Network Working Group J. Chroboczek
Internet-Draft IRIF, University of Paris-Diderot
Intended status: Informational January 5, 2017
Expires: July 9, 2017
Applicability of the Babel routing protocol
draft-ietf-babel-applicability-01
Abstract
This document describes some application areas where the Babel
routing protocol (RFC 6126) has been found to be useful.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Existing successful deployments of Babel . . . . . . . . . . 2
2.1. Hybrid networks . . . . . . . . . . . . . . . . . . . . . 2
2.2. Large scale overlay networks . . . . . . . . . . . . . . 2
2.3. Pure mesh networks . . . . . . . . . . . . . . . . . . . 3
2.4. Small unmanaged networks . . . . . . . . . . . . . . . . 3
3. Application Areas where Babel is not recommended . . . . . . 3
3.1. Large, stable networks . . . . . . . . . . . . . . . . . 3
3.2. Low-power and constrained networks . . . . . . . . . . . 3
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3
5. Security Considerations . . . . . . . . . . . . . . . . . . . 3
6. Informational References . . . . . . . . . . . . . . . . . . 4
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 5
1. Introduction
Babel [RFC6126] is a loop-avoiding distance-vector routing protocol
that aims to be robust in a variety of environments.
This document describes a few areas where Babel has been found to be
useful. It is structured as follows. In Section 2, we describe
application areas where Babel has been successfully deployed, and in
Section 3, we describe application areas where deployment of Babel is
not encouraged because better alternatives are available.
2. Existing successful deployments of Babel
2.1. Hybrid networks
Babel is able to deal with both classical, prefix-based ("Internet-
style") routing and flat ("mesh-style") routing over non-transitive
link technologies. Because of that, it has seen a number of
succesful deployments in medium-sized hybrid networks, networks that
combine a wired, aggregated backbone with meshy wireless bits at the
edges. No other routing protocol known to us is similarly robust and
efficient in this particular type of network.
2.2. Large scale overlay networks
The algorithms used by Babel (loop avoidance, hysteresis, delayed
updates) allow it to remain stable and efficient in the presence of
unstable metrics, even in the presence of a feedback loop. For this
reason, it has been successfully deployed in large scale overlay
networks, built out of thousands of tunnels spanning continents,
where it is used with a metric computed from links' latencies
[DELAY-BASED].
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2.3. Pure mesh networks
Babel has been repeatedly shown to be competitive with dedicated
routing protocols for wireless mesh networks [REAL-WORLD]
[BRIDGING-LAYERS]. While this particular niche is already served by
a number of mature protocols, notably OLSR-ETX and OLSRv2 [RFC7181]
equipped with the DAT metric [RFC7779], Babel has seen a moderate
amount of successful deployment in pure mesh networks.
2.4. Small unmanaged networks
Because of its small size and simple configuration, Babel has been
deployed in small, unmanaged networks (three to five routers), where
it serves as a more efficient replacement for RIP [RFC2453], with the
significant advantage of having good support for wireless links.
3. Application Areas where Babel is not recommended
There exist application areas where Babel is a poor fit.
3.1. Large, stable networks
Babel relies on periodic updates, and even in a stable network, it
generates a constant amount of background traffic. In large, stable,
well-administered networks, it is preferable to use protocols layered
above a reliable transport mechanism, such as OSPF [RFC5340], EIGRP
[RFC7868] or IS-IS [RFC1195].
3.2. Low-power and constrained networks
Babel relies on periodic updates and maintains within each node an
amount of state that is proportional to the number of reachable
destinations. In networks containing resource-constrained or
exteremely low-power nodes, it may be preferable to use a protocol
that limits the amount of state maintained and propagated; we have
heard of AODVv2 [AODVv2], RPL [RFC6550] and LOADng [LOADng].
4. IANA Considerations
This document requires no IANA actions. [RFC Editor: please remove
this section before publication.]
5. Security Considerations
As in all distance-vector routing protocols, a Babel speaker receives
reachability information from its neighbours, which by default is
trusted. A number of attacks are possible if this information is not
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suitably protected, either by a lower-layer mechanism or by an
extension to the protocol itself (e.g. [RFC7298]).
Implementors and deployers must be aware of the insecure nature of
the base protocol, and must take suitable measures to ensure that the
protocol is deployed as securely as required by the application.
6. Informational References
[AODVv2] Perkins, C., Ratliff, S., Dowdell, J., Steenbrink, L., and
V. Mercieca, "Ad Hoc On-demand Distance Vector Version 2
(AODVv2) Routing", draft-ietf-manet-aodvv2-16 (work in
progress), May 2016.
[BRIDGING-LAYERS]
Murray, D., Dixon, M., and T. Koziniec, "An Experimental
Comparison of Routing Protocols in Multi Hop Ad Hoc
Networks", Proc. ATNAC 2010, 2010.
[DELAY-BASED]
Jonglez, B. and J. Chroboczek, "A delay-based routing
metric", March 2014, <http://arxiv.org/abs/1403.3488>.
[LOADng] Clausen, T., Verdiere, A., Yi, J., Niktash, A., Igarashi,
Y., Satoh, H., Herberg, U., Lavenu, C., Lys, T., and J.
Dean, "The Lightweight On-demand Ad hoc Distance-vector
Routing Protocol - Next Generation (LOADng)", draft-
clausen-lln-loadng-15 (work in progress), January 2017.
[REAL-WORLD]
Abolhasan, M., Hagelstein, B., and J. Wang, "Real-world
performance of current proactive multi-hop mesh
protocols", Asia-Pacific Conference on Communication 2009,
2009.
[RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
dual environments", RFC 1195, December 1990.
[RFC2453] Malkin, G., "RIP Version 2", STD 56, RFC 2453, November
1998.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
for IPv6", RFC 5340, July 2008.
[RFC6126] Chroboczek, J., "The Babel Routing Protocol", RFC 6126,
February 2011.
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[RFC6550] Winter, T., Ed., Thubert, P., Ed., Brandt, A., Hui, J.,
Kelsey, R., Levis, P., Pister, K., Struik, R., Vasseur,
JP., and R. Alexander, "RPL: IPv6 Routing Protocol for
Low-Power and Lossy Networks", RFC 6550, March 2012.
[RFC7181] Clausen, T., Dearlove, C., Jacquet, P., and U. Herberg,
"The Optimized Link State Routing Protocol Version 2",
RFC 7181, April 2014.
[RFC7298] Ovsienko, D., "Babel Hashed Message Authentication Code
(HMAC) Cryptographic Authentication", RFC 7298,
DOI 10.17487/RFC7298, July 2014,
<http://www.rfc-editor.org/info/rfc7298>.
[RFC7779] Rogge, H. and E. Baccelli, "Directional Airtime Metric
Based on Packet Sequence Numbers for Optimized Link State
Routing Version 2 (OLSRv2)", RFC 7779,
DOI 10.17487/RFC7779, April 2016.
[RFC7868] Savage, D., Ng, J., Moore, S., Slice, D., Paluch, P., and
R. White, "Cisco's Enhanced Interior Gateway Routing
Protocol (EIGRP)", RFC 7868, DOI 10.17487/RFC7868, May
2016.
Author's Address
Juliusz Chroboczek
IRIF, University of Paris-Diderot
Case 7014
75205 Paris Cedex 13
France
Email: jch@irif.fr
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