Cable modems use a standard Ethernet interface, so a single modem can provide high-speed Internet access for several PCs on any home or office Ethernet local area network (LAN).
If the modem connects to the LAN through a simple Ethernet hub, an extra IP address must be purchased for each computer, typically at a cost of $5 to $10 per month, per address. What’s more, if the computers on the LAN are using Windows file- or printer-sharing features, linking the cable modem directly to a hub could pose a security risk. To address these issues, several companies have developed a new class of Internet-sharing devices (ISDs) that let several computers securely and cost-effectively share a single cable modem connection. Among the products in this category: Arescom’s EZ Rider Pro; Cayman Systems’ 2E; NexLand’s ISB2LAN; Ramp Networks’ WebRamp 700s; the UGate 3000 from UMAX Technologies; and ZyXEL’s Prestige 310. They start at $249 to $475 in their basic configurations.
Vendors tout these ISDs as plug-and-play networking devices, but they’re not for novice users. Basically, ISDs are Internet Protocol (IP) routers, offering firewalls and support for network address translation (NAT) and dynamic host configuration protocol (DHCP). To install an ISD, you’ll need a basic understanding of IP networking. Adding to the challenge, many cable modem service providers don’t formally support ISDs on their network, so it can take some effort to configure the devices for cable Internet access.
ISB2LAN
NexLand ISB2LAN
WebRamp700s
Ramp Networks WebRamp 700s
For users with enough technical sophistication to get an ISD up and running, there are key benefits. First, because the devices run NAT and DHCP, it’s not necessary to buy a separate IP address for each computer on your LAN. Instead, a single IP address is simply assigned to the ISD. Also, the ISDs offer firewall capabilities that prevent hackers from breaching your home or office network. For more information, visit: Arescom Cayman Systems NexLand UMAX RampNet ZyXEL For more cable modem product information, see: