The VoIP management challenge
Enterprise network managers are implementing VoIP, but how are they managing these installations? Here are four tools to simplify the taskFollow @infoworld
OptiView is largely software-based, but Fluke allowed us to test the software using a dedicated hardware appliance, so installation was smoother. Our box was a 1U rack-mountable unit, though we kept it outside the rack during testing. We tested the new OptiView Protocol Expert Plus.
For those with their own workstations, OptiView runs on any NT, Windows 2000, or Windows XP Pro workstation. Network managers familiar with the OptiView interface and features will appreciate how well Fluke Networks integrated its VoIP tools with the existing OptiView software.
The Expert Plus version contains the same expert packet- and decode-analysis found in Protocol Expert, but also remotely monitors and even controls other Protocol Expert boxes and handheld OptiView Link Analyzers. Whereas this architecture isn't dedicated to distributed management capabilities (as in the Brix design), it does manage to mirror much of that functionality without a huge investment in new software and hardware.
It still offers all the usual goodies, including line rate traffic monitoring and traffic capture, packet decoding, Gigabit Ethernet support, and the usual series of network management metrics such as top talkers, VLAN analysis, utilization, and error rate.
Fluke Networks also adds its aptly named VoIP Option. This plug-in software for existing OptiView installations gives network managers many enterprise-oriented VoIP management tools.
With OptiView's history as a protocol analyzer, we expected support for a wide variety of VoIP protocols -- and we weren't disappointed. VoIP Option supports not only SIP, H.323, and Cisco SCCP, but also ASN.1, MGCP (Media Gateway Control Protocol), and SGCP (Simple Gateway Control Protocol). That's more than any other tool we reviewed.
The tool is heavy on QoS validation and measurement, too. It measures real-time QoS metrics for completed calls, initiated calls across most of its supported protocols, and even active calls.
It extends the QoS philosophy to other measurements as well, allowing users to set customer-defined "Quality Grades" for jitter, packet loss, r-factor, and setup time. These measurements can be served up numerically or graphically, presenting calls that measure up to the preset thresholds and those that do not.
In testing, we ran the OptiView a differently, as OptiView's engineer decided to plug the device into the switch port on the back of our Cisco 7960 VoIP phone instead of using a copper tap as we did with Acterna's device.
Under normal circumstances, the OptiView unit would be inserted into a network rack to monitor a SPAN's (switched port analyzer's) port. Indeed, Fluke Newtorks has a copper tap that looks suspiciously like a Net Optics unit, but our engineer didn't use one.
Unfortunately, because the port on the back of the 7960 is a switch not a hub, the OptiView couldn't see both sides of a conversation during monitoring, although it could play back the full conversation later.
After installation, however, the box gave almost exactly the same statistics as the Acterna DA-3400. The Fluke Networks unit did give us an actual MOS score, and the MOS scores were nearly identical to those measured by the
DA-3400, covering both RTP and RTCP to determine call quality by delay and jitter values of the packets themselves.