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.