I have several location setup with PRI’s and DID’s

Is there any advantage/disadvantage to going to SIP? Maybe I don’t fully understand the differences in how they operate.

Any advice appreciated.

PRI is basically a T1. The full capacity of the PRI is 23 voice channels and 1 control channel. This is a dedicated connection from your switch to a telco switch and the PSTN. Out PRI costs about $700.00/month. A little over $30.00 a voice channel/month. This includes our DID’s. From our standpoint, SIP is not really that much expensive than PRI. I believe FreePBX has SIP trunks available for $25.00/month plus $1.00/month for DIDS

SIP uses the internet. From your switch, you go via internet to the switch of your provider, then on to the PSTN.

Because a PRI uses a dedicated circuit back to the PSTN, the reliability and quality will be better.

If you need to have as many as 23 voice channels/month, the best bet is PRI.

But…If you need only a few Trunks, SIP has the potential to save some money.


There are both advantages and disadvantages.

Most often it comes down to SIP allowing much better cost savings over PRIs but that can be very dependent on the local market you are in. Other advantages really depend on your PRI offerings and how they compare to the much broader base and set of features that SIP offerings may provide.

The one caution, if you go SIP you really want to make sure you go with a reputable offering such as what we offer with SIPSTATION™ or other services such as may offer. There are a lot to choose from and the quality, service, reliability, etc. will vary across the board.

Well said, Philippe. One thing I neglected to say is that we signed a 5 year contract.


No way to do DID’s with SIP though, right?

you can do DIDs with SIP no problem.

In fact, one of the advantages of SIP over many PRI providers is that you can get DIDs form any areacode and even international. Many PRI providers limit you to your local area for DIDs.