1 files changed, 227 insertions, 0 deletions
diff --git a/doc/rfc/rfc1517.txt b/doc/rfc/rfc1517.txt
new file mode 100644
index 0000000..3022c92
--- /dev/null
+++ b/doc/rfc/rfc1517.txt
@@ -0,0 +1,227 @@
+
+
+
+
+
+
+Network Working Group                Internet Engineering Steering Group
+Request for Comments: 1517                             R. Hinden, Editor
+Category: Standards Track                                 September 1993
+
+
+           Applicability Statement for the Implementation of
+                 Classless Inter-Domain Routing (CIDR)
+
+Status of this Memo
+
+   This RFC specifies an Internet standards track protocol for the
+   Internet community, and requests discussion and suggestions for
+   improvements.  Please refer to the current edition of the "Internet
+   Official Protocol Standards" for the standardization state and status
+   of this protocol.  Distribution of this memo is unlimited.
+
+1.   Introduction
+
+   As the Internet has evolved and grown in recent years, it has become
+   clear that it will soon face several serious scaling problems. These
+   include:
+
+      - Exhaustion of the class-B network address space. One
+        fundamental cause of this problem is the lack of a network
+        class of a size that is appropriate for a mid-sized
+        organization. Class-C, with a maximum of 254 host addresses, is
+        too small, while class-B, which allows up to 65534 addresses,
+        is too large to be densely populated.  The result is inefficient
+        utilization of class-B network numbers.
+
+      - Routing information overload. The size and rate of growth of the
+        routing tables in Internet routers is beyond the ability of
+        current software (and people) to effectively manage.
+
+      - Eventual exhaustion of IP network numbers.
+
+   It has become clear that the first two of these problems are likely
+   to become critical in the near term.  Classless Inter-Domain Routing
+   (CIDR) ttempts to deal with these problems by defining a mechanism to
+   slow the growth of routing tables and reduce the need to allocate new
+   IP network numbers.  It does not attempt to solve the third problem,
+   which is of a more long-term nature, but instead endeavors to ease
+   enough of the short to mid-term difficulties to allow the Internet to
+   continue to function efficiently while progress is made on a longer-
+   term solution.
+
+   The IESG, after a thorough discussion in the IETF, in June 1992
+   selected CIDR as the solution for the short term routing table
+
+
+
+IESG                                                            [Page 1]
+
+RFC 1517              CIDR Applicability Statement        September 1993
+
+
+   explosion problem [1].
+
+2. Components of the Architecture
+
+   The CIDR architecture is described in the following documents:
+
+      - "An Architecture for IP Address Allocation with CIDR" [2]
+
+      - "Classless Inter-Domain Routing (CIDR):  An Address Assignment
+        and Aggregation Strategy" [3]
+
+   The first of these documents presents the overall architecture of
+   CIDR; the second describes the specific address allocation scheme to
+   be used.
+
+   In addition to these two documents, "Guidelines for Management of IP
+   Address Space" [4] provides specific recommendations for assigning IP
+   addresses that are consistent with [2] and [3], and "Status of CIDR
+   Deployment in the Internet" [5] describes the timetable for deploying
+   [4] in the Internet.  Both [4] and [5] should be viewed as
+   supporting, rather than defining, documents.
+
+   In addition to the documents mentioned above, CIDR requires that
+   inter-domain routing protocols be capable of handling reachability
+   information that is expressed solely in terms of IP address prefixes.
+   While several inter-domain routing protocols are capable of
+   supporting such functionality, this Applicability Statement does not
+   mandate the use of a particular one.
+
+   Although Internet routing domains are not required to use routing
+   protocols capable of propagating CIDR routes, the topology such
+   routing domains can support will be somewhat limited.  In particular,
+   the non-CIDR-capable parts of the Internet will need to default
+   towards the CIDR-capable parts of the Internet for routes which have
+   been aggregated to non-network boundaries.
+
+3. Applicability of CIDR
+
+   The CIDR architecture is applicable to any group of connected domains
+   that supports IP version 4 [6] [7].  CIDR does not require all of the
+   domains in the Internet to be converted to use CIDR. It assumes that
+   some of the existing domains in the Internet will never be able to
+   convert.  Despite this, CIDR will still provide connectivity to such
+   places, although the optimality of routes to these places may be
+   impacted.
+
+   This Applicability Statement requires Internet domains providing
+   backbone and/or transit service to fully implement CIDR in order to
+
+
+
+IESG                                                            [Page 2]
+
+RFC 1517              CIDR Applicability Statement        September 1993
+
+
+   ensure that the growth of the resources required by routers to
+   provide Internet-wide connectivity will be significantly slower than
+   the growth of the number of assigned networks.
+
+   This Applicability Statement strongly recommends that all non-
+   backbone/transit Internet domains also implement CIDR because it will
+   reduce the amount of routing information inside of these domains.
+
+   Individual domains are free to choose whatever inter-domain and
+   intra-domain routing architectures best meet their requirements.
+   Specifically, this Applicability Statement does not prevent a domain
+   or a group of domains from using addressing schemes which do not
+   conform to CIDR.  Subject to the available resources in routers, CIDR
+   should be able to co-exist with other addressing schemes without
+   adversely impacting overall connectivity.
+
+4. References
+
+   [1] Gross, P., and P. Almquist, "IESG Deliberations on Routing and
+       Addressing", RFC 1380, IESG Chair, IESG Internet AD, November
+       1992.
+
+   [2] Rekhter, Y., and T. Li, "An Architecture for IP Address
+       Allocation with CIDR", RFC 1518, T.J. Watson Research Center, IBM
+       Corp., cisco Systems, September 1993.
+
+   [3] Fuller, V., Li, T., Yu, J., and K. Varadhan, "Classless Inter-
+       Domain Routing (CIDR): An Address Assignment and Aggregation
+       Strategy", RFC 1519, BARRNet, cisco, Merit, and OARnet, September
+       1993.
+
+   [4] Gerich, E., "Guidelines for Management of IP Address Space", RFC
+       1466, Merit, May 1993.
+
+   [5] Topolcic, C., "Status of CIDR Deployment in the Internet", RFC
+       1467, CNRI, August 1993.
+
+   [6] Postel, J., "Internet Protocol - DARPA Internet Program Protocol
+       Specification", STD 5, RFC 791, USC/Information Sciences
+       Institute, September 1981.
+
+   [7] Braden, R., Editor, "Requirements for Internet Hosts --
+       Communication Layers", STD 3, RFC 1122, IETF, October 1989.
+
+5. Security Considerations
+
+   Security issues are not discussed in this memo.
+
+
+
+
+IESG                                                            [Page 3]
+
+RFC 1517              CIDR Applicability Statement        September 1993
+
+
+6. Author's Address
+
+   Robert M. Hinden
+   Sun Microsystems
+   2550 Garcia Ave, MS MTV5-44
+   Mt. View, CA 94043
+
+   Phone: (415) 336-2082
+   Fax:   (415) 336-6015
+
+   EMail: hinden@eng.sun.com
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+IESG                                                            [Page 4]
+
+\ No newline at end of file