The Linksys BEFSX41 is sold as a broadband router with one WAN ethernet port and four switched LAN ethernet ports. It has the usual SOHO router features such as static IP/DHCP/PPPoE/PPTP, IP masquerading/NAT, port-forwarding, DynDNS and others. As an extra it also has IPSEC endpoint support and an optional dedicated DMZ port, which is not so common in its price class. All in all it mostly just works like most Linksys gear.

Looking at its hardware, it's quite powerful:

• Conexant CX82100 processor running at 168 MHz
• ADMtek ADM6996 six port switch
• 2 MB flash
• 8 MB flash

It's noteworthy that the CX82100 has two independent ethernet ports, but the BEFSX41 only connects the first one to the switch chip (ADM6996) leaving the second port unused. The five other ports of the ADM6996 are connected two the 5 external RJ45 jacks and thus initially belong to the same ethernet segment. The separation into WAN and LAN ports (and the optional DMZ port) is done by the firmware using the VLAN capabilities of the ADM6996 (most current SOHO routers use this method).

The device is running VxWorks (like many SOHO routers) so there is no chance to add any extensions. That is unless you completely replace the VxWorks by uClinux. :-)