Exam 300-415 topic 1 question 385 discussion

It looks that with AAR it is different from the default BFD multiplier by normal SDWAN tunnel ... The BFD default values in Cisco SD-WAN are hello-interval 1000msec, multiplier 7, and dscp value of 48 https://ccieme.wordpress.com/2021/02/08/sd-wan-application-aware-routing/ https://www.networkacademy.io/ccie-enterprise/sdwan/application-aware-routing-app-route-policy

correct A

https://www.cisco.com/c/en/us/td/docs/routers/sdwan/command/iosxe/qualified-cli-command-reference-guide/m-bfd-commands.html

To determine the SLA classification of a tunnel, application-aware routing uses the loss, latency, and jitter information from the latest poll intervals. The number of poll intervals used is determined by a multiplier. By default, the multiplier is 6, so the information from all the poll intervals (specifically, from the last six poll intervals) is used to determine the classification. Reference: https://www.cisco.com/c/en/us/td/docs/routers/sdwan/configuration/policies/ios-xe-17/policies-book-xe/application-aware-routing.html

The Multiplier value determines how many consecutive BFD probes must be lost before a vEdge router declares a tunnel as down, as illustrated in figure 3 below. The BFD default values in Cisco SD-WAN are hello-interval 1000msec, multiplier 7, and dscp value of 48 . https://www.networkacademy.io/ccie-enterprise/sdwan/application-aware-routing-app-route-policy#:~:text=The%20Multiplier%20value%20determines%20how,illustrated%20in%20figure%203%20below.&text=The%20BFD%20default%20values%20in,and%20dscp%20value%20of%2048%20.

correct answer is B

A. 6 The BFD multiplier in application-aware routing is a user-configurable parameter that determines the time to calculate mean loss, mean latency, and mean jitter. This value multiplies the polling interval to specify the time for these calculations. The default value for the BFD multiplier in application-aware routing is 6.

B correct