Video-Conferencing Test
911-999-9999
(911-999-9999)

ISDN Test Number
911-999-9999
(911-999-9999)

Calls cost
$1 per min, per channel.
911 no.'s are digital bonding loops

For questions call:
Customer Service
(314) 555-1212

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Frequently Asked Questions

How do we use the Loopback test service?

What is a Loopback?

How is a Loopback test done?

Why is a Loopback test useful?

Can routers be tested using Loopback's test facilities?

What types of lines can be tested by Loopback?

How do I test the Intel Proshare system?

How do I test a unit which requires dialing two phone numbers?

Why can't I connect at 128k?

Why can't I get on-line with an Nx64 bonding call.

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How do we use the Loopback test service?
Using your equipment's typical configuration set-up, enter the appropriate dial code along with the appropriate Loopback phone number.
If you are connecting a video-conference call, you will see yourself in both the local and remote video windows after the call is completed. ISDN communication equipment will see the looped data. Typical tests, such as a BERT test, can be performed.
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What is a Loopback?
A loopback occurs when a receiving communications device takes all of the data which is received and returns that data unchanged back to the sender. In other words, the received signal was looped back to the sender. In the telecommunications industry, this test is called a loopback test.
Loopback, Inc. furnishes general looping facilities for all types of ISDN bonded calls. Equipment is compliant with general industry standards.
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How is a Loopback test done?
Once the signal has been received, the looping communications device makes sure that the data signal is in sync with the clock signal, and then presents both to the looping device to be sent back to the source where the test was initiated.
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Why is a Loopback test useful?
A Loopback is a good test because the sender is able to test the sending equipment, the communications path, and the receiving equipment. This test can be done with only one person. In the case of video systems, the sender can both see and hear him/herself when connected to a looping system. Since the calling party only uses one location, after the test is completed, the caller has verified the operation of the equipment at the calling location.
Typically, only one of the two locations will have a problem. If there is no problem at either end, then the problem is typically an incompatibility between the two systems. This type of problem needs to involve qualified users at both ends of the communication link to resolve the problem.
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Can routers be tested using Loopback's test facilities?
A loopback can be used to test any communication system as long as the sending system can sync up with its own signal.
In the case of a router, if a password system such as "CHAP" is used, it must be turned off during the test. Doing this will not cause a breach of any corporate security policy because you will not be connecting to a remote system that is capable of establishing a link. You are dialing into a system that will only receive data and send it back to you. As soon as the test is over the security feature should be re-enabled.
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What types of lines can be tested by Loopback?
LoopBack, Inc. is set up to test any ISDN connection. The service must be accessed via LEC (i.e., SW Bell, PAC Bell, NYNEX, etc.) provided lines. If your network has an option to dial service within a long distance carrier, you must access the LEC provided interface to use the Loopback service.
If you have trouble connecting, please contact your local technical support to determine how to utilize Loopback's service. If you and/or your administrator have any questions about this, please contact us.
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How do I test the Intel Proshare system?
You must create a sub-section in the "ini" file prior to making a test call using the Proshare system. Create a section in the c:\proshare\psuser.ini file called [PSH320\Caps]. Under this heading will be an entry which determines whether the T.120 functionality is enabled. The T.120 standard does not support data sharing over a loopback test. Therefore, to test the Proshare system you must disable the T.120 function temporarily.
Once you have created or found the "[PSH320\Caps]" section in the psuser.ini file you need to change T.120 Enable=1 to T.120 Enable=0. Look at the following lines for an example.
- Heading in the psuser.ini file with T.120 disabled.
Disable the T.120 function and run your test. After completing the test, you will want to enable the T.120 function. You can leave this new section in your ini file to simplify future testing.
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How do I test a unit which requires dialing two phone numbers?
Follow the normal system procedures and enter the same Loopback phone number into both dialing positions. Loopback will answer both calls.
This procedure is consistent with the industry standards.
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Why can't I connect at 128k?
Try configuring your unit for a 112 call which is a combination of 2 56k channels. This is a standard capability of most units.
If you are able to connect with a 112k call, you should call the phone company and report a trouble ticket. The problem is that your unit is probably being routed through a location which can only handle the lower 56k bandwidth. Your BRI should be able to establish a 128k connection to Loopback.
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Why can't I get on-line with an Nx64 bonding call?
This question is similar to the question above. Try to establish an Nx56k call to Loopback. If this connection is successful, then your lines may be routed through a trunk group which can not handle 64k traffic.
Open a trouble ticket with the phone company and they should be able to trouble shoot your problem.
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