Taking the leap, before the big switch off: ISDN to SIP

Taking the leap, before the big switch off: ISDN to SIP

You've probably heard about BT switching off all traditional phone lines in 2025. Why's this happening and what are the rewards? In this blog we answer questions that you want to know about taking the leap and switching from the legacy ISDN to SIP.

Quick reminder: What is ISDN?
ISDN is a legacy communications network that predominantly depends on physical infrastructure; in most cases, copper wiring to be specific. ISDN became the most popular and prominent network due to its voice and data transmission capabilities.
However, as it relied on physical infrastructure, it carries space and logistical issues. Not to mention, when things go south and break, there is often no quick fix to minimise downtime.

Who’s the new guy on the scene?
SIP. SIP stands for Session Initiation Protocol, which is an all-systems-go solution to replacing ISDN as it connects to business’s PBX via broadband, private circuit or ethernet.

In layman's terms: SIP is a type of communications network which utilises virtual lines (internet lines) to make calls between two or more people.

As you may know, ISDN2 is only available in pairs and therefore, if you only need 3, you’ll have to purchase 4. Also, if you’re stuck on ISDN30 and your business needs less than 8, you’ll be required to fork-out for a minimum of 8. SIP can provide from as little as 1 line, right up to and over 1000s of lines - providing flexibility and scalability benefits for your business.

What are the benefits of SIP

  • Minimise costs
  • One SIP channel can cost half of the ISDN equivalent, how? Connecting via IP costs less than ISDN line rental and calls cost significantly less to make.

  • Disaster recovery capability
  • ISDN lines can take days to repair and get back online, whereas SIP offers a much quicker resolution.

  • Growth and scalability
  • Offfering unmatched scalability benefits, with the ability to add lines seamlessly and cost-effectively.

  • Numbers and porting numbers
  • SIP isn’t geographically dependent so if you move premises you can keep the same number, even if you move across the country. UK numbers can easily be provisioned and ported.

  • Rapid deployment
  • SIP is quick and simple to setup compared to ISDN. Installation of an ISDN line is typically around six weeks, whereas a SIP Trunk can be installed in as little as 48 hours.

  • Be more flexible
  • Have the ability to relocate offices whilst keeping the same geographical number without costing a penny.

In conclusion, for future-ready businesses there no longer remains a viable reason to continue working alongside an ISDN network. The cost effectiveness, flexibility and reliability of SIP, provides businesses with an unmatched solution.

Need help taking the leap? We can help, get in touch with us today.