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BT have announced they will be switching off their PSTN and ISDN lines in 2025 effectively turning off traditional phone lines and switching to faster, clearer IP technologies instead. This has played a big part in the increase in demand in VoIP. More companies are embracing an all-digital model, moving their communications to the cloud, making calls over the internet and embracing video conferencing.
We understand that some businesses are anxious that switching from ISDN to VoIP may cost them more money and hassle, but this couldn’t be further from the truth.
If you’re still unsure how migrating to VoIP benefits your business, this here’s an in-depth comparison of the two business phone systems to help you understand their differences.

What is ISDN?

ISDN or Integrated Services Digital Network is a circuit-switched telephone network system that transmits both data and voice over a digital line. You can also think of it as a set of communication standards to transmit data, voice, and signalling.

What are the benefits?

Compared to analogue PSTN calls, ISDN transmits higher-quality signals. Voice calls are of greater quality with reduced static, while the connection is more stable and has less disruptions.
Using an ISDN line, voice, video, data, and fax can all be transmitted over the same cable simultaneously, enabling multiple communication channels to be open at the same time, making it more efficient than older systems.

What’s wrong with this technology?

Installation and setup fees for ISDN cables can be costly, while having to pay for both the service and the cost of leasing the cables adds up quickly. Calls can also be more expensive than on newer internet-based telephony services.
The fact that ISDN phone systems are hardware-based makes ISDN difficult to set up and harder to upgrade because you’ll need to buy more equipment to provide the extra capacity you require. Because of this reliance on hardware, your ISDN system is vulnerable to equipment failure, which might result in network outage.
ISDN has been a reliable technology for companies since the 1980s but is outdated when compared to newer technologies. While ISDN provides quicker and more consistent transmission rates than its predecessors, it simply does not compare to broadband internet connection speeds

What is VoIP and why is it better?

Voice over Internet Protocol (VoIP) is a communications technology in which voice calls, as well as video and data, are transmitted over the internet, instead of ISDN. Rather than a physical PBX on the premises, most leading solutions have a Cloud-hosted PBX, and call switching is managed from here.
You can transmit faxes, host conference calls, forward calls from one location to another, use voicemail, have an auto attendant, and so much more, for a fraction of the cost. The fact that physical lines don’t need to be installed reduces the cost significantly. The system is plug and play and you can start using it almost immediately.
With a VoIP phone system, you won’t have to pay any monthly line rental fees. All the services you require are included in the amount you pay your provider, including audio and video calls, international calls, mobile app integration, and network management.
VoIP also eliminates the need for a separate voice network; all that is required is a high-speed broadband connection. It also gives staff access to a wide variety of apps and tools to help them maintain effective communication with co-workers even while working at home.
Let’s say some of your staff are working remotely, they can use 4G or Wi-Fi to connect to your system’s cloud PBX unlike older ISDN systems that could only operate on-site where your PBX resided.
Another advantage to VoIP is its scalability. Unlike ISDN solutions, which are hardware-based, cloud-hosted VoIP solutions are instantly scalable with minimal fuss. You won’t need to buy any more phone lines or cable modems since the cloud will provide you with enough space, allowing you to rapidly scale your business or increase your capacity.

So which should you choose?

Soon, it will no longer be a competition as PSTN and ISDN are being switched off in 2025. That means if you’re still using traditional phone lines, you’ll need to start preparing your VoIP transition now.
However, businesses should migrate to VoIP services not only because of the switch-off but because of the advantages they’ll be able to enjoy.
VoIP provides businesses with more flexibility than they’ve ever had before, ticking all the boxes by allowing users to be added through an online portal, connecting mobile phones to business lines, and encouraging seamless team collaboration.
Most of all, VoIP reduces the upfront and monthly costs businesses once had to shell out to have traditional phone lines.
Switching to VoIP gives you the opportunity to implement a unified communications strategy, with leading UCaaS (Unified Communication as a Service) platforms combining all your communications tools and platforms into a single interface for easy use.
If you’re looking to upgrade your business communications, we can help this smooth transition as we’re already helping lots of UK businesses transition from their legacy ISDN systems to our cloud-hosted phone system. If you need assistance, email us at [email protected] or give us a call on 03301227000.
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