3Com Baseline Switch 2924-PWR Plus review
3Com’s new Baseline ethernet switches have a keen focus on small businesses with limited IT support that want a well-featured, managed switch that’s easy to implement. The 2924-PWR Plus aims to meet these needs and is designed to operate straight from the box (as long as you like its default settings).
This Layer 2 switch has an eye on VoIP applications and offers a number of features aimed at automating deployment of IP phones and prioritising their traffic. It also brings PoE to the table, as all two dozen of its standard gigabit ports are 802.3af compliant. Initial installation is swift, since the switch is set to take a management IP address from a DHCP server. The browser interface opens with a tidy graphic of the switch where each port is colour coded, so you can see at a glance what’s connected to it and its status. These also show whether power is being provided, and PoE settings can be configured from the web interface. PoE can be enabled or disabled on each port, and the lower the port number the higher its power priority. You can also override these and guarantee power to selected ports, but with a maximum of only 180W to play with you may not be able to use all ports for supplying power.
The default settings may be fine for general network usage, but there’s some work to be done before you can use the automated VoIP functions. Your first task is to create a new VLAN to be used specifically for voice operations. Next, you activate a voice VLAN, assign the new VLAN to it and select the member ports. If you opt for the manual port mode, the switch will prioritise traffic for any device attached to the member ports. When set to automatic, a port will be placed in the voice VLAN only if an IP phone is connected to it and recognised. The switch tries to identify the phone from its OUI (organisationally unique identifier), which is the first 24 bits of its MAC address. 3Com includes the OUIs for seven vendors including itself, Cisco and Siemens, and we were able to add Linksys to the list as we tested using its SPA921 business IP phone.
With the Linksys phone connected to the switch, a glance at the voice VLAN status screen showed the port had been dynamically added as a member. All traffic for the phone will now be given top priority, with only switch management packets getting better treatment. We then powered the phone off and the switch automatically removed it from the voice VLAN.
Port security is another useful feature of the Auto mode. Packets arriving on member ports that have an unknown MAC address will be dropped. We discussed some of the features with 3Com’s helpful technical support, and were pleased to discover that it’s now in-house.
The 2924-PWR offers a fine range of features at a very affordable price. It isn’t as easy to install as 3Com makes out, but the automatic recognition and dynamic VLAN assignment for IP phones could prove very useful.