The Difference Between PSTN and ISDN

Before ISDN, businesses relied on Public Switched Telephone Network (PSTN) lines, the traditional copper phone lines familiar to most households across Ireland and most of the world. PSTN lines are analogue, meaning they transmit information as electrical waves, like how sound travels. This limits their capabilities – they can only carry one call at a time and aren't suitable for transmitting data efficiently.

ISDN, on the other hand, is a digital technology. It uses digital signals to transmit information, offering significant advantages over PSTN lines. An ISDN line can be divided into multiple channels, allowing for simultaneous voice calls, fax transmissions, and data transfers over a single line. This previously made ISDN an ideal choice for businesses that require reliable communication for voice calls, internet access and other data transmissions.

Is ISDN Still Used?

While ISDN is technically still relevant for the aforementioned reasons, its future is limited. While ISDN offered a significant leap forward in communication capabilities decades ago, newer technologies like Voice over Internet Protocol (VoIP) have emerged since with greater flexibility and cost-effectiveness.

Despite this, ISDN continues to be used in some specific scenarios. For example, businesses with legacy equipment like certain fax machines, credit card terminals, and security systems might rely on ISDN connectivity, requiring those businesses to maintain ISDN lines for continued operation. Some businesses might also use ISDN as a backup communication channel in case their primary VoIP connection experiences an outage. Overall, however, ISDN usage is declining and will soon near its end entirely.

Disadvantages of ISDN

While ISDN previously offered a significant improvement over traditional phone lines, it has its own set of drawbacks that contribute to its obsolescence.

Higher Costs

Compared to VoIP solutions, ISDN installation, service fees, and per-call charges can be more expensive. This makes it a poor choice to invest in now, especially with its phase-out on the horizon.

Limited Availability

ISDN services might not be readily available in all regions, especially remote areas.

Less Flexible

ISDN technology is also not as scalable as newer solutions. Adding more phone lines or data capacity often requires complex and costly upgrades, and the expensive maintenance of legacy communications technology is something that national telecom providers are attempting to progress from in favour of technologies like VoIP.

Outdated Technology

ISDN offers limited bandwidth compared to modern internet connections, restricting data transfer speeds.

Equipment Dependence

Certain functionalities of ISDN rely on specialised equipment that also might become difficult or expensive to maintain as the technology becomes phased out.

The ISDN Switch-Off

ISDN technology will be phased out sooner rather than later. Originally, it was announced that traditional ISDN lines would be switched off in 2025, but this has since been revised to a switch-off date of January 2027. The reasoning for the delay was so that there would be more time for the switch-off program to better protect more vulnerable customers such as the elderly and those with additional needs, like telecare users. Either way, the end of ISDN is approaching soon, and businesses need to prepare accordingly.

Preparing for the End of ISDN

With the ISDN phase-out coming in the near future, businesses need to take proactive steps to ensure a smooth transition.

Firstly, take inventory of your equipment. Identify all devices currently relying on ISDN connectivity, such as fax machines, security systems, and credit card terminals. Then, explore alternative solutions for any ISDN-dependent equipment your business may have. Check whether they be upgraded to work with newer technologies like VoIP, as this will become the primary technology utilised by national telecom providers once ISDN is deactivated.

Once you’ve determined your business’s course of action, create an internal timeline for the transition from ISDN to your new communication solution. This includes budgeting for any equipment upgrades or service changes. Lastly, inform employees, clients and vendors about the upcoming ISDN switch-off and any changes to communication methods, if necessary.

The move away from ISDN signifies the continuous evolution of communication technologies. By strategically planning for the transition, businesses can ensure seamless communications even after the ISDN curtain falls. Need to switch your business to a fast internet-based communications system? We’ve got you covered. See how your business could benefit with Vodafone’s Business Broadband or Business Mobile Broadband packages today.