I am running MLPPP throughout my WAN. Most recently I installed a 3845 and I had to turn MLPPP fragmentation off in order to get the circuits to stop dropping packets. I am have read multiple articles on MLPPP fragementation and still do not understand why this would cause a problem. I am experiencing lost fragments and I am thinking that the cause of this may be that the circuits in the bundle have difference latency-prehaps for diversity and this is causing a problem when fragmentation is enabled. I have 50 other sites where fragmentation is enable and they are running fine. Can anyone explain why fragmentation would cause this kind of problem? From the show ppp multilink command, I am seeing lost fragments and discarded fragments. When I experienced the problem aforementioned, I opened a TAC case but the engineer could not explain why the fragmentation would cause this problem, so I'm reaching out to the Cisco IT community for more indepth information.