|We've seen many products over the years that do
many of the same tasks, but none seem to equal the DCOSS in usability or
comprehensiveness. An engineer from GL Communications visited us, and by
the time he left we were smiling from ear to ear, while the gears in our
heads were churning, thinking of the creative ways we could use their
product. The product can simulate T1, E1, SS7, and ISDN-PRI/BRI. It can
test for fax signaling, DTMF tones, line noise/energy, and voice quality.
It can also handle multiple trunks and protocols; for example, CAS and
The system we tested came on a portable all-in-one computer running
Windows NT Workstation 4.0 with service pack 6. Most systems come turnkey
from the vendor, as did ours, but end-users can install the Natural
MicroSystems boards and software on their own equipment if they desire.
(Although the GL systems are assembled by a third party, we really like
the shell design of the portable "lunchbox" PC they sent us. It
has a built-in LCD display that tilts out for easy viewing, an integrated
removable laptop-style keyboard with touchpad, and front-mounted mouse and
keyboard ports. All of the board slots are placed facing one side of the
box, right above the CD-ROM and floppy drives, with a cover that keeps
them safe. Check out the supplier's Web site at www.acmeportable.com.)
Configuring the DCOSS system in our laboratory was surprisingly easy.
We didn't have a T1-based product handy, which is unusual for us, but we
were able to conduct loopback tests across two spans. Our particular
system came with two T1/E1 boards, a T1/E1 analyzer board, and an ISDN-PRI
board. Running the DCOSS software for the first time requires selecting
various setup options for the boards and for the default system settings.
Included is an option to recall the factory recommended settings at any
time, which can be handy if too many custom options ever leave you wanting
to start from scratch. Starting the system for normal use requires that
you first start NMS's board initialization utility and that you open your
trunk lines. Of course, you can also load saved configurations. Overall,
we were very impressed with how fast the system went from sitting in its
shipping crate to successfully simulating T1/E1 trunks on our workbench.
The DCOSS system we received was a beta version, and the documentation was
not ready yet. We received the user's manual from the previous version,
plus release notes for the new version. The manual was good, with
sufficient screen captures, but it's clearly written for a knowledgeable
For the online help, all that existed was "About"
information. This option actually contains useful details about the
product, system files, settings, etc., rather than just the typical
copyright information. We feel this is a nice touch and indicates that GL
Communications' technical writers are thoughtful in their work.
Sometimes writing about a product's features is the most difficult
part of a review, simply because there are so many of them and because
they are equally important. This is the case with the DCOSS product. There
is the excellent GUI and the moderate learning curve. There is the manual
call generator, the bulk call generator and scheduler, and the test/script
writing feature. There are the fax tone/DTMF/energy testers, the
multistage logging and import/export options. There is T1, E1, BRI/PRI,
SS7, CAS, R1, and T1/E1 analysis. And as of this fall, there will also be
VoIP testing software.
Once the boards are cabled into your test product and the DCOSS
software is loaded, and once the board drivers are initialized, the next
question is, "What to do?." On top there are four pull-down
menus -- File, View, Functions, and Help. Beneath that, there is a
toolbar. The meat of the interface has three sections: a call status
window on the top left, divided by timeslots of the current trunk; a phone
handset status indicator on the bottom left, divided by open channels; and
a call records window on the right, which shows real-time data on every
call. The windows and their contents change dynamically as you conduct
various software operations, but the basic layout stays the same.
Bulk call generation and scheduling are the most important product
features, accessed through the Function menu. This option is very complex,
much more so than it appears from an initial glance at the control window.
Bulk calling can be accomplished with any combination of timeslots, or
with any train of incremental timeslots. To do this, there are options for
calls to jump to the next available timeslot, the selected timeslot, or to
synchronize all calling to happen simultaneously. You can also configure
incremental calling for every Xth timeslot, and you can copy and paste
configurations across trunks, which is a great time-saver.
Another time-saver is the ability to release DTMF digits at various
points in the calling pattern, using the dial offset and dial duration
options. The features are nearly identical for the twin bulk call
reception menu, which serves to test your product's inbound calling
features. The scripting feature is the most powerful option, whereby you
can manually enter each precise call option and action, and you can create
templates/library actions for future use. You can even create infinite
levels of subscripts, so the bulk call generation is limited mainly by
More features are accessed through the pull-down menus. From File,
there are setup options for the system, protocols, and system status. This
is also where you can configure ANI reception, DID routing, and
import/export options. The View menu is equally powerful and has many
choices. There are views for call records/detail, call records/all, and
call records/incomplete calls. There are two views for call status, plus
views for real-time status, phone handset status, and call statistics.
Other views include various captured events, energy detection (for testing
features like taking action on a long pause in a user's reaction to an IVR),
call records queries, and digital trunk alarm status.
From Functions, you can start DCOSS's dual manual call generators.
Each call generator lets you control all of the trunk's time slots
individually. Within these windows, you also have access to the system
phonebook, and to a "release all calls" toggle. For basic
testing, the manual call generators are very useful just to see how well
your product's intraextension dialing works.
The remaining Function menu items, excluding the script configuration
utility and a database reset option, have to do with what happens while
your test calls are being generated or received. These options are all
customizable, and they include voice files, faxes, DTMF/MF tones,
frequency tones, and a call quality criteria setting. All of these choices
are usable and were clearly designed by people who have legitimate CTI
Since we've used the simulators and call generators of several other
companies, we had some idea of what to expect from the DCOSS.
Unfortunately, those expectations were relatively low; our experience with
other T1 simulators dictates that they are very difficult to program.
Therefore, you can imagine the joy we experienced when we had multiple T1
spans successfully communicating in (literally) just a few minutes, after
one day of training.
At first, we thought that maybe we were actually getting smarter. We
soon realized, however, that DCOSS's usability is a result of the Windows
interface and intentional simplification of many telephony settings. This
concerns us, however, because there is a dilemma when you may actually
want to access some of those settings. After a few weeks of using the
product, we are convinced that enough of the settings are available for 90
percent of everything you'll need to do.
After placing and receiving hundred of generated calls over both T1 and
E1, we began to ponder new ways to test this product. We generated voice
prompts, faxes, and DTMF tones, all using the call acceptance criteria
tests. The criteria testing made us yearn for a full VoIP tester with PSQM,
MOS, etc., all of which we're told is coming in a new version toward the
end of this year.
Next, we tested the scripting. One scripting feature left us quite
impressed. When developing a bulk call script, the program makes it nearly
impossible to go wrong, because only allowable commands can be typed at
given points. So, if you try to make a call before selecting a timeslot,
or if you try to measure fax quality without first sending or receiving a
fax, the system won't let you script it. This makes scriptwriting much
easier for beginners, because they don't need to be expert programmers,
and the debugging is dynamic.
We also spent many hours testing trunk configurations, scheduling
properties, and most of the other miscellaneous features. We like how
administrators can interrupt and edit a script in progress, in many cases
without having to stop the script. We like the advanced levels of call
logging, which also can be frozen, examined, and restarted while the
logging continues behind the scenes. Also, we liked the ability to place
extension-to-extension calls, and we liked the ease with which we could
generate system templates for future testing.
ROOM FOR IMPROVEMENT
As the GL engineer demonstrated the DCOSS for us, two concerns soon
arose. The first is that the system does not ship with a network card
installed. We're told that this is to save space for the numerous
full-length telephony boards, and that many customers install a network
card on their own. In our opinion, this should be a standard feature.
Apparently, some people at GL agree, because the second criticism we have
-- that there should be a client-server version -- is already a planned
feature for the next release, along with the VoIP components mentioned
above. Lastly, we'd like to see the bulk call generator and the scheduler
integrated into a common GUI.
Whether your interest is the laboratory, the sales call, or the
tradeshow floor, the DCOSS system is a great solution, especially because
of the minimal training required to use it. It is easier to learn and use
than most of its competition, it is fairly priced, and it flaws are all
easily fixed or improvements are planned for upcoming versions. We highly
recommend this product.
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