate to enable rate scaling.

4. In the Low text box, enter the desired rate for this class' low-speed connections. (The minimum value allowed for the low-speed excess rate setting is 256 bps.) Rates may be specified as integer bits per second, followed by a “k” (thousands) or “M” (millions).

5. In the High text box, enter the desired rate for this class' high-speed connections.

6. In the Limit text box, enter the maximum excess rate that can be used by this class' low-speed and high-speed connections.

7. Click OK.

8. Click apply changes in the Policy window.

See also:

Set Up Web Redirection