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AT&T Technologies was formed of Western Electric, the manufacturing arm of AT&T, and AT&T Bell Telephone Laboratories (Bell Labs), the research and development organization. Of all the AT&T entities, only Bell Labs was allowed to retain the Bell name. The RBOCs, in consortium, formed Bell Communications Research (Bellcore) as a R&D entity. Bellcore continues to focus on the needs of its RBOC client/owners in terms of software R&D, standards development and other requirements. Under the terms of the MFJ, Bellcore is precluded from involvement in the physical sciences [6-11] and [6-12]. The RBOCs recently announced their intentions to divest Bellcore, as their individual interests no longer are compatible in a deregulated environmentin fact, they are now competitors.
In the United States, LECs traditionally had the exclusive rights to local and intraLATA markets, although this policy either eroded or was modified in many states; Connecticut, for instance, has allowed local exchange competition since July 1, 1994. The Telecommunications Act of 1996, which will be discussed in Chapter 16, has set the stage for complete and open competition for virtually all services. However, the distinctions remain valid at the time of this writing.
In addition to the RBOCs and their LEC subsidiaries, approximately 1,500 independent telephone companies exist, according to the United States Telephone Association. In fact, GTE is the fourth largest LEC in the United States, ranking behind BellSouth, Bell Atlantic, and Ameritech. Sprint, Southern New England Telephone, and ALLTEL are among the larger independents.
The Telecommunications Act of 1996 will change this landscape dramatically. Casting aside the MFJ, that act allows the IXCs to immediately begin competing with the LECs for local and intraLATA service. Similarly, the RBOCs can offer interLATA long distance service outside the states in which they operate as LECs. Once the RBOCs have satisfied certain local competition requirements, they will be allowed to offer interLATA toll services within their home states, as well.
InterEXchange Carriers (IXCs or IECs)
These are responsible for long-haul long distance connections across LATA boundaries. The IXCs networks are connected to the LECs through a point of presence (POP) which typically is in the form of a tandem switch. An InterLATA call originating in a LEC serving area is recognized as such and is passed to the IXC through an access tandem switch which, in turn, is connected to the POP via dedicated trunks leased from the LEC (Figure 6.3). Alternatively, the IXC may collogate the network termination equipment in the LEC exchange office, assuming that space is available and that secure physical separation can be established and maintained.
Figure 6.3 Interconnection between LEC and IXC via access tandem switch and via collocated termination equipment.
Increasingly, large users seek to gain direct access to the IXC POP, bypassing the LEC switching network in the process. Such a bypass arrangement typically is effected through a leased line provided by the LEC; alternatively the LEC can be completely bypassed through a direct link, which often is in the form of microwave provided by the IXC. IXCs also can be accessed through a CAP/AAV, which typically provides fiber optic cable connections directly from the customer premise to the IXC POPs, totally bypassing all LEC facilities.
IXCs, by definition, are facilities-based, or heavy, carriers. While they prefer to contract directly with large end users, they also often work through resellers (light carriers) and agents. Of the 400 or so heavy carriers, AT&T with 55.2% of the market, MCI with 17.4%, Sprint with 10.1% and LDDS WORLDCOM(previously Wiltel) with 4.7% are the largest, by far. Based on 1994 statistics from the FCC; the total size of market was $67.351 billion [6-2].
Competitive Access Providers (CAPs)
CAPs, also known as Alternative Access Vendors (AAVs) provide an alternative means of connection between large user organizations and IXCs, completely bypassing the LEC network in the process. CAPs deploy high-capacity, fiber optic facilities from IXC POPs to areas where there exist a high density of large user organizations (commercial office parks and urban business areas) as depicted in Figure 6.4. In many cases, the CAP will extend the fiber optic connection directly to the users CPE, such as a PBX.
Figure 6.4 End user access to IXC via CAP, bypassing the LEC.
There are numerous benefits of such an approach, including the fact that the performance characteristics of the fiber optic facilities are far superior to the traditional LEC copper local loop. Additionally, the CAP network automatically provides a measure of local loop redundancythe CAP facilities are used for IXC access, while the LEC local loops can still be used for IXC access in the event of a failure in the CAP network. Further, the CAPs fiber optic network generally is redundant, thereby minimizing the likelihood of a service-affecting network failure. As the fiber optic network also offers substantial bandwidth, the user organization typically can increase its level of access to the IXC much more quickly and easily than would be the case through a LEC connection. Call set-up time (speed of connection) also is improved, as the LEC CO, tandem switch and access tandem switch all are bypassed. Finally, the costs of IXC access often are much reduced as the CAPs unregulated rates generally are highly competitive; additionally, Subscriber Line Charges (SLCs) are avoided.
CAPs/AAVs operate most especially in the United States, where they now provide Centrex service, local calling service, high speed data services, and certain enhanced services. CAPs operating in the United States include Metropolitan Fiber Systems (MFS), Electric Lightwave, and Teleport Communications Group (TCG) [6-1].
International Record Carriers (IRCs)
IRCs are carriers of record which provide communications transport services across national borders. Access to the IRC from the LEC or IXC domain is accomplished by connection to an International Gateway Facility (IGF) which connects to the IRCs transmission network. Contemporary IRC transmission facilities are largely satellite and submarine fiber optic cables, the latter often being jointly owned through consortia. Examples of IRCs include AT&T, Cable & Wireless (C&W), HongKong Telecom International (HKTI), and MCI.
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