Implementing SIP trunks can be challenging or it can be managed like any other process.
Implementing SIP trunks can be challenging or it can be managed like any other process. Then there's the risk that some customers fear putting all their voice traffic over IP. After implementation there's usually follow up work with the local Telco, and that isn't always the most enjoyable for customers to undertake.
In my prior post SIP Aid, I noted that establishing test trunks is essential to testing your network and readiness for SIP trunks. I also suggested managing implementations in stages and to avoid implementing everything at once. There are some basic moves customers can take to mitigate risk and when dealing with their local Telco or carrier.
One of our commercial accounts doubled the size of his office. After reviewing his telephone bill he asked what could he do to reduce it. We ported the published number and an 800 number. We retained three POTS lines (CustoPak--a Centrex service): two lines that hunt (rollover) and a third line for the fax.
We did this for a couple of reasons. The CustoPak lines are under contract and require a minimum of two lines. All the CustoPak lines have unlimited local and long distance calling included. We had the provider set the lead number of the two-line hunt group for accepting inbound traffic during any failover. In the PBX we set the outbound calls to always route over the two CustoPak lines first choice, to pack these lines with the most amount of traffic and to free up the SIP trunks for inbound and outbound dialing. Then, if a failure occurs, two simultaneous calls would route inbound. Last, we didn't breach the contract and the so customer doesn't need to face early termination liability from the Telco.
E-fax is another great way to push down the Telco costs. Inbound faxes route to the provider that delivers the fax to your designated email address(es). Outbound faxing is handled by our gateway on the IP-PBX and I've mentioned before that Panasonic has done an excellent job of fax over IP using SIP trunks using best route available via Internet, private line and MPLS. A key benefit to E-fax besides the lower costs is that simultaneous calls are possible, unlike many fax machines that are standalone or have limited hunt groups for inbound callers. Then, when a standalone machine runs out of toner or paper it may or may not queue inbound faxes, and when fax machines need rebooting, more disruption to inbound faxing occurs.
Several of our campus customers have learned that having an inventory and then physically verifying the inventory at the demarcation is important before beginning a transition over to SIP trunks. Fire, sprinkler and security alarms generally need POTS and we still see a lot of resistance moving these lines over to SIP trunks.
In every campus deployment, we've broken down the services that we are going to port in stages. While it takes longer, we seem to be more successful with both the provider and the Telco involved when transitioning services. We schedule an agreed-upon time to port, and it depends upon the comfort level of the customer and whether or not we anticipate issues. It's important to know the hours that your provider will provide support, including any other party involved in administering your network and telephony solution. Then, can you port at 12 noon or 12 midnight? Business needs often dictate an after-hours time, but assurances need to be set so that you have support when issues arise.
When customers deal with their carriers and local Telcos, we suggest that they do the same when cleaning up and disconnecting services--manage this in blocks. If you are going to disconnect lines under one account, then make that one transaction but don't mix accounts and tasks such as changing features or adding something. Hang up and call back and issue a separate request.
Whenever DIDs are involved in a SIP porting, do inventory and only port number blocks in groups at a time. When the porting becomes complex, too many things can go wrong that end up delaying the port or worse, losing the DID block. This is where it can get ugly, so customers need to pay attention to the fine print on providers' contracts about the loss of numbers and any recourse.
Another useful tidbit is to get to know your SIP trunk provider. One of our customers emailed us a string of emails from their provider. The provider's system automatically emails the customer contact whenever "All SIP Trunks are busy" at the customer end. How cool is this for a marketing tool? Really, it's effective. The client forgot to pull the trigger on adding more concurrent call sessions (SIP trunks). The provider's system automatically emails the client with the calling party's telephone number and date and time of the call(s). The provider that does this is Broadvox, and for anyone concerned about inbound traffic this is a meaningful tool.
A few weeks ago we ported a customer's services at 11:30 in the morning, we set programming changes the night before and outlined any changes during the porting. The provider called around 11:28 and asked if the port was still a go and around 11:32 we were off the phone and the customer noticed nothing. Don't you wish all ports were this easy? I remember what Sorell Slaymaker once said: "Complexity can be managed."