The proliferation of VoIP testing tools is a positive indication of the
industry's maturity. In the past year, we've reviewed such tools from
companies like Digitech, Hammer, CC&T, Shunra, and Netrue. The latest
product is Surveyor 3.0, from Shomiti Systems.
The Surveyor 3.0 software, combined with Shomiti's laptop-sized
"Explorer" module, makes for a very powerful network analysis and
monitoring tool. Beside the traditional network testing tools, Shomiti
offers modules for remote access, traffic generation, expert analysis, and
Internet telephony QoS, all of which are Windows-based. The Explorer
interfaces range from 10Base-T to gigabit, and the unit includes a serial
port for VT-100 management.
INSTALLATION
Installing this product was relatively simple. Using our corporate LAN, we
installed the Surveyor software on a Windows 98 computer with a static IP
address. We used HyperTerminal to access the Explorer system for basic
network setup. For our operational testing, we worked with Microsoft
NetMeeting 3.0 -- not exactly creating enterprise-scale traffic, but it
worked fine for illustrating the Surveyor/Explorer feature sets. Once the
basic setup was complete, we installed the four plug-in modules, which are
called Remote, Packet Blaster, Expert, and Multi-QoS. The entire process
took about 30 minutes. (Although the product installation is painless,
learning and mastering the enormous feature set can take weeks. Our advice
is to be patient and tinker.)
DOCUMENTATION
There are four important documents for this product. The first is the
Surveyor Quick Start guide. This 18-page guide covers the basics like
installation, modules, and the primary system views. The basic function and
shortcut macros are also discussed here, along with information about where
to get more help. Next, there is the Explorer user's guide, which is a
30-page guide to the configuration and specifications of the Explorer
module. With its 250 pages, 13 chapters, five appendices, and a glossary,
the main Surveyor User Guide is the most important book. Lastly, there is
the online help, which is not context-sensitive and is mostly redundant to
the printed items.
Overall, we found the documentation to be quite helpful. Features are
explained without unnecessary complexity; there are plenty of screen
captures, tables, and illustrations, and most of the text is organized in a
manner that makes sense. The documentation for the QoS plug-in seems to be
more thorough than the documentation for the other plug-ins, but we received
good assistance from Shomiti's technical support team on a variety of
issues.
FEATURES
Although we examined the entire Surveyor application, we focused on the VoIP
aspects for this review. This meant spending some time with the Packet
Blaster plug-in, and spending the majority of our time with the Multi-QoS
plug-in. The Explorer analyzer modules (officially called "CMMs")
reside inside the standard Surveyor GUI. Each module has its own window,
labeled by IP address. (Double-clicking on a module reveals the detailed
views, discussed further in the Operational Testing
section below.)
Access to Surveyor's features is accomplished through the nine pull-down
menus, which are File, Configuration, View, Module, Remote, Host, Tools,
Window, and Help. There are also "Snoop" and "Sniffer"
modes, for viewing data with either the Surveyor modes or in the raw trace
mode.
Features of the Packet Blaster module include traffic generation and
packet capturing/editing. Packets are assigned by MAC address, and can be
generated from eight to 15,000 bytes long, with rates exceeding 100 percent
of the network speed. Configurations can be saved as templates, and users
can specify stream statistics such as frame rate, burst, and percent of
utilization, over all seven network layers. Beside saturation-type creation,
packets can be created individually, for precise network or application
troubleshooting.
The Multi-QoS features are equally powerful. Measurements can be made for
delay, jitter, buffering, packet loss, etc. The plug-in supports H.323, SIP,
MGCP, SGCP, and even Cisco's SSP. Also supported are RTP and RTCP, RAS, and
voice codecs like G.711, G.723, G.728, G.729, H.261, and H.263. The captured
data can be exported to a .CSV file, or it can be examined by call, channel,
or decoded packets. Users can also set thresholds, which spawn a system
alarm when the network or application conditions are unacceptable for VoIP
traffic.
OPERATIONAL TESTING
As we mentioned above, mastering this product can take months, and a monthly
deadline doesn't allow for such luxuries. So, we concentrated our tests on
the Multi-QoS plug-in, while measuring voice- and video-over-IP traffic
created with NetMeeting. We made several tests during our network's peak-
and off-peak business hours, followed by more tests using the Packet Blaster
tool and "The Cloud" WAN emulator from Shunra Software. We know
that The Cloud is reliable, and because it shares about 90 percent of the
Packet Blaster's feature set, we were able to compare QoS results and check
the Shomiti plug-in accuracy.
To begin the test, we went into the Module/Detail View menu. Doing so
adds several more toolbars and icons to the GUI. Next, we created and loaded
a new capture file. We initiated VoIP traffic over the network for a finite
amount of time, and then stopped the capture module. Then, we switched in
the Capture View/Multi-QoS menu. The initial Multi-QoS view shows only the
individual VoIP call and its affiliated IP addresses, start/end times, etc.,
but double-clicking this screen reveals another view. The ultimate view is
Detail View, where the drill-down method may be used to find errors in
specific packets.
Because our tests primarily used the H.323 protocol, we could see how the
detailed view(s) followed the process of call requests, setup, and
tear-down, using the techniques that are common to the ITU requirements for
a protocol stack. This way, not only can you analyze packet errors, you can
examine them in the larger scheme of an entire call, which is invaluable for
configuring managed IP networks with a voice element.
ROOM FOR IMPROVEMENT
After several weeks of testing, it became apparent to us that this tool
is not for the faint-hearted. We encountered several GUI quirks, which
largely reminded us of the way an apparently simple program like
HyperTerminal needs to be constantly refreshed when dealing with an outside
peripheral. There were occasions when the Surveyor software just didn't act
the way it was supposed to, but each issue was solved with a warm reboot and
a deep breath by the reviewers. We're not saying that Shomiti engineers
should dummy-down the product, because this normally results in some feature
sacrifice, but we do feel that the product could benefit from printed or
online tutorials designed for both datacom and telecom experts (as most
people know more about one than the other).
CONCLUSION
Surveyor 3.0 with the Explorer module, Packet Blaster, and Multi-QoS
plug-ins is a very useful product for predicting, diagnosing, and solving
obscure problems in VoIP networks, applications, and services. We highly
recommend this product with our Editors' Choice award, but we caution buyers
to spend a great deal of time in student mode: this is perhaps the most
complicated (and most powerful) Windows telephony tool you will ever use.
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