The landline phone may seem an anachronism to many, but if like me you work from home it can still be an essential business tool. Even if you’re not a regular home worker, many people still like to have a phone that’s separate to their mobile. In a family house or shared house, it can sometimes also be useful for different people to have their own number too.

In the past, your choices were fairly stark—either multiple analogue phone lines, which is what I had when I first moved into my flat, or ISDN. While the latter was very popular in parts of Europe, it never really took off in the UK or US. BT’s pricing was part of the problem, together with a lack of equipment. Nevertheless, for many years, I used a small German ISDN PBX at home. It made it simple to separate business and work calls, and thanks to the 10 number blocks BT issued as standard with ISDN2 lines, my lodger could have a number too.

Pricing was the killer for ISDN in the home, unless you could claim it as a business expense. Now, however, VoIP services make it much easier to provide the same sort of functionality at a fraction of the cost, and it’s much easier than you might have thought, too. Here’s how I did it.