Thanks Pix,
As per u, this is not possible to avoide such request.If in a city there is only two operator say A and B. And if site of B Operator down for whole city around about 6-8 Hours. During That period, Will thers is large number of request on Network A and might this can cause network congestin for the A. If one imsi see that reauest fails to connect to network A and then after how much time the imsi again send the request. or is there any paramete in the MSC that can bu used at this situation to avoide these request or deilay the request to come again and again.