zerouter BoF Problem Statement

1
zerouter BoFProblem Statement

• 19th Nov 2002
• 55th IETF - Atlanta, Georgia, USA
• aidan.williams_at_motorola.com

2
Problem space

• Main goal self-configuring routers
  forun-administered networks

3
L2 vs L3

• IP routing has advantages vs L2 bridging in the
  home/SOHO space
• efficient forwarding
• works with non-802 addressed networks (1394, BT)
• Fragmentation and PMTU discovery
• Fail safe(r)
• Commodity L2 bridges often lack 802.1d spanning
  tree
• However
• IP subnet address assignment is manual
• IP routing protocols currently need to be
  configured

4
Proposal

• Develop zeroconf routing solutions that
• automatically configure IP addressing
• automatically configure unicast IP forwarding
• automatically configure multicast IP forwarding
• detect and recover from inevitable addressing
  collisions

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Unicast Approaches

• Approaches for automatic unicast configuration
• decentralised subnet assignment
• routers use a distributed protocol for choosing a
  subnet identifier from an available pool
• multi-link subnets
• multiple links are bridged together at the IP
  layer
• only one IP subnet is necessary
• ripple out explicit configuration
• a centralised server allocates subnets/addresses
  for a network
• or, allow sub-delegation to ripple out

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Multicast

• Bootstrap from working unicast addressing and
  routing
• Zerouter protocols dont introduce any new issues

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Scope comments

• In scope
• IPv4 and IPv6 solutions
• solutions for 10s of links
• Out of scope
• Development of new prefix delegation protocols
• Auto-configuration of arbitrary router
  parameters(L2 media options, etc)
• Auto-configuration of transit networks
• Automatic configuration of services(e.g. DNS,
  SLP, etc)