forces is better than both ends to full duplex, autonegotiation can you have in a system of half-duplex half-duplex without collisions. in the worst case is that on one side you have half-duplex and full-duplex another which you would have collisions...
thanks krahmani323 Thanks for your comments, the problem was solved in this way.regardsRouter(config)#file privilege ? <0-15> Privilege level3 /**-*-*-*-*-*-*-*-**--*-*-*