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This Section
Modem Test at the INI (Indoor Network Interface)

Introduction
This procedure enables customers living in apartment complexes, condominiums, or multi-family buildings the ability to test DSL speeds and synchronization rates directly at the Indoor Network Interface(INI). By testing the modem directly at the INI all inside wiring and filters/splitters are eliminated from the circuit. Note: If you have a standard, single-family house please see the Test at the NID FAQ.

The best method for testing is to have both the modem and the PC as close to the INI as possible and using the shortest RJ-11 cable available between the INI and the modem. Since the PC is required to access the line statistics you may have to move the PC to another room closer to the INI. If it is impossible or hard to move the PC, it is better to use a short RJ-11 cable from the INI to the modem and then connect a long RJ-45 Ethernet cable to the PC. You do not have to log in to BellSouth to obtain the line statistics, you simply need the modem to synch with the DSLAM. Important Note: If you are using a separate router in conjunction with your modem you will have to connect the modem directly to a single PC in order to access the modem's interface.

    Required Equipment
    -Flat Head Screwdriver (may not be required for all NIDs)
    -High quality RJ-11 modem cable (use the shortest length possible)
    -PC or laptop (located as close as possible to the NID)
    -Ethernet cable (if using an external Ethernet modem)

Step 1 - Baseline testing the modem
Important Note: Before testing at the INI you must establish an operational baseline reference. Pull your line stats and save/print all of your previous modem logs before you change anything or troubleshoot. Some modems have the ability to test attainable line rate, relative bandwidth capacity, power, attenuation, and signal-to-noise ratio. If available, these measurements are the most accurate assessment of line quality. For more information about capturing line statistics and what the values and numbers mean please reference the following:

Motorola 2210
Westell Line Statistics
SpeedTouch Home Line Statistics (Command Line Interface)
SpeedTouch Home Line Statistics using Alcatool (GUI Interface Alternative)
2Wire Line Statistics
Cayman Line Statistics
What do all the line statistics values mean? Are my numbers good?


Step 2 - Identify and locate your INI
The INI is the point where the telephone cable and service enter your apartment. Common locations can include kitchens, laundry closets, or bedrooms. Note: Not all apartments have INIs. Some may have a residential NID outside, a demarc or junction box that is not accessible, or no place (other than the standard wall jack) available for testing. A common INI is shown below in Figure 1.

Figure 1


Step 3 - Connecting modem to RJ-11 test jack on the INI
On the bottom of the INI you will find one or more (depending on the number of phone lines in your apartment) RJ-11 Test Jacks. This is where the Telco network stops and your private apartment network begins. Disconnect the short operational wire to access the test jack. Plug one end of your test cable into the open RJ-11 test jack and connect other end into the line in jack on your modem as shown in Figure 2 below. Helpful Hint: To eliminate the modem cable itself being the problem, use a new or known good RJ11 cable (or a least a different one).

Figure 2

Pictures by Andy Houtz


Step 4 - Testing modem at the INI
All wiring within the apartment is now bypassed and there will be no dial tone on any phones while testing. Best advice ever: Run the test from the NID for as long as possible. You may have an intermittent issue that doesn't show up if you only check for a minute or two. If you are experiencing troubles at a specific time try and test in that time frame, if possible. Make sure you recheck the modem logs too.

Step 5 - Returning to your operational configuration
Once completed, disconnect the test cable from the INI test jack and replace the operational wire. Ensure that all phones have dial tone. Connect the modem back to your standard operational configuration.

Step 6 - Analyzing the results:

Once you have pulled the modem/line statistics check the following link for detailed more information. What do all the line statistics values mean? Are my numbers good?

Your speeds or synchronization rates did not change or only slightly changed during test:

    One of two things may be wrong.

    1. The modem is bad.
    2. The local loop (wiring from your apartment to the Central Office) has problems.

    Either way, please call the Help Desk at 1-888-321-2375 and request a line check. A simple line check can test the local loop for problems. Depending on the results of the line test, the Help Desk will either send a technician to fix the line or replace the modem.

Your speeds or synchronization rates changed dramatically during test:

    Several things may be at fault and will require further troubleshooting.

    1. The DSL filters are not installed properly, not present on all devices, or simply gone bad.
    Many times the issue is the filters have been installed incorrectly. The BellSouth supplied filters have two outputs, one for phones/faxes/etc and the for DSL. It is very important that all phones/faxes/etc have a filter installed. Filters can also go bad for various reasons so just because a filter is installed properly does not mean it is functioning properly. To eliminate the filters as a cause of problem remove all filters and POTS devices from every jack in the home. Replace the filters and POTS devices one at a time and test the modem for any speed or synchronization changes. If your speeds drop off dramatically then replace that filter.

    2. Bad inside wiring (substandard wiring, cuts/staples/nails through the wires, improperly installed jacks, etc).
    Since inside wiring problems are extremely hard to track down we suggest that you install a Homerun. A homerun is a dedicated line that is strictly for data (DSL). It guarantees that POTS devices and DSL will not conflict or be carried on the same lines. A homerun also eliminates the need for the individual filters on every POTS device. A BellSouth technician can install a homerun in most cases and it is an easy way to avoid the hassles of rewiring your apartment or condo. There is a service charge for the install. Please call the Help desk at 1-888-321-2375 to schedule an appointment. Note: Most complexes have restrictions on repairs/replacement of wiring. Please check with your property management before you do any changes. Customers who have the aptitude and wish to do their own homerun wiring can find a tutorial outlining an installation here.

    3. You may have an alarm or satellite system.
    Alarms and satellite systems (even if they are not active and you do not have service) can cause major problems. You will have to install a specialized alarm filter or install a completely separate homerun to isolate the alarm or satellite system as shown here.

    4. Interference from other electrical devices.
    Move any electrical devices such as monitors, TVs, intercoms, HAM radios, wireless devices, halogen or fluorescent lights, etc as far from the modem as possible. If such devices can not be moved disconnect all electronic devices and connect them one at a time and check your speed and synchronization rates after each device is turned on (much the same way you checked for bad filters). If your speed drops dramatically after a certain device is powered than that is causing your problems. A simple hand held AM radio can also be used to track down noisy electrical problems. Tune the radio to a lower frequency that is not used by a station so you hear only static. Pass the radio near the suspected device and if you hear a major change in the amount of static that device may be causing the problems.

    5. A bad or incompatible surge protector.
    Some telephone line surge protectors are not designed for DSL and will create connectivity issues. Even if the surge protector is rated for DSL it may have gone bad or been hit with a lightning surge. In either case, simply bypass the surge protector and test again.

Andy Houtz DSL

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by Andy Houtz See Profile edited by FAQFixer See Profile
last modified: 2009-02-20 10:57:23