AT&T was awarded the Database and Directory Services, and Network Solutions was awarded the Registration and NIC Support Services.. Directory and Database Services The implementation of
Trang 1• Information services for various federal agency backbone networks were provided by the sponsoring agencies NASA, for example, provided NSI information services
• Internet registration services were provided by DISA NIC, operated by Government Services, Inc (GSI)
• Information services for campus-level providers were provided by NSFNET mid-level network organizations
• Information services for NSFNET mid-level network providers were provided by Merit, Inc
Under the new solicitation, NIS managers should provide services to end-users and to campus and mid-level network service providers They should also coordinate with other mid-level and network organizations, such as Merit, Inc
Creation of the InterNIC
In response to NSF's solicitation for NIS managers, in January 1993 the InterNIC was established as a collaborative project among AT&T, General Atomics, and Network Solutions, Inc.[] It was to be supported by three five-year cooperative agreements with the NSF During the second-year performance review, funding by the NSF to General Atomics stopped AT&T was awarded the Database and Directory Services, and Network Solutions was awarded the Registration and NIC Support Services
Directory and Database Services
The implementation of this service should utilize distributed database and other advanced technologies The NIS manager could coordinate this role with respect to other organizations that have created and maintained relevant directories and databases AT&T was providing the following services under the NSF agreement:
• Directory services (white pages):
This provides access to Internet White Pages information using X.500, WHOIS, and netfind systems
The X.500 directory standard enables the creation of a single worldwide directory of information about various objects of interest, such as information about people
The WHOIS lookup service provides unified access to three Internet WHOIS servers for person and organization queries It searches the InterNIC directory and Database Services server for nonmilitary domain and non-Point-of-Contact data The search for MIL (military) domain data is done via the DISA NIC server, and the POC data is done via the InterNIC Registration Services server
Netfind is a simple Internet white pages directory search facility Given the name of an Internet user and a description of where the user works, the tool attempts to locate information about the user
Trang 2• Database services:
This should include databases of communications documents such as Request For Comments (RFCs), Internet Drafts (IDs), IETF Meeting Minutes, IETF Steering Group (IESG) documents, and so on The service could also contain databases maintained for other groups with a possible fee
AT&T also offered a database service listing of public databases, which contains information of interest to the Internet community
• Directory of directories:
This service points to other directories and databases, such as those listed previously This is an index of pointers to resources, products, and services accessible through the Internet It includes pointers to resources such as computing centers, network providers, information servers, white and yellow pages directories, library catalogs, and so on
As part of this service, AT&T stores a listing of information resources, including type, description, how to access the resource, and other attributes Information providers are given access to update and add to the database The information can be accessed via different methods, such as Telnet, ftp, e-mail, and World Wide Web
Registration Services
The NIS manager was required to act in accordance with RFC 1174, which states the following:
The Internet system has employed a central Internet Assigned Numbers Authority (IANA)[] for the allocation and assignment of various numeric identifiers needed for the operation of the Internet The IANA function is performed by the University of Southern California's Information Sciences Institute The IANA has the discretionary authority to delegate portions
of this responsibility and, with respect to numeric network and autonomous system identifiers, has lodged this responsibility with an Internet Registry (IR)
The NIS manager would become either the IR or a delegate registry authorized by the IR The Internet registration services included the following:
• Network number assignment
• Autonomous system number assignment
• Domain name registration
• Domain name server registrations
From 1993 to 1998, NSI was the only provider of domain name registration services for the .com, net, and org top-level domains, following the Cooperative Agreement with the U.S Government The agreement was amended in 1998, and NSI is now working to develop software supporting a "Shared Registration System" for these top-level domains
Today the U.S Government has begun to privatize the management of domain name space in hopes of introducing competition in order to benefit the global Internet community
Trang 3The Internet Corporation for Assigned Names and Numbers (ICANN)[] is responsible for overseeing this process ICANN is responsible for the registrar accreditation process It also assumes responsibility for certain Internet domain name system functions, as set forth by the U.S Government ICANN is a nonprofit international organization
NIC Support Services
The original solicitation for "Information Services" was granted to General Atomics in April
1993 and was taken away in February 1995 At that time, NSI took over the proposal, and it was renamed NIC Support Services
The goal of the service was to provide a forum for the research and education community, Network Information Centers (NICs) staff, and the academic Internet community, within which the responsibilities of the InterNIC may be defined
Other Internet Registries
With the privatization of registration services came a change in the way IP space and AS numbers are allocated Currently, three Regional Internet Registries (RIRs) provide registration services to all regions around the globe: American Registry for Internet Numbers (ARIN), Reseaux IP Europeens Network Coordination Center (RIPE NCC), and Asian Pacific Network Information Center (APNIC)
ARIN
In late 1997, IANA transferred responsibility for IP number administration from Network Solutions, Inc to ARIN[] ARIN officially opened for operation on October 22, 1997
ARIN is responsible for the allocation of Internet Protocol (IP) numbers in the following geographical areas:
• North America
• South America
• The Caribbean
• Sub-Saharan Africa
ARIN currently manages allocation and registration services for IP numbers, AS numbers, IN-ADDR.ARPA, and IP6.INT inverse mappings They also provide routing registry services where network operators can register, maintain, and retrieve router configuration information and WHOIS services to view specific information associated with a given allocation
ARIN is a nonprofit organization It recovers the costs of administration and management of
IP numbers by charging fees for registration, transfer, maintenance, and membership
RIPE NCC
Created in 1989, RIPE[] is a collaborative organization that consists of European Internet service providers It aims to provide the necessary administration and coordination to enable the operation of the European Internet RIPE acts as an RIR for Europe and surrounding areas
Trang 4RIPE distributes Internet numbers, coordinates the Domain Name System (DNS), and maintains a network management database with information on IP networks, DNS and IP routing policies, and contact information They also provide an Internet software repository, a RIPE document store, routing registry services, and interactive information services
Like ARIN, RIPE is a nonprofit organization and obtains funding from fees associated with its services
APNIC
APNIC[] was created in 1993 and provides registration services similar to ARIN APNIC provides these services to the Asian Pacific region, including 62 countries/regions in South and Central Asia, Southeast Asia, Indochina, and Oceania
APNIC is currently not involved in the administration of DNS services, although it does work with others in the region involved with these services APNIC provides other services, including training and education, policy development, and regional networking activities Notably, APNIC helped found APRICOT (Asian Pacific Regional Internet Conference on Operational Technologies), which is now the premier regional forum for network operators and policy makers
Internet Routing Registries
With the creation of a new breed of ISPs that want to interconnect with one another, offering the required connectivity while maintaining flexibility and control has become more challenging Each provider has a set of rules, or policies, that describe what to accept and what to advertise to all other neighboring networks Sample policies include determining route filtering from a particular ISP and choosing a particular path to a specific destination The potential for various policies from interconnected providers to conflict with and contradict one another is enormous
Internet Routing Registries (IRRs) also serve as a public database for accessing routing contact information used for coordination and troubleshooting
To address these challenges, a neutral routing registry (RR) for each global domain had to be created Each RR maintains a database of routing policies created and updated by each service provider The collection of these different databases is known as the Internet Routing Registry (IRR)
The role of the RR is not to determine policies, but rather to act as a repository for routing policy and administration information This should provide a globally consistent view of all policies used by all providers all over the globe A large number of network operators use routing information obtained from the routing registries to dynamically generate routing policies
Autonomous systems (ASs) use Exterior Gateway Protocols (EGPs) such as BGP to work with one another In complex environments, there should be a formal way of describing and communicating policies between different ASs Maintaining a huge database containing all registered policies for the whole world would be cumbersome and difficult This is why a more distributed approach was created Each RR maintains its own database and must
Trang 5coordinate extensively to achieve consistency between the different databases Here are some
of the different IRR databases in existence today:
• RIPE Routing Registry (European Internet service providers)
• Cable & Wireless Routing Registry (C&W customers)
• CA*net Routing Registry (CA*net customers)
• JPRR Routing Registry (Japanese Internet service providers)
• Routing Arbiter Database (public)
• ARIN Routing Registry (public)
Each of the preceding registries serves a specific service provider's customer base, with the exception of the Routing Arbiter Database (RADB) and ARIN, which provide registration services to anyone As mentioned earlier, the RADB is part of the Routing Arbiter project
Because of the flexibility and benefits of maintaining a local registry, other companies such as Qwest, Level(3), and Verio have developed RRs as well
The Once and Future Internet
Surprisingly enough, although commercialization of the Internet has resulted in a phenomenal rate of growth over the past 10 years, it hasn't hindered innovation Instead, it has inspired it Development of new technologies by the commercial sector, as well as research and educational organizations, is occurring at an astounding rate New technologies can no longer
be immediately deployed in the now "production" Internet; they need to be thoroughly debugged and optimized for realistic conditions Testbeds were created for early adoption of new technologies
Next-Generation Internet Initiative
The federally funded Next-Generation Internet (NGI) Initiative[] is a multiagency U.S federal research and development program that is developing advanced network technologies and revolutionary applications and demonstrating these capabilities on testbeds that are 100 to 1,000 times faster end-to-end than today's Internet
The NGI initiative began October 1, 1997, with the following participating agencies:
• DARPA (Defense Advanced Research Projects Agency)
• DoE (Department of Energy)
• NASA (National Aeronautics and Space Administration)
• NIH (National Institute of Health)
• NIST (National Institute of Standards and Technology)
• NSF (National Science Foundation)
The NGI initiative is managed by individual agency program managers and is coordinated by the Large-Scale Networking Working Group of the Subcommittee on Computing, Information, and Communications (CIC) R&D of the White House National Science and Technology Council's Committee on Technology
Trang 6NGI goals include the following:
• Conduct R&D in advanced end-to-end networking technologies
• Establish and operate two testbeds
• Conduct R&D in revolutionary applications
Conduct R&D in Advanced End-to-End Networking Technologies
The NGI is fostering early deployment of new technologies that will one day be an integral part of the commercial Internet These technologies are focused on enhancing many aspects of computer networking, to include the following:
• Reliability
• Robustness
• Security
• Quality of service/differentiation of service (including multicasting and video)
• Network management (including allocation and sharing of bandwidth)
Establish and Operate Two Testbeds
Ensuring availability of capable testbeds is key to accomplishing the goals of the NGI Two testbeds, referred to loosely as the "100x" testbed and the "1000x" testbed, will be developed for this purpose
The "100x" testbed will connect at least 100 sites—universities, federal research institutions, and other research partners—at speeds 100 times faster end-to-end than today's Internet The testbed will be built on the following federal networks:
• NSF's very high-speed Backbone Network Service (vBNS)
• NASA's Research and Educational Network (NREN)
• DoD's Defense Research and Education Network (DREN)
• DoE's Energy Sciences network (ESnet)
The "1000x" testbed will connect about 10 sites with end-to-end performance at least 1,000 times faster than today's Internet The "1000x" testbed will be built upon DARPA's SuperNet
These testbeds will be used for system-scale testing of advanced technologies and services and for developing and testing advanced applications
Conduct R&D in Revolutionary Applications
NGI research and development will focus on enabling applications and technologies such as these:
• Collaborative technologies
• Digital libraries
• Distributed computing
• Privacy and security
• Remote operation and simulation
Trang 7It will also focus on disciplinary applications such as these:
• Basic science
• Crisis management
• Education
• The environment
• Federal information services
• Health care
• Manufacturing
Internet2
Internet2[] is a project of the University Corporation for Advanced Internet Development (UCAID) It was announced in October 1996 by 34 research universities with a mission of helping to sustain U.S leadership in development, deployment, and operation of next-generation network applications and infrastructure The primary role of Internet2 is to provide focus on fostering the growth of advanced Internet applications and networking protocols that will strengthen the work of universities in their research and education roles With the exponential growth of the Internet, commercial networks controlled by service providers are deploying bandwidth and technologies as rapidly as research and education networks One of the primary goals of Internet2 is to re-create the leading-edge capabilities of testbed networks and then facilitate transfer of these technologies to the global Internet
Internet2 is now a collaborative effort of more than 160 U.S universities in partnership with more than 50 major corporations UCAID's member universities and corporations fund Internet2 Many of the member institutions receive funding through competitively awarded grants from the NSF and other federal agencies participating in the NGI initiative Funding is also made available through other initiatives such as the NSF's Knowledge and Distributed Intelligence (KDI) program
Internet2's goal is not to replace the Internet, but rather to enhance it by making available technologies and experiences developed by Internet2 members Member universities will still require commodity Internet connections from commercial service providers, and utilization of those connections will continue to grow
Abilene
Abilene[] is another project of UCAID It's complementary to Internet2 in the sense that the main goal of Abilene is to provide a primary backbone network for the Internet2 project UCAID, in partnership with Qwest Communications, Nortel Networks, and Cisco Systems, has developed the Abilene network Abilene provides the high-performance interconnect services among the Internet2 regional aggregation points The primarily OC48c (2.5 Gbps) POS (Packet Over SONET) Abilene network became operational in January 1999 and provides OC3 and OC12 access services
Much like the vBNS, Abilene will continually explore emerging Internet technologies, but because of the importance of network stability, Abilene will develop a separate high-performance test network for support of applications that cannot yet be deployed on the leading-edge-but-stable Abilene network Internet2 working groups are in the process of hashing out Abilene deployment details, focusing on native multicast services, optimizing
Trang 8routing configurations and policies, IPv6, and QoS Abilene provides native multicast services and is planning deployment of IPv6 and QoS
Figure 1-8 represents the current Abilene network
Figure 1-8 Abilene Network: Peering Map
Looking Ahead
The decommissioning of the NSFNET in 1995 marked the beginning of a new era The Internet today is a playground for thousands of providers competing for market share Research networks such as Abilene and vBNS are struggling to stay ahead of the curve, as an evolving multibillion-dollar industry continues to exceed all expectations For many businesses and organizations, connecting their networks to the global Internet is no longer a luxury, but a requirement for staying competitive
The structure of the contemporary Internet has implications for service providers and their customers in terms of access speed, reliability, and cost of use Here are some of the questions organizations that want to connect to the Internet should ask:
• Are potential providers (whether established or relatively new to the business) well versed in routing behaviors and architectures?
• How much do customers of providers need to know and do with respect to routing architectures?
Trang 9• Do the customer and provider have a common definition of what constitutes a stable network?
• Is the bandwidth of the access connection the only thing customers need to worry about in order to have the "faster" Internet connection?
The next chapter is intended to help ISPs and their customers evaluate these questions in a basic way Later chapters go into the details of routing architecture
Although interdomain routing has been around for more than a decade, it is still new to everybody, and it continues to evolve every day The rest of this book builds upon this chapter's overview of the structure of the Internet in explaining and demonstrating current routing practices
Frequently Asked Questions
Q—
Are there other NAPs besides the four NSF-awarded NAPs?
A—
Yes As connectivity needs to keep growing, more NAPs are being created Many exchange points are spread over North America, Europe, Asia/Pacific, South America, Africa, and the Middle East
Q—
If I am a customer of a provider, do I have to connect to a NAP?
A—
No NAPs are mainly for interconnections between service providers If you are a customer of
a provider, your connection will be to the provider only However, how your provider is connected to one or more NAPs, or via direct interconnections, can affect the quality of your service
Q—
Is the function of the route server at the NAP to switch traffic between providers?
A—
No The route server keeps a database of routing policies used by providers Providers use the NAP physical media to exchange traffic directly between one another
Q—
Do all providers that connect to a NAP have to peer with the route server?
Trang 10A—
Although this is a recommended procedure, it is not a requirement, and most actually don't
Q—
What is the difference between IRs and IRRs?
A—
Internet Registries (IRs) such as Network Solutions, Inc are responsible for registration services such as registering Internet domain names Internet Routing Registries (IRRs) such as RADB are responsible for maintaining databases of routing policies for service providers
Q—
How are database services different from the Routing Arbiter Databases?
A—
Database services are part of the network information services These databases include communication documents such as RFCs The RADB is a database of routing policies
References
1 http://www.darpa.mil/
2 http://www.nsf.gov/
3 http://www.merit.edu/
4 http://www.ra.net/
5 http://www.isi.edu/
6 http://www.ietf.org/rfc/rfc1786.txt
7 http://www.merit.edu/
8 http://www.ietf.org/
9 http://www.nanog.org/
10 http://www.vbns.net/
11 http://www.internic.net/
12 http://www.iana.org/
13 http://www.icann.org/
14 http://www.arin.net/
15 http://www.ripe.net/
16 http://www.apnic.net/
17 http://www.ngi.gov/
18 http://www.internet2.edu/
19 http://www.internet2.edu/abilene