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ATM provides a worldwide standard offering scaleable, meaning any size bandwidth required by the application, interoperability to all service providers and enterprises. The demand for WAN switches to form private enterprise ATM backbone networks is growing, especially outside the U.S. as Europeans and Asians are discovering the significant cost savings of ATM versus leased lines.

ATM integrates LANs and WANs with little capital investment into bandwidth efficient networks. Separate LANs and WANs are easily connected via ATM PVCs and inexpensive customer premises equipment. And a single network monitoring and management center can continuously watch over the combined network, providing peace of mind for little cost.

Since ATM is scaleable down to 16 Kbps (some service providers may allow access at 8 Kbps), the user only pays for the bandwidth necessary to perform the intended network function. PVCs are connected to the network continuously and the user pays for the access whether or not any data is actually transmitted. If the application does not require continuous access, then SVCs may be the answer since SVCs are built up for the duration of the transmission, then torn down. The user only pays access charges for the time the connection was built up. Even for SVCs, the user pays for the access while the circuit is connected whether or not any data was actually transported. Besides allowing the user to utilize bandwidth efficiently, ATM also optimizes the service provider backbone network bandwidth.

ATM consolidates voice, video, SNA, LAN, legacy data, and native ATM effortlessly into a single transmission medium. No hassle, no worries, and no sweat. As native ATM networks proliferate, there will be less need to aggregate non-native bit streams into a combined ATM bit stream. In the interim, affordable concentrators and aggregators are available to combine any mix of legacy bit streams into a single ATM bit stream.

Currently there are multiple transmission technologies and platforms available to choose from. Network features and capabilities were confined within the limits of each particular technology. Now, ATM goes far beyond the capabilities of current transmission technologies, allowing users to focus on service issues and forget about technology limitations.

ATM enables transmission interworking and promotes pain-free communications evolution by reducing interoperability problems with supporting multiple platforms and vendors. ATM provides more services and features than competing transmission technologies. ATM provides a global, seamless transmission technology, empowering GANs. And finally, ATM reduces user long-term operating and capital costs since a significant reduction in trunking and support costs is an ATM feature.

U.S. ATM Players

The ATM service providers offering access in national and large regional markets are MCI, AT&T, Sprint, Worldcom/MFS Datanet, U.S. West, GTE, Nynex, Bell Atlantic, Bell South, Pacific Bell, and Southwestern Bell. The ATM service features of import offered by each of these companies is listed in Table 8-1. Listed underneath the service provider’s name is the region covered by the service provider. Notice under GTE the region “Shotgun.” GTE does not offer a regional or national ATM service. The company provides ATM access in several cities across the country, coinciding with its presence in the local exchange markets.

For additional information regarding ATM suppliers, try the ATM Forum web page at www.atmforum.com. The ATM Forum lists member companies and the particular ATM services and equipment provided by them.

Company and region MCI Nationwide AT&T Nationwide Sprint Nationwide Worldcom/MFS Datacom Nationwide Ameritech Northern Midwest U.S. West West
ATM UNI NxDS-1, DS-3/OC-3, OC-12 (ICB) T1/T3/OC-3/OC-12 (ICB) T1/T3/OC-3 DS-1/DS-3/OC-3 DS-1/DS-3/OC-3/OC-12 DS-1/DS-3/OC-3
Service Classes VBR-nrt, VBR-rt,CBR, UBR VBR-nrt,VBR-rt CBR, ABR CBR, VBR-nrt, VB-rt (4Q98), ABR (4Q98) VBR-nrt,voice over VBR-nrt CBR, ABR CBR, VBR-nrt VBR, ABR,VBR-nrt, VBR-rt
Customer Network Management Plans to sub- contract to third-party vendor   Yes      
Backbone Platform GDC, Newbridge, 3Com Access Builder 9600/9300 Lucent, Cisco, Ascend NEC, Nortel Cisco, GDC, Lucent Lucent Newbridge
Frame Relay Interworking Yes Limited Limited Yes Yes Yes
Managed CPE ICB     Yes    
Number of Backbone Switches 24 POPs T1 UNI 300+ POPS,T3 UNI 240+ POPS   T3 UNI 18 U.S. POP. 4 Europe POPs    
SVCs 4Q98 Yes 1Q98 4Q98 4Q98 Yes
Oversubscription 10xport 200% 500% 200% 150% None
IMA Yes No Yes No No 1Q98
Network Reports On-line e-mail e-mail None e-mail none

Table 8-1. U.S. ATM service providers


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