/mcpbandwidth 64 class data2 bandwidth 32 class class−default fair−queue ! interface Serial1/0 bandwidth 256 service−policy output llq In this example, any traffic that matches ACL 100 is classified as "class voip" (meaning voice traffic). It is given a high priority up to 32 kbps. ACL 100 matches the common UDP ports used by VoIP. Access−list 101 matches the H.323 signaling traffic (TCP port 1720). Class data1 matches web traffic (TCP port 80 as seen in Access List 102) and guarantees 64 kbps. Class data2 matches Telnet traffic (TCP port 23 as seen in ACL 103) and guarantees 32 kbps. The default class is configured to give an equal share of the remaining bandwidth to unclassified flows. The policy is called "llq". It is applied to outgoing traffic on Serial1/0, which has a total bandwidth of 256 kbps. Note: By default, the total guaranteed bandwidth and priority bandwidth for all classes needs to be less than 75 percent of the interface bandwidth. Modify this percentage by issuing the max−reserved bandwidth interface command. This table compares different software queuing mechanisms with their respective benefits and limitations. Software Queuing Mechanism Description Benefits Limitations First−In−First−Out (FIFO) Packets arrive and leave the queue in exactly the same order. Simple configuration and fast operation. No priority servicing or bandwidth guarantees possible.1 Weighted Fair Queuing (WFQ) A hashing algorithm that flows into separate queues where weights are used to determine how many packets are serviced at a time. You define weights by setting IP Precedence and DSCP values. Simple configuration. Default on links less than 2 Mbps. No priority servicing or bandwidth guarantees possible.1 Custom Queuing (CQ) Traffic is classified into multiple queues with configurable Has been available for a few years. It allows approximate No priority servicing is possible. Bandwidth guarantees are