CIDR
CIDR (Classless Inter-Domain Routing) and aggregation
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CIDR RFCs (17)
RFC 7608: BCP 198: IPv6 Prefix Length Recommendation for Forwarding
Best Current Practice- M. Boucadair
- A. Petrescu
- F. Baker
- July 2015
- IETF publication
- Operations and Management Area
Abstract
IPv6 prefix length, as in IPv4, is a parameter conveyed and used in IPv6 routing and forwarding processes in accordance with the Classless Inter-domain Routing (CIDR) architecture. The length of an IPv6 prefix may be any number from zero to 128, although subnets using stateless address autoconfiguration (SLAAC) for address allocation conventionally use a /64 prefix. Hardware and software implementations of routing and forwarding should therefore impose no rules on prefix length, but implement longest-match-first on prefixes of any valid length.
Abstract
IPv6 prefix length, as in IPv4, is a parameter conveyed and used in IPv6 routing and forwarding processes in accordance with the Classless Inter-domain Routing (CIDR) architecture. The length of an IPv6 prefix may be any number from zero to 128, although subnets using stateless address autoconfiguration (SLAAC) for address allocation conventionally use a /64 prefix. Hardware and software implementations of routing and forwarding should therefore impose no rules on prefix length, but implement longest-match-first on prefixes of any valid length.
RFC 4632: BCP 122: Classless Inter-domain Routing (CIDR): The Internet Address Assignment and Aggregation Plan
Best Current Practice- V. Fuller
- T. Li
- August 2006
- IETF publication
- Operations and Management Area
Abstract
This memo discusses the strategy for address assignment of the existing 32-bit IPv4 address space with a view toward conserving the address space and limiting the growth rate of global routing state. This document obsoletes the original Classless Inter-domain Routing (CIDR) spec in RFC 1519, with changes made both to clarify the concepts it introduced and, after more than twelve years, to update the Internet community on the results of deploying the technology described. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
Abstract
This memo discusses the strategy for address assignment of the existing 32-bit IPv4 address space with a view toward conserving the address space and limiting the growth rate of global routing state. This document obsoletes the original Classless Inter-domain Routing (CIDR) spec in RFC 1519, with changes made both to clarify the concepts it introduced and, after more than twelve years, to update the Internet community on the results of deploying the technology described. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC 2519: A Framework for Inter-Domain Route Aggregation
Informational- E. Chen
- J. Stewart
- February 1999
- IETF publication
- Routing Area
Abstract
This document presents a framework for inter-domain route aggregation and shows an example router configuration which 'implements' this framework. This memo provides information for the Internet community
Abstract
This document presents a framework for inter-domain route aggregation and shows an example router configuration which 'implements' this framework. This memo provides information for the Internet community
RFC 2008: BCP 7: Implications of Various Address Allocation Policies for Internet Routing
Best Current Practice- Y. Rekhter
- T. Li
- October 1996
- IETF publication
- Operational Requirements Area
Abstract
The purpose of this document is to articulate certain relevant fundamental technical issues that must be considered in formulating unicast address allocation and management policies for the Public Internet, and to provide recommendations with respect to these policies. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
Abstract
The purpose of this document is to articulate certain relevant fundamental technical issues that must be considered in formulating unicast address allocation and management policies for the Public Internet, and to provide recommendations with respect to these policies. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC 2036: Observations on the use of Components of the Class A Address Space within the Internet
Historic- G. Huston
- October 1996
- IETF publication
- Operational Requirements Area
Abstract
This document is a commentary on the recommendation that IANA commence allocation of the presently unallocated components of the Class A address space to registries, for deployment within the Internet as class-less address blocks. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
Abstract
This document is a commentary on the recommendation that IANA commence allocation of the presently unallocated components of the Class A address space to registries, for deployment within the Internet as class-less address blocks. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
RFC 1917: BCP 4: An Appeal to the Internet Community to Return Unused IP Networks (Prefixes) to the IANA
Best Current Practice- P. Nesser II
- February 1996
- IETF publication
- Operational Requirements Area
Abstract
This document is an appeal to the Internet community to return unused address space, i.e. any block of consecutive IP prefixes, to the Internet Assigned Numbers Authority (IANA) or any of the delegated registries, for reapportionment. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
Abstract
This document is an appeal to the Internet community to return unused address space, i.e. any block of consecutive IP prefixes, to the Internet Assigned Numbers Authority (IANA) or any of the delegated registries, for reapportionment. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC 1918: BCP 5: Address Allocation for Private Internets
Best Current Practice- Y. Rekhter
- B. Moskowitz
- D. Karrenberg
- G. J. de Groot
- E. Lear
- February 1996
- IETF publication
- Operational Requirements Area
Abstract
This document describes address allocation for private internets. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
Abstract
This document describes address allocation for private internets. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
RFC 1817: CIDR and Classful Routing
Historic- Y. Rekhter
- August 1995
- Legacy publication
Abstract
This document represents the IAB's (Internet Architecture Board) evaluation of the current and near term implications of CIDR on organizations that use Classful routing technology. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
Abstract
This document represents the IAB's (Internet Architecture Board) evaluation of the current and near term implications of CIDR on organizations that use Classful routing technology. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
RFC 1517: Applicability Statement for the Implementation of Classless Inter-Domain Routing (CIDR)
Historic- Internet Engineering Steering Group
- R. Hinden
- September 1993
- IETF publication
Abstract
Classless Inter-Domain Routing (CIDR) defines a mechanism to slow the growth of routing tables and reduce the need to allocate new IP network numbers. [STANDARDS-TRACK]
Abstract
Classless Inter-Domain Routing (CIDR) defines a mechanism to slow the growth of routing tables and reduce the need to allocate new IP network numbers. [STANDARDS-TRACK]
RFC 1518: An Architecture for IP Address Allocation with CIDR
Historic- Y. Rekhter
- T. Li
- September 1993
- Legacy publication
Abstract
This paper provides an architecture and a plan for allocating IP addresses in the Internet. This architecture and the plan are intended to play an important role in steering the Internet towards the Address Assignment and Aggregating Strategy. [STANDARDS-TRACK]
Abstract
This paper provides an architecture and a plan for allocating IP addresses in the Internet. This architecture and the plan are intended to play an important role in steering the Internet towards the Address Assignment and Aggregating Strategy. [STANDARDS-TRACK]
RFC 1519: Classless Inter-Domain Routing (CIDR): an Address Assignment and Aggregation Strategy
Proposed Standard- V. Fuller
- T. Li
- J. Yu
- K. Varadhan
- September 1993
- Legacy publication
Abstract
This memo discusses strategies for address assignment of the existing IP address space with a view to conserve the address space and stem the explosive growth of routing tables in default-route-free routers. [STANDARDS-TRACK]
Obsoleted by RFC 4632
Abstract
This memo discusses strategies for address assignment of the existing IP address space with a view to conserve the address space and stem the explosive growth of routing tables in default-route-free routers. [STANDARDS-TRACK]
RFC 1520: Exchanging Routing Information Across Provider Boundaries in the CIDR Environment
Historic- Y. Rekhter
- C. Topolcic
- September 1993
- Legacy publication
Abstract
The purpose of this document is twofold. First, it describes various alternatives for exchanging inter-domain routing information across domain boundaries, where one of the peering domain is CIDR-capable and another is not. Second, it addresses the implications of running CIDR- capable inter-domain routing protocols (e.g., BGP-4, IDRP) on intra- domain routing. This memo provides information for the Internet community. It does not specify an Internet standard.
Abstract
The purpose of this document is twofold. First, it describes various alternatives for exchanging inter-domain routing information across domain boundaries, where one of the peering domain is CIDR-capable and another is not. Second, it addresses the implications of running CIDR- capable inter-domain routing protocols (e.g., BGP-4, IDRP) on intra- domain routing. This memo provides information for the Internet community. It does not specify an Internet standard.
RFC 1467: Status of CIDR Deployment in the Internet
Historic- C. Topolcic
- August 1993
- Legacy publication
Abstract
This document describes the current status of the development and deployment of CIDR technology into the Internet. This document replaces RFC 1367, which was a schedule for the deployment of IP address space management procedures to support route aggregation. This memo provides information for the Internet community. It does not specify an Internet standard.
Abstract
This document describes the current status of the development and deployment of CIDR technology into the Internet. This document replaces RFC 1367, which was a schedule for the deployment of IP address space management procedures to support route aggregation. This memo provides information for the Internet community. It does not specify an Internet standard.
RFC 1481: IAB Recommendation for an Intermediate Strategy to Address the Issue of Scaling
Historic- C. Huitema
- July 1993
- Legacy publication
Abstract
CIDR is proposed as an immediate term strategy to extend the life of the current 32 bit IP address space. This memo provides information for the Internet community. It does not specify an Internet standard.
Abstract
CIDR is proposed as an immediate term strategy to extend the life of the current 32 bit IP address space. This memo provides information for the Internet community. It does not specify an Internet standard.
RFC 1482: Aggregation Support in the NSFNET Policy-Based Routing Database
Historic- M. Knopper
- S. Richardson
- June 1993
- IETF publication
- Operational Requirements Area
Abstract
This document describes plans for support of route aggregation, as specified in the descriptions of Classless Inter-Domain Routing (CIDR) [1] and the BGP-4 protocol [2], by the NSFNET Backbone Network Service. This memo provides information for the Internet community. It does not specify an Internet standard.
Abstract
This document describes plans for support of route aggregation, as specified in the descriptions of Classless Inter-Domain Routing (CIDR) [1] and the BGP-4 protocol [2], by the NSFNET Backbone Network Service. This memo provides information for the Internet community. It does not specify an Internet standard.
RFC 1466: Guidelines for Management of IP Address Space
Informational- E. Gerich
- May 1993
- Legacy publication
Abstract
This document proposes a plan which will forward the implementation of RFC 1174 and which defines the allocation and assignment of the network number space. This memo provides information for the Internet community. It does not specify an Internet standard.
Obsoleted by RFC 2050
Abstract
This document proposes a plan which will forward the implementation of RFC 1174 and which defines the allocation and assignment of the network number space. This memo provides information for the Internet community. It does not specify an Internet standard.
RFC 1338: Supernetting: an Address Assignment and Aggregation Strategy
Informational- V. Fuller
- T. Li
- J. Yu
- K. Varadhan
- June 1992
- Legacy publication
Abstract
This memo discusses strategies for address assignment of the existing IP address space with a view to conserve the address space and stem the explosive growth of routing tables in default-route-free routers run by transit routing domain providers. This memo provides information for the Internet community. It does not specify an Internet standard.
Obsoleted by RFC 1519
Abstract
This memo discusses strategies for address assignment of the existing IP address space with a view to conserve the address space and stem the explosive growth of routing tables in default-route-free routers run by transit routing domain providers. This memo provides information for the Internet community. It does not specify an Internet standard.
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