CHAPTER 2 |
12
INSTALLATION AND CONFIGURATION
Example Option 2: Provider provisioned as generic SIP endpoints
From the Provider we order:
♦
A circuit to carry our phone traffic. This could be anything from a T1 to a 10 mbps fiber circuit. This is a dedicated circuit
that has IP addresses that are not routable from the public Internet.
♦
The carrier will usually provide a router or Integrated Access Device (IAD) at your studio site. The termination will be
an RJ-45 ended ethernet jack. The length of time needed to get this will vary wildly, depending on your location and the
provider that you’re dealing with.
♦
A small block of DID numbers for testing and later utility use.
From your distributor we order: (after a consultation with a Telos Applications Engineer)
♦
Telos VX Enterprise or Prime+ Engine
♦
Telos xNodes if necessary
♦
Quaified Network switch for L audio if not existing or too small
Here’s how it this all works in practice once installed:
♦
A listener dials 311 555-2300 (your studios number).
♦
That number is recognized by Telco and is connected to a (SIP) trunk to your facility.
♦
The telco connects to your PBX (off site) and sends the DID number to the PBX on the far end of the Trunk.
♦
Your provider’s PBX uses those digits to route the call further. (to the correct extension in most cases)
♦
The PBX rings the desired extension and causes ringback tone to be sent to the calling party until the called party answers.
♦
When the call is answered, a two-way audio path is cut through and the network is signaled that answer supervision
should be returned, charging the calling party of the call.
♦
When the call has ended, the stream is torn down and the customer billed.
If there was more than one appearance of the called extension on a particular phone (more line buttons), more calls could be
passed to that extension while in use. This would continue until no more channels were available, or an artificial limit in the
PBX, Trunk, or Telco would cause the “busy here” message to be sent back to the calling parties PBX or Central Office.
This means that:
1.
We can now build our own hunt groups
2.
We must consider the impact of getting more calls than we can handle.
3.
We can change the hunt group size on the fly in most cases.
4.
We must consider network engineering and security ramifications in design of the system because it’s delivered as IP.
Advantages: Fully protected from public Internet threats. Assured performance. It uses the most up to date technology.
Disadvantages: cost may be higher than Internet delivery
