Use of OSPF-MDR in Single-Hop Broadcast Networks
RFC 7038
Document | Type |
RFC - Experimental
(October 2013; No errata)
Updates RFC 5614
|
|
---|---|---|---|
Author | Richard Ogier | ||
Last updated | 2015-10-14 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | WG Document | |
Document shepherd | Acee Lindem | ||
Shepherd write-up | Show (last changed 2013-06-04) | ||
IESG | IESG state | RFC 7038 (Experimental) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Stewart Bryant | ||
Send notices to | (None) | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | No IANA Actions |
Internet Engineering Task Force (IETF) R. Ogier Request for Comments: 7038 SRI International Updates: 5614 October 2013 Category: Experimental ISSN: 2070-1721 Use of OSPF-MDR in Single-Hop Broadcast Networks Abstract RFC 5614 (OSPF-MDR) extends OSPF to support mobile ad hoc networks (MANETs) by specifying its operation on the new OSPF interface of type MANET. This document describes the use of OSPF-MDR (MANET Designated Router) in a single-hop broadcast network, which is a special case of a MANET in which each router is a (one-hop) neighbor of each other router. Unlike an OSPF broadcast interface, such an interface can have a different cost associated with each neighbor. The document includes configuration recommendations and simplified mechanisms that can be used in single-hop broadcast networks. Status of This Memo This document is not an Internet Standards Track specification; it is published for examination, experimental implementation, and evaluation. This document defines an Experimental Protocol for the Internet community. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7038. Ogier Experimental [Page 1] RFC 7038 OSPF-MDR in Single-Hop Broadcast Networks October 2013 Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. 1. Introduction OSPF-MDR [RFC5614] specifies an extension of OSPF [RFC2328, RFC5340] to support mobile ad hoc networks (MANETs) by specifying its operation on the new OSPF interface of type MANET. OSPF-MDR generalizes the Designated Router (DR) to a connected dominating set (CDS) consisting of a typically small subset of routers called MANET Designated Routers (MDRs). Similarly, the Backup Designated Router (BDR) is generalized to a subset of routers called Backup MDRs (BMDRs). MDRs achieve scalability in MANETs similar to the way DRs achieve scalability in broadcast networks: o MDRs have primary responsibility for flooding the Link State Advertisements (LSAs). Backup MDRs provide backup flooding when MDRs temporarily fail. o MDRs allow the number of adjacencies to be dramatically reduced by requiring adjacencies to be formed only between MDR/BMDR routers and their neighbors. In addition, OSPF-MDR has the following features: o MDRs and BMDRs are elected based on information obtained from modified Hello packets received from neighbors. o If adjacency reduction is used (the default), adjacencies are formed between MDRs so as to form a connected subgraph. An option (AdjConnectivity = 2) allows for additional adjacencies to be formed between MDRs/BMDRs to produce a biconnected subgraph. o Each non-MDR router becomes adjacent with an MDR called its Parent, and optionally (if AdjConnectivity = 2) becomes adjacent with another MDR or BMDR called its Backup Parent. Ogier Experimental [Page 2] RFC 7038 OSPF-MDR in Single-Hop Broadcast Networks October 2013 o Each router advertises connections to its neighbor routers as point-to-point links in its router-LSA. Network-LSAs are not used. o In addition to full-topology LSAs, partial-topology LSAs may be used to reduce the size of router-LSAs. Such LSAs are formatted as standard LSAs, but advertise links to only a subset of neighbors. o Optionally, differential Hellos can be used, which reduce overhead by reporting only changes in neighbor states. This document describes the use of OSPF-MDR in a single-hop broadcast network, which is a special case of a MANET in which each router is aShow full document text