The EXTender 3000 enhances your current digital phone’s capabilities by allowing
you to connect them to a remote office. The EXTender uses an internal ISDN interface to a
BRI line and provides the remote office with the all the functions of the phones in the
main office, wherever the remote office is located.
In addition, the EXTender will allow the remote user access to the company LAN. This
essentially allows a user to access voice mail, the office intercom system, and any
computers on the company’s LAN. In addition, a phone call will never be missed, since
the digital phone at the remote site is actually an extension of the company phone system.
Since it utilizes ISDN technology, the connection to the office is quick and allows for
efficient telecommuting. At $2,400, the EXTender obviously isn’t for everyone. In
addition, it requires two ISDN lines for each user, but with ISDN lines, you know
it’s going to be fast.
INSTALLATION
To configure the EXTender, we used a two-port Teltone ISDN simulator with the Switch
Module at Port 1 and the Remote Module connected at Port 2. We plugged an RJ11 cable into
a Norstar KSU and the Switch Module port. Then we connected the Switch Module to the ISDN
network (the Teltone ISDN Simulator) with an RJ45 cable.
To configure the SPID numbers and the DN numbers in the Switch module, we used the
HyperTerminal to access the Switch Module through DB9 straight through the serial cable.
The most difficult part of the installation was figuring out whether we were actually
connecting with the Switch Module. Apparently, the Switch Module runs through a series of
flash sequences of red, green, and yellow. After a series of very rapid red blinks, the
module blinks green three times and red once. Then, the module displays three sets of
yellow flashes, with each set giving eight flashes.
It was during this sequence of yellow flashes that we had to type the word
"MENU" in the terminal program. This required some timing, but the manual was
fairly explicit on this step, so we were prepared for it. At this point, the Switch
Configuration menu appeared, and we were able to configure the ISDN network switch type,
the SPID and DN numbers for the Switch ISDN line, and the TEI type.
After setting up the Switch Module, we turned our attentions to the Remote Module
configuration. We connected the Remote Module to our Meridian digital phone with an RJ11
cable and to the ISDN simulator with an RJ45 cable. When we powered up the Remote module,
it ran through the power up test until the phone set displayed the words "Go
Online?"
Configuring the Remote Module turned out to be much simpler than configuring the Switch
Module because we were able to use the digital display on the phone. From the phone’s
LCD display, we easily set the SPID and DN numbers. From the Remote Module display, we set
the PBX phone number and the remote phone number. We scrolled back to the original menu
and selected OK to go online. The phone gave a flash, letting us know that it had made a
connection with the PBX, and we noticed that the displays on both the Switch and Remote
Modules were flashing green, telling us that we were ready to continue.
DOCUMENTATION
We received two copies of the manual, one with the Switch Module and one with the Remote
Module. This was a sign of good planning, since the modules could be deployed miles apart.
The manual was complete and, appropriately, covered the material at the
technician’s level. We were glad the manual included detailed information on those
pesky blinking lights. It outlined the meaning of each sequence of blinks, thus keying us
into which manual topics needed further study. Without this portion of the manual,
troubleshooting the EXTender would be difficult, to say the least.
FEATURES
- Extends Meridian PBX or Norstar KSU phone system functionality to a remote site.
- Enables communication between Remote Module and Switch Module by transmitting signals
over a single ISDN B channel on an internal Terminal Adapter.
- Compresses speech to 32-Kbit ADPCM format in combination with the phone’s signaling
data and the user’s data port information.
- Allocates bandwidth dynamically, detecting silence within speech. (Allows for a variable
data rate of up to 57.6 Kbps.)
- Permits access to the company LAN. (The 3000e model uses the second channel for an
analog port and an Ethernet port for access to the company LAN; the 3000t model uses the
second channel as an analog port and an RS232 adapter to access the company LAN.)
- Changes from one EXTender model to another via software upgrades.
- Allows your remote Meridian or Norstar phone the functionality of the office desk set.
- Lets you use your computer to configure the Switch module, via a terminal emulation
program.
- • Allows you to configure the Remote module with your Meridian or Norstar phone.
- • Takes advantage of Call On Demand (COD), a feature that allows the Remote Module
to disconnect from the Switch Module until a COD mode reconnection event occurs.
OPERATIONAL TESTING
Once we had the system properly configured, it was fairly simple to determine that the
product was working as advertised. With the Meridian digital phone attached to the Remote
Module, we were able to dial other extensions as if we were connected directly to the
Norstar KSU. The sound quality over the connection was fine, with no appreciable drop in
sound quality. From there, we also verified that we were able to access the voice mail
system with all its functionality. Furthermore, the EXTender gave us the ability to page
over the PBX intercom system. In addition, we could transfer calls to other extensions.
We dialed out on the phone, noting that we had to dial a "9" to get out of
the PBX system. In addition, we dialed into an auto attendant/voice mail hooked into the
Norstar PBX from an outside line. We were greeted by the short message that had been
recorded for the Norstar system and then asked for an extension number. In response, we
typed in the extension where the EXTender Switch Module was connected. Our phone call went
through to the digital phone as if it were connected directly to the PBX. Since we were
testing this all in the lab, we had to imagine that the phones were in different cities as
we were placing the phone calls. This meant that the digital phone we had attached to the
Remote Module was truly an extension of the PBX even though it could be miles away over
the ISDN network.
Our next step was to find an analog phone to connect to the Remote Module. From this
phone, we were able to get a dial tone and even dial out of the system, even when the
digital phone was in use. This is because the analog phone port on the Remote Module uses
the second B channel, keeping 64 Kbps between the Remote and Switch Modules while the
other 64 Kbps is reserved for data transmission. Each model uses the second B channel in a
different way. The 3000s uses it exclusively as an analog port, the 3000e combines analog
and Ethernet on the channel, while the 3000t uses the channel for analog and RS232
transmissions.
Our model, the 3000, lacked Ethernet capabilities. (It had been sent before the 3000e
and 3000s models were ready.) We were reluctant to finish the review without testing the
Ethernet port, so we asked MCK Communications if we could arrange a software upgrade. We
learned that all the models are firmware upgradeable to each other, so the EXTender can
change to comply with any changes to the company network.
MCK sent us an e-mail containing the Web URL for the download page so we could
transform our machine into the EXTender 3000e. We downloaded the file, about 1 Meg in
size, and called MCK for a feature code that would allow us to send the file to the module
as an ASCII file through the HyperTerminal program. The Feature Code was input to the
system through the Remote Module via the Meridian digital phone. Then we accessed the
Switch Module via the HyperTerminal and uploaded the file, which took about 10 minutes.
Afterwards, we had to reconfigure the SPID and DN numbers for the module. We had to do
the same for the Remote Module, but we had a choice of methods for uploading the file.
Since the RS232 connection through HyperTerminal operated at only 9600 bps, uploading
through the ISDN connection with the Switch Module at 57.6 Kbps was the better choice.
Again, we had to set the SPID and DN numbers for the Remote Module before we attempted to
connect to the company network.
When we used the HyperTerminal to reenter the Switch Module, we noticed we had more
choices in the menu. We were given options to configure the Ethernet by PPP or by
Bridging. From the PPP menu, we could change the local username and password, and the
remote username and password, and we could request local or remote authentication.
ROOM FOR IMPROVEMENT
While the units worked well once configuration was complete, the configuration itself was
difficult. Admittedly, our setup was unusually complicated, since we had to use a
simulator to act as our ISDN network. Most users would simply use the specifications given
to them by their phone company, and thereby escape any reconfiguring chores. At any rate,
configuration could be simplified with the addition of an LCD or other sort of display on
the MCK units. (We were a little perplexed by all the blinking lights.)
The other place we hit a small snag was when dealing with the Ethernet port, which is
present in both modules. Basically, we tried to view the corporate network through a
computer connected to the Remote Module via the Ethernet port. We failed. So, we tried
some other configurations until we tried the simplest of them all, a local network of only
two computers. The computers couldn’t communicate, so we returned to the manual.
Eventually, we found an obscure note indicating that the 10Base-T Ethernet port was
included, but not functioning in the current release. We placed a call to MCK and arranged
for a software download so we could configure the EXTender to take Ethernet traffic.
Perhaps our downfall in this portion of the test was that we were testing the equipment
and we wanted to know the function and efficiency of every port. When this port
didn’t seem to do anything, we were confused. But we suppose better documentation
would help people avoid this trap.
CONCLUSION
While the MCK EXTender is not the most user-friendly hardware solution to telecommuting,
it certainly performs as advertised. Installation was a one-time process. After that, the
system operated smoothly. We were able to use our Meridian digital phone from a remote
site and access all the functions of the company PBX. In addition, after upgrading to the
MCK EXTtender 3000e, we were able to access all the functionality of the company network.
Incidentally, when we phoned MCK about the software download, the MCK rep mentioned
that he was at home, using the EXTender himself. This was just more proof that the
EXTender does what it was engineered to do, and that is to allow people to telecommute. |
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