Replacing PRIs/Cornet with SIP trunking?

[lhiraman]

We currently have a HiPath 4000 v6 PBX with PRIs to handle our traffic inbound and outbound. We have two remote sites that are connected to us by cornets and their calls inbound and outbound routes via our 4000.

As a cost saving measure, can we replace the PRIs and cornets at each site and tie them together via the telco provider? Also how big of a change configuration would have to take place on our 4000 and the two 3800s that are out there?

THanks!

 

[donb01]

I don't know about the provider part because we don't have those services here yet, but how do you have your system configured - mostly IP (HFA), mostly SIP, digital?

If I understand this right, the same STMI card(s) that handle your phones also handle your trunks in this case, so you would need to have enough SIP capacity to cover the trunks configured on the boards. If you don't have enough SIP ports configured you would either need to add boards or reconfigure boards. To reconfigure the STMI board to change the allocation of SIP vs IP requires you to delete all the stations off the board (or at the very lease change all their PENS so nothing is configured on the board.

One board can handle up to 120 ports, but I would not configure more than one PRI per board no matter how many open ports are on it from both a redundancy and traffic perspective. If you have more than one cabinet I would even try to spread them out across the cabinets.

License-wise the 4000 port licenses are good for anything so that shouldn't be an issue.

Being in healthcare I subscribe to the "christmas lights" analogy, and try to avoid a situation where if one goes out they all go out. I have 3 PRIs at the hospital - one comes in on copper and the other two on fiber, and I also keep my Cornet DS1s separate from the DS3 the IT people are using - I figure if that DS3 goes down we will lose all of our computer communication but more than likely still have the phones, and if one Cornet goes down the other 6 are still up and running - just a wee bit less stressful that way!

Hopefully there was something useful in there!

 

[lhiraman]

Don,

Your setup sound pretty simliar to what we have here. We have a hyrbid system here. Some IP and digital telephone, but everything routes inbound and outbound via the PRIs. The PRIs and Cornet are seperated from the regular Network Infrastrctue.

I entire point of all of this is to save money.

 

[donb01]

The vendors claim that I will be able to save money with SIP trunking as well "When it becomes available in our CO". I was the one who brought ISDN PRI to our CO by committing long-term to 7 circuits. They built it out for us and then were surprised when a lot of other people wanted it too.

I haven't seen any comparison numbers for SIP because they can't run a quote for this area yet - it will be interesting to see how it works out when it is available.