Default Burst in a LAN QoS Policy

A.

The default burst value in a LAN Quality of Service (QoS) policy depends on the platform and software version being used. However, there are some general guidelines that can be followed.

In general, the burst value determines the maximum amount of traffic that can be sent at once before the rate limiting feature is applied. Burst size is expressed in bytes. It is a critical parameter that determines the amount of traffic that can be forwarded before the rate limiting feature kicks in.

For example, if a QoS policy is configured to limit traffic to 100 Mbps, and the burst size is set to 10,000 bytes, then the maximum amount of data that can be sent before the rate limiting feature is applied is 100 Mbps * (10,000 bytes / 8 bits) = 125,000 bytes.

The default burst value for LAN QoS policies can vary depending on the platform and software version being used. However, some commonly used default burst values for Cisco devices are:

• 9216 bytes for Ethernet interfaces on Cisco Catalyst switches running IOS software
• 10240 bytes for FastEthernet interfaces on Cisco Catalyst switches running IOS software
• 20480 bytes for Gigabit Ethernet interfaces on Cisco Catalyst switches running IOS software
• 1548 bytes for ATM interfaces on Cisco routers running IOS software

It is important to note that these are just examples, and the actual default burst values may vary depending on the platform and software version being used. It is always a good practice to check the documentation or contact the vendor to confirm the default burst values for a specific platform and software version.