Routing for Sensor Networks

1
Routing for Low Power and Lossy Networks
(RL2N) BOF IETF-70 - Vancouver - December
2007 BOF Chairs JP Vasseur/David
Culler ADs Dave Ward/Ross Callon
2
Agenda

• Administrativia (Chairs, 5 min)
• Notes takers
• Agenda bashing
• Scoping the BOF (Chairs/ADs, 10 min)
• Motivation and problem statement presentation
• Summary of the discussions on rsn_at_ietf.org and
  consensus so far
• Summary of pre-WG meeting Nov 15 - Boston
• RL2N Routing Requirements summary (several
  chairs, 20mn)
• Routing requirements for L2Ns and Protocol survey
  (Phil - 10mn)
• RL2N WG Charter discussion (10 mn)
• Work Items/Milestones
• Interaction with other WG (6lowpan)
• What's in/out scope?
• Conclusion and next steps (5mn, chairs and ADs)

3
BOF scoping - Motivation and Problem statement

• L2Ns Networks comprising a large number of
  highly constrained devices interconnected by
  wireless links of unpredictable quality
• More details in the L2Ns presentation made during
  the Routing Area Meeting in Chicago
• A few important facts to remind
• This is not a research area
• L2Ns are being deployed today using non IP
  solutions
• The problem space is well understood and
  practical experience
• The number of proprietary protocol literarily
  explodes
• There is already an IETF WG (6lowpan) that has
  produced v6 header compression RFC for v6 over
  IEEE 802.15.4 - A IP routing solution is required.

4
BOF scoping - Motivation and Problem statement

• A solvable problem ? Yes this is a focused
  effort.
• The goal is not to find a routing solution for
  all types of L2Ns
• We will focus on a few key use case for which
• There are non-IP/proprietary deployments,
• We have a clear understanding on the
  requirements,
• We have the right set of people engaged and
  committed to produce a solution

5
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

6
BOF scoping - Summary of discussions

• Pre-WG meeting was held in Boston on November 15
• Participants K. Pister (Dust), R. King
  (Crossbow), A. Brandt (Zensys), M. A. Mc Lachlan
  (BT), P. Levis (Stanford), J. Oliveira (Drexel),
  J. Butler (Cimetrics), M. Dohler (FT) M.
  Murphy-hoye (Intel), Ed Butler (Intel), David
  Culler (Arch Roc), G. Mulligan (6lowpan
  co-chair), JP Vasseur (Cisco).
• RTG AD Dave Ward attended.
• Agenda

Introduction and Background JP/David -
15mn Review of the current IDs (15mn per ID)
- draft-brandt-rl2n-home-routing-reqs-01-
Anders - draft-pister-rl2n-industrial-routin
g-reqs-01- Kris - draft-levis-rl2n-overview-
protocols-01 - Phil Charter Discussion of
the proposed charter Interaction with other
WGs 6lowpan and SDOs Open issues DTN,
MANET BOF organization
7
RL2N Routing Requirements summary

• There has been good discussion on these documents
• That said, still not mature and further
  discussion is nedeed
• This is just a very high level overview

8
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

9
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

10
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

11
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

12
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

13
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

14
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

15
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

16
BOF scoping - Summary of discussions

• The informal work started about a year ago
• Creation of a non-WG mailing list (rsn_at_ietf.org -
  200 subscribers)
• Some on-line discussions
• Lots of off-line discussions
• We started with a generic requirements ID (used
  as a repository) draft-culler-rl2n-routing-reqs
• Moving to an application driven routing
  requirements approach
• Industrial draft-pister-rl2n-indus-routing-reqs
• Connected Home draft-brandt-rl2n-home-routing-req
  s
• Smart Cities to be posted.

17
What are L2Ns ?

• L2Ns Networks comprising a large number of
  highly constrained devices interconnected by
  wireless links of unpredictable quality

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Why are L2Ns so important This is Obvious
(Ross)
Energy Saving (I2E)
Improve Productivity
Preventing Failures
Enhance Safety Security
Enable New Knowledge
High-Confidence Transport
Improve Food H20
Smart Home
Healthcare
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Is there a problem here ?

• So what?
• New class of applications
• New tier of devices
• Networks move the bits
• Can we just consider L2Ns as regular IP
  networks and use existing protocols ?

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What make L2Ns so special ?

• L2Ns
• An order of magnitude larger in term of number of
  nodes,
• Links are highly unstable and Nodes die much more
  often,
• Unique requirements (see next slides)

• Current Internet
• An IGP has typically few hundreds of nodes,
• Links and nodes are stable,
• Nodes constraints or link bandwidth are typically
  non issues.

21
Unique Routing Requirements L2Ns
Routing in L2Ns is a MUST for energy saving
(short distances less energy to transmit)
and to route around obstacles (including poor
quality links),

• Highly constrained devices
• Harsh dynamic environments (variable link
  qualities, link/nodes fail at a rate
  significantly higher than within the Internet)
• Small MTU (high error rate, limited buffer/bw)
• Constraint routing is a MUST take into account
  link and nodes properties and constraints (also
  unusual)

22
Unique Routing Requirements L2Ns (Cont)

• Deep power management WSN in sleep mode most of
  the time
• Highly heterogeneous capabilities
• Structured traffic patterns P2MP, MP2P but also
  more and more P2P

23
Unique Routing Requirements L2Ns (Cont)

• Multi-path and asymmetrical load balancing
• Data aware routing data aggregation along a
  dynamically computed path to a sink.
• Self-Managed !!

24
Why cant we use an existing routing protocol ?

• Many IP routing protocols have been designed
  RIP, OSPF, AODV, OLSR, DYMO, TBRPF
• But
• As pointed out Routing requirements for L2Ns are
  unique,
• None of them satisfy the minimum set of
  requirements,
• Some of them could be adapted/twisted/ but that
  means major protocol rework.

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What about MANEMO ?

• Problem Mobile Ad-Hoc NEMO, enable a L3 mesh of
  NEMO mobile routers that optimizes local and
  global reachability.
• Quite different problem spaces. There are
  commonalities but also lots of differences (level
  of constraints, P2P, ),
• May lead to common routing protocol solutions,
• RSN could be fed by MANEMO requirements and see
  whether the protocol designed for L2Ns could be
  accommodated (WITHOUT losing the focus).

26
Suggested approach do not design solutions for
all L2Ns

• Research has focused on near-optimal solutions to
  the specific problems
• IP is maximizing interoperability, not aiming at
  finding a local optimum -)

27
Standardization status
New applications pretty much every day but

• The number of proprietary solutions literally
  explodes Zigbee, Z-Wave, Xmesh, SmartMesh/TSMP,
  SP100, ) at many layers (physical, MAC, L3) and
  most chip vendor claim to be compatible with
  their own standard
• Various protocol (L1/L2) to be reused such as
  802.11, 802.15.4, WiMax,

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So what are the options ?
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Do Nothing
Honeywell
Wireless HART
TrueMesh
Znet
ISA SP100.11a
Internet
Smartmesh
MintRoute
Xmesh
MultiHop LQI
CENS Route
TinyAODV
L2N
L2N
What the Internet will soon look like
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• Issues ?

L2N
L2N
L2N
L2N
Internet
L2N
Multi-protocol Gateway (IP-proxy, protocol
translations)
L2N
L2N
L2N
We know all of this from the 80 and 90
Management complexity Lack of end to end
consistency in term of routing, QoS, management,
security, Remember SNA, IPX, Vines, or IP
over ATM/FR, ?
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Or IP end to end
L2N
L2N
L2N
L2N
Internet
L2N
L2N
IP router !
L2N
L2N
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IETF Standardization status

• 6LoWPAN (to be re-chartered soon to extend the
  scope and work on discovery, management,
  security, )
• 6LoWPAN WG consensus (today) L2/L3 agnostic
  requirements to be worked within 6lowpan and
  potentially given to RL2N.
• RL2N (Routing for Low Power and Lossy Networks)
  new mailing list where the routing issues are
  discussed. Several large players have joined the
  initiative https//www1.ietf.org/mailman/listinfo
  /rsn

33
IETF Standardization status

• In the works
• Routing Requirements for L2Ns draft-culler-rl2n-r
  outing-reqs-01
• Routing Requirement ID for Connected Home
  draft-brandt-rl2n-home routing-reqs
• Routing Requirements ID for Industrial
  applications in the works
• Survey on existing routing protocol
  applicability draft-levis-rl2n-overview-protocols
  
• Routing metrics for RL2N in the works

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Key take-away

• Stating Facts
• L2Ns are being deployed using proprietary
  protocols the need is there.
• L2Ns routing requirements are unique.
• So
• Does the IETF community agree that we should be
  having a WG focusing on routing issues for L2Ns ?
  

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• Thanks.