07 Jan 2022

The internet has brought a whole new range of opportunities to businesses and individuals, but when it comes to telephony networks, people still have to rely on analogue phone lines. This is why some companies are moving their customers from ISDN to SIP. This guide will help you understand about ISDN & SIP what you need to do in order to switch ISDN to SIP in 5 easy steps.

Understanding the difference between ISDN & SIP

While the use of ISDN is relatively old, there are still a few people who have not used it. So what exactly is this technology? ISDN, or Integrated Services Digital Network, is an analogue technology that has been in use for telephone services. It provides a connection to the Internet through digital means. A single ISDN line can handle both voice and data traffic. If you are still using ISDN then consider ISDN to SIP migration. This is due to the fact that ISDN is scheduled to cease operation in December 2025.

Session Initiation Protocol (SIP) is an application layer control protocol that enables VoIP (Voice over Internet Protocol) services. It is an essential part of the protocols that enable communication between two or more parties using the Internet. SIP is also used to establish and maintain telephone calls, rather than making traditional analogue telephone calls over a physical line, though it is often applied to both types of calls.

How to Switch ISDN To SIP In 5 Steps?

Don't become a hostage to the old, analog telephone lines any longer. The fact that you made it this far means that you are already thinking about how to upgrade your business VoIP connectivity and not be held captive by traditional telephone infrastructure or telephony systems. You did a lot of research into various types of internet-based phone solutions before hitting upon one which best fits your needs; most people do just like yourself because they really want to get away from the old, slow and unreliable analogue phones.

This quick guide consisting of 5 steps will give you an overview of the process if you are considering ISDN to SIP migration:

1. Analyzing the job

Find out how the switch will affect your business by working with your communications provider. In a wholesale switch, the transition could take place in one move, or in phases through branches or even floors. As the switch combines SIP with ISDN, it eliminates the panic from switching from one system to another at the same time. A cost analysis is a part of this process as well. Your business should face very little disruption during this time. Moreover, you will have a controlled environment to conduct any tests or checks.

2. Examine the system currently in place

Auditing the customer's current infrastructure and network capacity will be an essential part of the process. This information is crucial for the provider in order to determine the best service provision needed for meeting business needs. It can also include assessing the available bandwidth on existing data connections to determine whether additional or dedicated connections are required to transport voice traffic. As with every audit, it will take several checks and double checks to make sure everything is going right.

3. Configuring the new system

Having determined the scope and budget for the project, the next step will be to begin the installation. Because SIP Trunking does not require as much physical infrastructure as ISDN, you will see a substantial difference in what needs to be kept in storage during ISDN to SIP migration. Additionally, since SIP can be used alongside ISDN during installation, there should be no significant disruption to your business systems during this time.

4. Performing tests and checking

As opposed to ISDN, a modern SIP-based phone system can integrate with a variety of business applications. These systems also feature resilience and business continuity. Before anything goes live, experts will check each of these components thoroughly to ensure the new system will work. During this time period, IT workers may find themselves busier than usual. Workers shouldn't notice a thing while your new system is being tested by your provider.

5. Go live

Let's get the new system up and running. The stage should not be as uncertain as it may sound, as all the checks have been done and continuity provisions are in place. You may be able to go live in one month, one day, or one hour depending on your original plan. Step five should go smoothly if steps one through four are working correctly.


The internet is transforming the way we do business, but it's not without its challenges. As this new era of technology evolves, so must our telecommunications networks. The growing popularity of SIP trunks is making it harder for businesses to maintain an ISDN infrastructure. Unfortunately, SIP trunks are replacing traditional ISDN telecommunication services that can handle more traffic than ever before. To switch ISDN to SIP, you'll need to make sure your existing phone system is compatible with SIP and then contact Wavetel to help you through the process.