The Feasibility of the requested Leased Circuit depends upon the availability of PCM Channels between the 'A' end & 'B' end exchanges, the local cable leads from 'A' end to its local exchange and from 'B' end to its local exchange. In general, the PCM channel is most important, and is being obtained from the Transmission unit of MTNL.

In case of National circuit, the feasibility involves three components :
a) Mumbai end
b) Distant end
c) Between Mumbai and the distant end.
Feasibility for 'a' will be obtained from Transmission end, that of 'b' will be obtained
from distant end and 'c' from Western Telecom Region.