Before examining the different methods of testing currently employed, the tasks that line testing must accomplish were considered. At the beginning of this tutorial, five broad business objectives that line testing can help meet were outlined. Now these objectives will be examined in greater detail.

The Need to Reduce Network Maintenance Costs

The biggest problems facing service providers are dispatching the right person to the right place and avoiding unnecessary dispatches. Testing before dispatch can help eliminate expensive and unnecessary dispatches, problems involving customer inside wire, or switch datafill error. If a telco does dispatch, it can improve its mean time to repair (MTTR) by providing accurate, automated information about the problem and by sending the right technician to the exact location in either ILEC or CLEC territory. An effective line-test system can make dispatches even more efficient by identifying multiple faults that can be fixed on a single dispatch.

The Need to Meet or Exceed Customer-Service and Network-Quality Expectations, as the Result of the Pressures of Deregulation

By identifying and utilizing all available pairs and prequalifying lines, testing can help speed up provisioning of ISDN lines. Testing after provisioning can help reduce post-installation trouble reports (I-reports). Proactive scanning and dispatch can help reduce the report rate. It has been estimated that one proactive dispatch can eliminate up to seven trouble calls. Testing also makes it possible to provide customers with more information about a problem. In addition, testing that identifies loaded loops and noise improves network quality for nonvoice calls and makes it easier to explain to customers why their modems are having trouble transmitting at 28.8 kbps or 56 kbps.

The Ability to Offer New Revenue-Producing Services

A company's use of an effective, properly designed line-test system makes it easier to offer new services, such as ISDN, xDSL, and caller ID.

The Ability to Incorporate New Technology and Cope with Growth and Change

The line test system must fit the service provider's network, working in all switches, remote switches, and DLCs in both standard and unbundled loops. It must support star, multidrop, or fiber-ring transmission structures. The system must also be able to grow with the network—devices must be easily added and upgraded.

The Ability to Protect Investments

A test system should be able to provide patterned test results to spot cables that have DC faults, water faults, load coil, or noise problems. This helps maintain the current system. A test system also needs to identify crosses and wets. Periodic automatic number identification (ANI) scans plus nightly automatic loop test (ALT) scans help accomplish this. In addition, a provider must track the inventory of its plant to know which numbers are working and which are not. This not only makes it faster and easier to assign new numbers, but also enables a better grasp of used and unused infrastructure so as to avoid unnecessary investment. Building databases that track telco infrastructure and having that data readily available boosts the productivity of the workforce.