On 21/Mar/18 19:10, Jason Lixfeld wrote:
A few years ago I did some testing and found that the time between the transceiver detecting LOS and the routing protocol (ISIS in this case) being informed that the link was down (triggering the recalculation) took longer than it took BFD to signal ISIS to recalculate.
You also have the issues of: * Deciding whether you want to have a uniform standard when deploying BFD. If your standard is not to on dark links and should do lit links, you can quickly run into an administrative scenario as your network grows, and keeping track of which link is what re: BFD or not can be someone's untangling project 10 years later. * Circuit providers delivering hybrid links and not telling you because they are either afraid to or don't fully understand the scope of their (very large) network. In this case, you're told the link is dark, but somewhere along the path is their active gear. (not so) Strange, but true. Mark.