3Com – Network Jack review

four-into-one Ethernet connector
Photo of 3Com – Network Jack
£75.79 + VAT

There’s more to the 3Com Network Jack than the name implies. What it does is enable four network devices to be plugged into just one Ethernet connector, the idea being to let you add printers, Voice-over-IP phones and other network devices without the inconvenience and cost of extra cabling.

The hardware involved is straightforward. Indeed the Network Jack is, in essence, little more than an unmanaged Ethernet switch with four auto-negotiating 10/100Mbps ports. However it differs from other entry-level switches in that it’s little bigger than a cigarette pack with the four UTP sockets easily accessible at the front. It’s also got a clever RJ-45 jack on the back enabling the switch to be plugged directly into an existing wall socket. And more clever still is an aperture in the middle so that if the Network Jack is plugged into a 2-port socket, or combined data and phone socket, the second connector is still accessible.

A plastic wall-plate is provided to enable the Network Jack to be attached to the wall over an existing socket aperture. The standard wall-plate is for single port outlets only, but manufacturer-specific dual port plates are available as optional extras (details of supported manufacturers can be found on the 3Com website). You also get a short RJ-45 connector cable to handle awkward installations where the existing cable isn’t quite long enough to enable the Network Jack to be plugged in directly.

You’ll need a screwdriver to fit the Network jack, but it’s a lot easier than wiring in a new socket from scratch. The only real issue is the power supply, with two ways of supplying the current needed to drive the switch hardware. One is to use an external AC adapter (£14.08 ex. VAT) which works fine but requires a free power outlet close by and isn’t very elegant. The other is to use Power-over-Ethernet technology to deliver DC current to the Network Jack over spare wires in the UTP data cable. To this end the 3Com hardware supports the recently ratified IEEE 802.3af standard for Power-over-Ethernet, with a single-port power adapter available for £15.70 ex. VAT.

The alternative to the Network Jack is to either run more cables and fit extra sockets, which could cost hundreds of pounds, or use a free-standing Ethernet switch. Compared to the extra cabling it’s a lot cheaper and more convenient and will be of great interest to companies in serviced offices where structural changes are not allowed. On the downside it’s more expensive than a cheap standalone switch, but then the 3Com Network Jack is a much more elegant solution and, because it’s wall mounted, less vulnerable to damage, especially when set up to get its power over the LAN.

Company: 3Com

Contact: 01442 438000

Where an office LAN is starting to run low on wall ports the 3Com Network Jack is a quick and affordable alternative to laying in new cables and connectors. It's a little more expensive than a standalone hub/switch but a lot more elegant with it's convenient wall mounting plus support for Power over Ethernet, if required.