017 021 fnne7oi4j72p2gm6p3y7vso5l47o2jifykbbqji FNNE7OI4J72P2GM6P3Y7VSO5L47O2JIFYKBBQJI


Internet Routing Architectures (CISCO):Evolution of the Internet Previous Table of Contents Next The very high-speed Backbone Network Service (vBNS) The very high-speed Backbone Network Service (vBNS) project was created to provide a specialized backbone service for the high-performance computing users of the major government-supported SuperComputer Centers (SCCs) and for the research community. The vBNS will continue the tradition that NSFNET has provided in this field. The vBNS will be connected to the NSFNET- specified NAPs. On April 24, 1995, MCI and NSF announced the launch of the vBNS. MCI duties include the following: •  Establish and maintain a 155 Mbps or higher transit network that switches IP and CLNP, and connects to all NAPs. •  Establish a set of metrics to monitor and characterize network performance. •  Subscribe to the policies of the NAP/RA manager. •  Provide for multimedia services. •  Participate in the enhancement of advanced routing technologies and propose enhancements in both speed and quality of service that is consistent with NSF customer requirements. The five-year, $50-million agreement between MCI and NSFNET will tie together NSF's five major high performance communication centers: •  Cornell Theory Center (CTC), in Ithaca, New York •  National Center for Atmospheric Research (NCAR) in Boulder, Colorado •  National Center for SuperComputing Applications (NCSA) at the University of Illinois at Champaign •  Pittsburgh SuperComputing Center (PSC) •  San Diego SuperComputer Center (SDSC) The vBNS has been called the R & D lab for the 21st century. The use of advanced switching and fiber optic transmission technologies, Asynchronous Transfer Mode (ATM), and Synchronous Optical Netwok (SONET) will enable very high-speed, high-capacity voice and video signals to be integrated. The NSF is already in the process of authorizing use of the vBNS for "meritorious" high-bandwidth applications, such as using super-computer modeling at NCAR to understand how and where icing occurs on aircraft. Other applications at NCSA consist of building computational models to simulate the workings of biological membranes and how cholesterol inserts into membranes. The vBNS will be accessible to select application sites through four NAPs in New York, San Francisco, Chicago, and Washington, D.C. Figure 1-5 shows the geographical relationships between the centers and NAPs. The vBNS is mainly composed of OC3 /T3 (OC12 is in the process of being deployed) links connected via high-end systems, such as Cisco routers and Cisco ATM switches. Figure 1-5  Overall map illustrating vBNS geographical components. The vBNS is a specialized network that emerged due to continuing needs for high-speed connections between members of the research and development community, one of the main charters of the NSFNET. Although the vBNS does not have any bearing on global routing behavior, the preceding brief overview is meant to give the reader background on how NSFNET covered all its bases before being decommissioned in 1995. Moving the Regional Providers As part of the NSFNET solicitation for transitioning to the new Internet architecture, NSF requested that regional networks (also called mid-level networks) start transitioning their connections from the NSFNET backbones to other providers. Regional networks have been a part of NSFNET since its creation and have played a major role in the network connectivity of the research and education community. Regional network providers (RNPs) connect a broad base of client/member organizations (such as universities), providing them with multiple networking services and with Inter Regional Connectivity (IRC). The anticipated duties of the Regional network providers per the NSF 93-52 program solicitation follow: •  Provide for interregional connectivity by such means as connecting to NSPs that are connected to NAPs and/or by connecting to NAPs directly and making inter-NAP connectivity arrangements with one or more NSPs. •  Provide for innovative network information services for client/member organizations in cooperation with the InterNIC and the NSFNET Information Services Manager. •  Propose and establish procedures to work with personnel from the NAP manager(s), the RA, the vBNS provider, and other regional and attached networks to resolve problems and to support end-to-end connectivity and quality of service for network users. •  Provide services that promote broadening the base of network users within the research and communication community. •  Provide for, possibly in cooperation with an NSP, high-bandwidth connections for client/member institutions that have meritorious high- bandwidth applications. •  Provide for network connections to client/member organizations. In the process of moving the regionals from the NSFNET to new ISP connections, NSF suggested that the regional networks be connected either directly to the NAPs or to providers connected to the NAPs. During the transition, NSF supported, for one year, connection fees that would decrease and eventually cease (after the first term of the NAP Manager/RA Cooperative Agreement, which shall be no more than four years.) Table1-1 lists some of the old NSFNET regional providers and their new respective providers under the current Internet environment. As you can see, most of the regional providers have shifted to either MCInet or Sprintlink. Moving the regional providers to the new Internet architecture in time for the April 1995 deadline was one of the major milestones that NSFNET had to achieve. Table 1-1 Example regional transitions to new providers. Old Regional Network New Internet Provider Argone CICnet BARRnet MCInet CA*net MCInet CERFnet CERFnet CICnet MCInet Cornell Theory Ctr. MCInet CSUnet MCInet DARPA ANSnet JvNCnet MCInet MOREnet Sprintlink NEARnet MCInet NevadaNet Sprintlink NYSERnet Sprintlink SESQUINET MCInet SURAnet MCInet THEnet MCInet Westnet Sprintlink Previous Table of Contents Next

Wyszukiwarka

Podobne podstrony:
017 021 ouzgz724vjs33zhtphpip3a3v3cg2bzmhbmdh7i
017 10 (2)
017 18 (2)
017 01
020 021
017 00 (3)
021 024 ltxltr6ohqcqdf7yfxcgd2njrgy7wlbryf4vaea
F C 021
017 020
013 017 xqywift6v6e33vr4cz65nsvkwreuzvewtd4o3ea
017 16 (3)

więcej podobnych podstron