How to Troubleshoot Problems with SIP Trunking

SIP trunking is one of the most cost-effective and efficient applications of cloud communications available today.  But, despite its advantages, some of our customers have questions about the potential problems with SIP trunking they might encounter.

In this guide, we’ll discuss some of the most common issues that users face when adopting a SIP trunking solution and share our best troubleshooting tips.

3 Common Problems with SIP Trunking

Although every cloud communications setup is unique, there are some potential challenges with SIP trunking that most businesses will need to address.

Porting Your Existing Numbers

One of the best things about SIP trunking is that it allows you to use your existing assets, including your current phone system and telephone numbers.  But, sometimes it can take a little while to port your telephone numbers.

In most cases, outgoing carriers and your new SIP trunk provider can collaborate to transfer your phone numbers in 2 weeks, and sometimes more quickly than that.  But, keep in mind that when you move your numbers, your carrier loses revenue, so they may not be in as much of a hurry as you are.

We recommend working closely with both your carrier and your SIP trunk provider to expedite the process of porting your numbers.

Configuring your phone system for simultaneous calls

When you choose to implement a SIP trunking solution, you’ll want to assess how many simultaneous calls the system needs to be able to support.  The best way to calculate this number is to determine how many concurrent calls occur during your peak hours.  (This should include both incoming and outgoing calls, as well as callers on hold.)  For each simultaneous call path, you will need a SIP trunk channel.

If you over or underestimate how many simultaneous call paths you need to support, don’t worry.  Well-equipped providers can easily add or remove SIP trunks as needed.

Choppy or lagged calls

The quality of Session Initiation Protocol (SIP) and Voice over Internet Protocol (VoIP) calls are almost entirely dependent on the quality of your Internet connection.  If you’re experiencing choppy or lagged calls with your new SIP trunking service, you may not have adequate bandwidth to support the increased volume of call traffic.

Not sure how much bandwidth you need for high quality SIP calls?  No problem!  You don’t have to know all of the technical details, but you will need to know which codec you are using, and how much bandwidth that codec consumes per call.

The term “codec” is short for “encoder-decoder,” which is the mechanism that converts audio signals into digital form so that they can be routed over the Internet.  Most SIP trunking provider use the G.711 codec, which requires around 85 kbps of bandwidth per call.

Once you know how many simultaneous calls you need to support and how much bandwidth each call requires, you’ll just do a little bit of math:

# of Simultaneous Calls x 85 kbps per call = Required Bandwidth

If you have adequate bandwidth and you’re still experiencing poor call quality, you may need to adjust your Quality of Service (QoS) settings.  QoS allows you to prioritize particular types of data, such as voice packets, on your network.  Other forms of data are not always time sensitive, so you can alter your QoS settings to prioritize voice traffic.

Solving Problems with SIP Trunking

By working closely with your provider and configuring your communications infrastructure correctly, you can easily solve any problems that you might encounter with SIP trunking.  And know that you know some of the potential challenges of adopting a SIP trunk solution, you can even prevent them!

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