PDF of this tutorialDispatching on All Calls
Some ILECs, and many CLECs, dispatch personnel on every unbundled loop repair request, the way ILECs did before the local loop was unbundled. For example, a CLEC sends a technician to a POT bay. If the technician finds a dial tone, the CLEC turns the problem over to the ILEC.
In the past, a telco could simply dispatch into the MDF, and also dispatch out. Now, because telcos cannot do remote tests, and cannot test immediately, many of them have adapted this technique of sending someone on every call.
Even this method of unrestricted dispatch may not accomplish the telco's immediate service goals. If a telco does send a technician to the field, the technician might run into the DATU line conditioning problems cited above, and need additional equipment or assistance from someone in the central office. Suddenly, two or more technicians are involved in the service call, and the cost of the dispatch escalates. If a CLEC's market-share begins to approach 20 percent and the CLEC dispatches on all calls, the dispatch numbers and dispatch costs can add up quickly.
Using the Special Services Department
Some ILECs view unbundled loops as special services and therefore send their special services personnel. This can be a successful but very expensive strategy. Because special services personnel are an ILEC's most highly trained and highly paid technicians, the ILEC is using scarce and expensive resources to solve some problems, such as routine POTS service, that may not warrant this attention.
There are some other problems associated with using special services and the equipment they employ. If special services use switched maintenance access systems (SMAS) to access the unbundled loops, the need to run two jumpers and install three blocks significantly increases the amount of work at the MDF. Also, this method uses equipment that takes a long time to conduct tests, and therefore chokes the system.
Extending the POTS Testing System
Some ILECs try yet another approach. They attempt to extend the existing POTS system to the unbundled loop. However, as we have noted above, without connectivity between the unbundled loop and testing devices, testing cannot be carried out successfully. Also, old POTS testing methods cannot be used to pre-qualify lines for integrated services digital network (ISDN) and the various types of digital subscriber line (xDSL)—ADSL, HDSL, and VDSL—and do not address transmission problems such as loading and noise.
