A small yet successful UK distributor of broadband routers and VoIP equipment, Solwise sent in a Billion 7100SV for this group test; a low cost VoIP-enabled router which can be used by home users and small businesses to access a range of SIP services.

The router itself is compact and well built, shipping with an AC adapter and all the cables needed in the box. That includes a patch lead to connect the router to the local network - via the single Ethernet port on the back - and another to connect to the ADSL line. A third port then accommodates the telephone via a small adapter that can be used use with any standard UK handset.

Getting started with the Billion 7100SV is relatively straightforward, with a browser interface that features a quick start page for the ADSL setup. It took us no more than a couple of minutes to type in our test account name and password and connect to the Internet. A built-in firewall then looks after the security side of things with the usual port mapping facilities plus support for UPnP and Dynamic DNS services, if required.

SIP setup is similarly straightforward and further simplified by pre-configured settings to use the popular FreeWorld Dialup SIP service. All we had to do was register through the Web site to get an account and an associated SIP number which we then typed into the router.

On the downside, the documentation could be better and the Billion hardware had to re-boot every time we made a configuration change, which was a bit annoying. Plus, although you can make calls to other SIP users via FreeWorld Dialup, the service provider doesn't offer wider PSTN connectivity. For that you have to subscribe to another SIP service and configure the router appropriately. Not impossible but it does require a little more technical know-how than the basic setup.

Once configured we were able to connect an ordinary phone to make and receive SIP calls. Call quality depends on the codec used (that's the VoIP software used to encode/decode voice traffic inside the router), but those provided seemed pretty good most of the time with no more noise or other disturbances than on a typical dial-up line.

The emergency failover to the PSTN line worked seamlessly when we powered off the router and, by dialling a special prefix, you can elect to make calls over the ordinary network rather than IP, if preferred. There's no built-in SIP server, as on the Intertex router also reviewed in this group test, so you're limited to a single handset. But for home users on a budget the Billion 7100SV ticks the right boxes at a very affordable price.