We will soon be deploying an IP telephony solution for a small company, which includes a voice gateway router w/ PSTN access. The PSTN connectivity will be provided by a T1 circuit, which has yet to be ordered. It's my understanding that a single T1 circuit will provide this company both local and long-distance (LD) PSTN connectivity.
We have other customers, I've noticed, that have multiple T1's, and they are broken down by type - "6 T1's, and 4 LD T1's", for instance. I'm trying to understand the specific differences between the two, functionally. My questions:
1) Is the difference really just a pricing decision, where local "regular" T1's provide free local calling and charge for LD, where an LD charges minimally for LD calls, and more for local? (So, a large organization that is expecting a lot of concurrent LD incoming or outgoing calls would justify purchasing LD circuits?)
2) There really would never be an absolute requirement to purchase a LD T1, since a local T1 can provide LD service (just at a higher cost), correct?
3) I've read that LD T1 circuits do not provide dial tone. Does this mean that only incoming calls can come in over a LD T1, and that all outgoing calls will always traverse a local T1?
Thanks, and any additional detail and supporting docs/links are always appreciated.