During investigations on sporadique SD fails a rate on our network, we barred a cell which was having such a problem. We still observed a high number of SD assignment transactions (more than 1000), all of them ended up as radio SDCCH fails.
Can someone explain this? i’ve always thought looking at the procedure for SD, there should be no TCH or SD assignment on the cell?
Mousto, ok for TCH, but the SDCCH is a bit of a mystery.
as far as i recall (but i might be wrong.. please confirm), the state “BARRED” is transmitted on the BCCH, so the MS would not even camp on this cell. Therefore you are right : a MS should not be able to even request for a connection.