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So many applications and services are moving to the cloud these days.  One that we are seeing frequently is with our clients’ chosen PSTN providers. SIP has been around for 20 years now, but has been really getting traction in the last 5 years. It started when incumbent carriers, such as AT&T, decided to stop selling PRI services and only deliver SIP.  They might still give you a PRI hand-off for your phone system, but it’s delivered over SIP and converted to a PRI circuit at your location.   

The majority of our clients have made the shift to SIP services for dial-tone in some form, but now more and more of them are moving to cloud based calling. This sometimes requires them to change their existing SIP service. Generally, the best time to switch is when the existing SIP contract is set to terminate. If you have a few months left, you’re in a good position to change. If you have a couple of years left, it’s likely that the contract will have major penalties for leaving early, which is enough to make you think about waiting.  

When the time comes, how do you choose a SIP provider? Here are some things to consider:

Is Your Phone System On-Premise or Cloud-Based?

If you intend to keep an on-premise phone system, we recommend sticking with a local provider that can provide you a fiber based internet and SIP over the top service. This means they're terminating a fiber grade circuit to your facility, providing you bundled Internet and SIP service on the same circuit (or at least on the same fiber—some break it out as two separate circuits).   

If you decide to move to the cloud, you can consider cloud-based SIP providers instead. There are many to choose from, with a variety of features available.

Make Sure Your SIP Provider is Supported By Your Phone System

To choose the right SIP provider, you have to know which cloud-based phone system you are going with.

For example, Cisco Webex Calling supports specific cloud PSTN providers, but not all of them. Others rely on their own service, so you don’t have a choice of provider for your dial-tone. 

There is a strong argument for owning and maintaining control of your phone numbers and through a separate SIP provider instead of handing them over to the same company providing your phone system services. The reason is that it gives you flexibility in changing phone systems, and gives you leverage if needed. Your phone numbers are how your clients know to reach you, and should be considered intellectual property that you maintain control over.   

WebEx Calling has a feature called “Bring Your Own SIP Provider” that lets you to keep your existing carrier on-premise at your location. It just requires a voice gateway to make the connection between your existing provider and the WebEx Calling cloud.

Can Your SIP Provider Terminate Directly To Your Cloud Calling Provider?

As much as possible, you do not want your phone calls hairpinning back through your on-premise facility.

Hairpinning is when a user makes a phone call that goes out to the cloud calling provider over your internet connection, then the call is routed back to your facility over your internet connection to hit your local voice gateway, then the voice gateway routes the call back out over the internet again to your SIP provider. This creates a 2-3 second delay that can be very frustrating.

By choosing a SIP provider that can terminate directly to your cloud calling provider, you eliminate this problem.

Features & Pricing

SIP provider pricing ranges from $3-8/user, depending on selected features and also the size of the provider. Small SIP providers offer low prices but don’t have a robust infrastructure. Large SIP providers offer stability, low latency, and lots of features but at a higher price. There are also low-cost carriers who specialize in basic dial-tone with no other features.

Most providers offer unlimited plans for domestic calls. Knowing your usage will help you determine the best package for your needs. Do all of your users need unlimited calling? Some carriers allow you to pool your minutes together as another option.

Additional features to consider are things like:

• SMS (texting)

• Inbound faxing (yes, people still use this, surprisingly)

• Enhanced 911 capabilities

• DID or public number requirements

Each of these add a little more to the total cost.

Another option to consider is a cloud SIP provider with an on-premise phone system. This requires an investment in a voice gateway that can make the connection, but the the main decision is choosing a stable provider with the features you need. On-premise systems that don’t have current software generally cannot take advantage of some of the newer features available (like SMS), but most of our clients who choose this option do so strictly to reduce dial-tone costs, not to get more features.

Explore Your Options

Changing SIP providers is a cumbersome process that can take months to complete, and choosing a good provider can be tricky. It’s important to do your research so you don’t end up with a provider that doesn’t offer good service or is incompatible with your phone system. Taking your time to explore all the options and assess your needs will give your choice a greater chance of success.

If we can help you in any way, please feel free to reach out!