Notes for others reading this thread:
- RBOC stands for Regional Bell Operating Company. In this case it means "the local telephone company."
- T1 lines are digital circuits which provide 1.544Mb/s of bandwidth.
- T3 lines are digital circuits which provide 44.736Mb/s of bandwidth.
- "Local loop" is a term used to describe the portion of the phone network which connects the customer to the Central Office (CO). It is also colloquially known as "the last mile."
Now, on with the discussion.
The best way of avoiding local loop charges is to get off the local loop -- by going wireless.
I don't know how your company's office and network are currently designed, so I will describe a fairly average situation.
If you currently have your T1 and T3 lines split into data and voice lines, one of the first things I would do is switch to
VoIP so that all lines can be made into data lines.
Then, I would network my buildings together using wireless gear. I would most likely use
Othogon Wireless OS Gemini 5.8Ghz Wireless Ethernet Bridges. I would do this because they offer T3 bandwidth and have excellent non-line-of-sight performance.
Finally, I would place one more wireless connection -- on site at my ISP's POP (Point of Presence).
All voice and data traffic would travel over the wireless data links directly to my ISP. From there, the VoIP traffic would be routed to my VoIP provider. I would save money both by avoiding local loop and by avoiding the
PSTN altogether.