Hi
I am asking this question because there are so many different information about in which layer frame relay and adsl operate.
I was sure that Frame Relay operates just in Layer - 2, has nothing to do with Layer - 1. But some web pages say that FR operates both Layer - 2 and Layer - 1.
Also I was sure that ADSL is a Layer - 1 technology, has nothing to do with Layer - 2. Also, End-to-End ADSL Architectures book says that:
"Like analog modems, cable modems, wireless, and T1 lines, DSL by itself is a transmission technology, not a complete end-to-end solution. End users don't buy DSL. They buy services such as high-speed Internet access, an intranet, a leased line, voice over DSL, a virtual private network (VPN), and video on demand (VoD)."
But some web pages say that ADSL is layer - 2 technology.
So my questions are:
1-) Can you please tell me in which layer do Frame Relay and ADSL are?
2-) If I am right, that FR is just Layer-2 protocol and ADSL is Layer - 1. So Frame relay wan connection can communicate over ADSL. Right?