In the market for switches? Take a gander at 3Com's new Baseline Switch 2900 Plus Family. These bad boys support Gigabit speeds and Power over Ethernet and sport features that help streamline VoIP deployment. At a street price of around $850 for the model we tested, cost-conscious IT groups don't have to sacrifice capabilities to stay within budget.
We tested the Baseline Switch 2924 PWR Plus model, which comes in a 1U rack-mountable form factor with 24 ports. Of particular interest to us is the auto-voice VLAN functionality. This feature is billed as able to detect VoIP devices, such as SIP phones, and auto-assign the port to which the phones connect to a VoIP-only VLAN. This allows switch administrator to not only keep data and voice traffic on separate broadcast domains, but also apply QoS settings to VoIP traffic more easily—that is, at the VLAN level.
We plugged in several Cisco 7941 IP phones and were initially disappointed. The phones were hanging out on the default VLAN instead of the VoIP VLAN we'd configured, so we did a little digging. The auto-voice VLAN feature works by observing the MAC addresses of connected devices. If the first three two-hex groupings of the MAC address (called the OID) match a predefined value in the management interface, then the device is identified as VoIP capable. This means that VoIP endpoints must be connected directly to the switch for the auto-voice VLAN feature to come into play. In our case, the OIDs of our particular phones were not among the predefined values on the switch, so they were not automatically assigned to the VoIP VLAN. Luckily it was simple to add OIDs through the Web management interface, so the problem was quickly resolved.
Despite this temporary setback, we're impressed with the possibilities inherent in the auto-voice VLAN feature. IT theoretically wouldn't have to worry about a VoIP phone being plugged into the wrong port at the user's end, for example, and audio quality issues with VoIP are the most painful and costly to resolve. Any feature that takes user error and QoS issues out of the equation is always welcome.