JDSU’s PVA-1000 VoIP Capture Agents reside across the network and collect detailed VoIP call statistics for signaling and voice transport quality. JDSU’s unique approach — providing unlimited remote agents at a bargain price of $8,000 to every user on the network — makes this package both flexible and scalable.
JDSU’s PVA-1000 VoIP Capture Agents reside across the network and collect detailed VoIP call statistics for signaling and voice-transport quality. JDSU’s unique approach — providing unlimited remote agents at a bargain price of $8,000 to every user on the network — makes this package both flexible and scalable.
JDSU’s agents — there even is a version that can be embedded with a user’s desktop for use with a softphone — capture bad VoIP calls as they happen. This information is combined with data about network jitter and packet loss and plugged into company’s PVA-1000 VoIP Analysis software.
JDSU offers great interoperability — the analysis software works with any agent that uses pcap (a common API for packet-capturing). In other words, you don’t need to use a JDSU agent or monitor to capture the traffic you wish to analyze with the PVA-1000.
In testing, it was quite apparent that JDSU’s roots are in the protocol-analysis market. Drilling down through the displayed alerts, you quickly land on screens full of the protocol statistics and packet decodes that you would expect to see from a protocol analyzer.
We found the PVA-1000’s interfaces and navigability to be extremely effective. The context-sensitive online help was excellent
Signaling trace diagrams for SIP, MGCP or Network-based Call Signaling (NCS), and SCCP are displayed clearly and in real time on the main interface as specific calls are selected from the continuously updating interface. By clicking on a message in the signaling ladder-diagram, the troubleshooter can obtain full protocol decode for Cisco SCCP, SIP, H.323, MGCP or NCS, Megaco, H.248, and RTP or RTCP.
The PVA-1000 identifies and evaluates every VoIP call by using a capture file, a process that then allows IT personnel to select individual calls for analysis. Each call can be scrutinized for signaling, jitter and packet loss. Additionally, the software can identify the RTP stream without the presence of signaling, if only a portion of a call is available in the capture file. The system works using a round-robin revolving capture-buffer, always capturing, just in case you want to trigger a capture and catch what already happened.
Being able to go into a huge capture buffer — to find the call you are looking for and then decide which component you wish to analyze — is an extremely impressive feature. The product also assists in finding exactly what you are looking for by providing a link from the GUI, finding the call either in its actual location or finding a portion of the call in the capture buffer. It’s like being able to find a needle in a haystack.
The PVA-1000 nailed all 24 network problems we set out for the test systems to discover. It doesn’t provide advice or recommendations on what to do once a fault is identified, however, which competing products do offer.
The PVA-1000 was very accurate in measuring real-time voice quality and network conditions. It was able to isolate and report on specific calls and automatically isolate and report on calls it found with voice quality below acceptable thresholds.
JDSU’s product offered great voice-quality statistics, including one the company refers to as “recency,” a measure of how close to the end of a call an event came that may have affected voice quality. This metric helps isolate faults in troubleshooting by providing the most relative (by time) network problem as it pertains to the call.
The PVA-1000 provides stereo playback with jitter buffer-emulation that allows replay of entire conversations, not just one side of a conversation, in duplex mode for better troubleshooting analysis. Buffer emulation lets the administrator “experiment” with different jitter buffer settings when replaying traffic, to test and prove configuration modifications on a small scale before applying the changes globally. The PVA-1000 also allows for easy translation of the VoIP capture files, for all or portions of a call, to WAV files for additional troubleshooting ability.
The PVA-1000 can be set to trigger and capture on a MOS threshold, and it will do this monitoring work transparently to the user. It did a good job of issuing alerts in real time when there were problems that needed attention.
The program creates sharp-looking graphical reports and pie and bar charts. Just about any point of interest is extensible and chartable to your liking, and data can be filtered and exported from the tool in a multitude of formats.
The distribution of problems throughout an individual call can be displayed on graphs, and the software provides moving audio-playback indicators that help show how the problems impaired audio quality. Summary-detail reports, fully formatted and ready for printing or saving in a number of formats, can be made for any capture file.
