Trusted Reviews may earn an affiliate commission when you purchase through links on our site. Learn More

Intertex SurfinBird IX68 ADSL Air GW2 Review

Key Specifications

  • Review Price: £209.15

VoIP is proving to be a popular application, with a number of home and small business routers now supporting the SIP protocol. However, the majority of products have one thing in common – they can only function as a SIP client, which means you need to set up a SIP account with a service provider.

The delightfully named SurfinBird routers from Swedish company Intertex are virtually unique as they are one of the first products to market that incorporate a SIP server. They enable you to make free calls to other internal and external SIP users and receive calls from external SIP users as well. This neatly overcomes one of the biggest problems we often encounter – the fact that few firewalls are SIP friendly and require ports opened permanently to allow two-way communications or may need access to a STUN server. We are seeing a number of routers providing a SIP ALG (application layer gateway) but the SPI/NAT firewall in the Surfinbird routers dynamically configures itself for SIP sessions so no extra configuration is necessary.

On review is the IX68 ADSL Air GW2, which amalgamates Intertex’s SIP server with an integral ADSL2+ modem and 802.11b/g wireless access point. It’s a compact, lightweight unit with plenty of status LEDs on the front panel along with a separate LED display which shows the current firewall setting. At the rear you have a standard quad of switched Fast Ethernet ports, a line port for the ADSL connection and a couple of ports for attaching PSTN handsets.

Initial installation is fairly straightforward, although it will take a little while to get used to the router’s web interface. The network configuration page opens with a bold graphic of the router’s rear panel where you select each interface and enter the relevant details. For direct ADSL connections you enter your ISP account details in the appropriate boxes and either leave the LAN ports at default or change the internal address and DHCP server range. The fourth LAN port supports multiple functions as it can act as a standard network port, a WAN port or as a separate network with its own DHCP server. For wireless services you merely activate the access point and select from WEP, WPA or WPA2 encryption. The IX68 also offers a closed mode which masks the SSID, a café mode that stop wireless users from seeing each other and a MAC address access list as well.

No doubt the most interesting feature is the SIP server and configuration is well documented with plenty of on-line manuals. If you use an external SIP service there’s nothing to do as the firewall is already configured to allow SIP communications through. Your first step for the SIP server is to assign a dynamic DNS address to the router’s WAN port and for this we set up an account with Next, you need to enter your domain name in the router’s SIP Settings page and decide how you want to control incoming and outgoing calls. Note that the price only includes five SIP user licenses but you can purchase more from Intertex.

At this stage you’re ready to go and can use pretty much any SIP client on the LAN. We successfully tested using a Linksys SPA921 IP telephone and Windows Messenger. For the latter you must upgrade to v5.1 and also apply a small registry fix to allow simultaneous support for .NET and SIP communications. You also need to set up SIP from the Accounts tab where you provide a sign-in name which can be anything as long as it’s followed by your domain name.

”’The simple home page gives away few clues as to the level of SIP features behind it.”’

Using a basic headset we found SIP calls between two Windows Messenger users to be extremely clear. In fact, we used this mode of communication to discuss the router’s more esoteric settings with Intertex support in Sweden. If you want more from your SIP services the Surfinbird routers also offer an optional SIP software switch upgrade, which enables an extensive range of PBX style functions such as simple extension numbers for easy internal dialing, incoming call mapping, custom dial plans and much more.

The Surfinbird also supports, as standard, outgoing calls from a SIP phone to a landline and incoming calls from a landline to a SIP client. You need to use the supplied cables and splitters to provide PSTN access on the ADSL line but with this in place LAN users can dial out to a landline by entering a prefix of your choosing. Inbound PSTN calls can be routed through to a SIP client on the LAN or either of the handsets attached to the line ports on the router. There’s more as you can enter a SIP URI from the router’s web interface and use one of the PSTN handsets to call it up.


The price may be comparatively high but the integral SIP server does add a lot of value to the SurfinBird routers. As you’d expect, configuration will take a while but there’s plenty of on-line documentation to help and the level of voice related features on offer from the IX68 is quite remarkable.

Intertex delivers a novel way of providing configuration access to all ports.


Basic SIP server configuration literally just requires your domain name to be entered.


The PSTN telephone ports offer a wealth of easily accessible call related features.


Windows Messenger 5.1 supports voice calls over SIP and we found call quality was remarkably good.


Trusted Score

Score in detail

  • Value 8
  • Features 9

Unlike other sites, we thoroughly test every product we review. We use industry standard tests in order to compare features properly. We’ll always tell you what we find. We never, ever accept money to review a product. Tell us what you think - send your emails to the Editor.