Wdym by backend? If you mean backbone then it's Tata.Btw which backend excitel uses ??
can you elaborate how do you check it ,Lack of port forwarding and less performance. The LCO could also share that single account with others as well.
The LCO will likely setup a router in the middle to serve you the internet without officially registering with Excitel.
I noticed my LCO do the same while port scanning.