Cisco SRW224G4P User Guide - Page 57

24-Port 10/100 + 2-Port Gigabit Switch with Webview and Power over Ethernet Rate Limit This function allows the network manager to control the maximum rate for traffic transmitted or received on an interface. Rate limiting is configured on interfaces at the edge of a network to limit traffic coming out of the switch. Traffic that falls within the rate limit is transmitted, while packets that exceed the acceptable amount of traffic are dropped. Rate limiting can be applied to individual ports or lags. When an interface is configured with this feature, the traffic rate will be monitored by the hardware to verify conformity. Non-conforming traffic is dropped, conforming traffic is forwarded without any changes. The rate limit screen displays both Fast Ethernet Granularity and Gigabit Granularity. Rate limit granularity is an additional feature enabling the network manager greater control over traffic on the network. The "rate limit granularity" is multiplied by the "rate limit level" to set the actual rate limit for an interface. Granularity is a global setting that applies to Fast Ethernet or Gigabit Ethernet interfaces. Use the drop-down menus to change the rate limit for fast ethernet and/or gigabit granularity, click submit. Set the Input Rate Limit Status or Output Rate Limit Status, then set the rate limit for the individual interfaces, and click Apply. To configure input rate limit for each port or lag, click Port Conf or Trunk Conf in the Input row of the table respectively. To configure output rate limit for each port or lag, click Port Conf or Trunk Conf in the Output row of the table respectively. Rate Limit Configuration To configure Port Input Rate Limit, click the Enable checkbox and then set the rate limit level in the textfield provided. Port Rate Output Limit is configured the same way on the Port Output Rate Limit Configuration screen. If a port is assigned as a lag member then the rate limit of that port cannot be set in the port configuration screen. Truck Rate Limit is configured the same way as port rate limit using the trunk Input and output screens. Chapter 5: Configuring the Switch through the Web Utility QoS Figure 5-31: QoS - Rate Limit NOTE: When the rate limit granularity is set to a low value (for 10/100 ports, less than 512 Kbps), the maximum bandwidth available on ports is restricted to a value that is "256 x granularity." This restriction also applies to ports with rate limiting disabled. 49