White Paper on Inter-Tel IP Telephony by BTI Communications Group

Voice transport over the Public Internet

Applications:

Branch Office to Distant Branch Office

Make calls using a standard telephone and a centralized Internet connection, with the Internet substituting for the Public Switched Telephone Network (PSTN).

Accomplished via Internet gateway servers.

Connect a PBX to the Internet through one connection, allowing any user of that PBX to make calls over the Internet.

To place a call, the caller would dial the number of the party they are calling, just like making a call through the PSTN. The PBX would then route the call through the Internet gateway via a programmed trunk interface and the gateway would contact another gateway at the called site.

Site-to-Site Long Distance Call

Branch Office to Distant Phone User

Calls can be routed through the trunk lines of a remote PBX to reach another user in the same area.

Caller in one city to place a call over the Internet to a distant city, avoiding long distance phone charges.

To place a call, the caller would dial up an Internet gateway server in the destination city. When the call arrives at the PBX in the destination city, the PBX would transfer the call to an outbound trunk and dial the caller's desired number. Since the call is being made from a PBX in the destination city, the call would be recognized as a local call and no long distance charges would be accrued.

Outgoing Call Through Remote PBX

PC to Phone User

Tie together the desktop Internet Telephony software with the power of the Internet gateways and gateway networks.

To make a call through the gateway network from a desktop Internet Telephony program, a user would dial up the IP address of an Internet gateway server. The call would then be routed over the Internet to the Internet gateway server, and then routed to a PBX. From the PBX, the call can either be transferred to a telephone connected to the PBX or transferred to an outbound trunk to a make local call.

Desktop Software to Remote PBX

Fax to Distant Fax

Sending faxes to long distance numbers across the Internet is a feature that could save businesses, specifically international businesses, a great deal of money.

Faxing is not time/latency sensitive, like voice.

Industry experts estimate that faxes constitute up to 50 percent of all International calls.

The average Fortune 500 company spends $14 million annually on faxed transmission, 55% is intra-company faxing.

A fax device would attached to the PBX and fax calls routed to the Internet gateway server, where they would be captured and packetized as data. These digitized faxes would then be routed over the Internet to the destination gateway server and regenerated as a local fax call.

Sending a Fax Over the Internet Gateway Network