<span class="font08 eg_up">Two exchangers of the same type, pass the connection of optic fibre, after a while (sometimes two or three days, one month) will appear obstructed network or throw the intersection of bag and phenomenon, pull out power of transceiver it inserts again again to be better sometimes. Change the transceiver, change other core of the optic fibre, change the line of jumping, won't do, please teach the experienced one! Thanks!</span>