2. IPCN - Thierry Ernst - May 2001 1 Mobile Routers in IPv6 Thierry Ernst - MOTOROLA Labs & INRIA (Planete) Claude Castelluccia - INRIA (Planete) Hong-Yon Lach - Motorola Labs

3. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 2 Presentation overview Foreword Mobile Networks: uWhat applications need mobile routers and networks ? Definition and terminology uRequirements (What do we need to support mobile routers) Current status at the IETF: uMobile IPv6 and Mobile Networks uPrefix Scope Binding Updates in Mobile IPv6 uExtended mode in Hierarchical Mobile IPv6 Ongoing research: uInnovative trends: Multicast delivery of Binding Updates Conclusion

4. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 3 Foreword Most IP devices will be mobile ualways connected to the Internet by some means Networks will themselves be mobile umobile networks may be of any size, ranging: from a few IP devices (e.g. PAN) to thousands of IP devices (e.g. a train) There is no explicit support of mobile networks in todays IP specifications However, Mobile Networks have: uspecific characteristics, uspecific requirements uspecific problems Thus, IP needs explicit support for mobile networks

5. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 4 Mobile Networks: What applications ? Network of sensors deployed in aircrafts, boats, cars, trains, … uair-traffic signaling data exchanged with the Internet whereas passengers are given access to the Internet (web surfing, remote connection to office, …) = Mobile Router

6. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 5 Mobile Networks: What applications ? Personal Area Networks (PANs) connected to the Internet uThe mobile network is composed by all IP devices carried by humans: cellular phone, notebook, digital camera, … uDevices in the PAN may be connected using Bluetooth uThe device connecting the PAN to the Internet is a Mobile Router = Mobile Router

7. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 6 devices and networks are: ualways connected by heterogeneous networks uunified by IP Wireless WAN (IEEE 802.11b, GPRS, Bluetooth,...) Wired or Wireless LAN (WaveLAN, HiperLAN,..) john@work john@mylovelycar Picocellular MAN john@street Mobile Networks: the Mobile Network vision

8. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 7 mylovelycar@queuecar john@mylovelycar Mobile Networks: The Mobile Network vision mobile networks formed by smaller ones: A set of mobile devices which compose... a PAN which enters... a car which enters in... a queue of cars on the motorway, or in the Eurostar Shuttle = Mobile Router INTERNET queuecar@motorway

9. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 8 Mobile Networks: Internet Definition MR Mobile Node = a single node that changes its point of attachment u uby means of Mobile IPv6 Mobile Network = an entire network that changes its point of attachment u uMobile Router (MR) + its attached Nodes and Routers. u uIP subnet or a collection of IP subnets

10. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 9 Mobile Networks: Terminology uMobile Router (MR) = Border router of the mobile network unodes in the mobile networks are: SNs = all Stationary Nodes permanently located in mobile network ( SNs are not Mobile Nodes !) MNs = all Mobile Nodes temporarily visiting the mobile network uCNs = all nodes communicating with MR, SNs and MNs SN MR MN SN

11. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 10 Mobile Network: Characteristics As we have seen, mobile networks: uare always connected to the Internet through a mobile router umobile networks may be composed by a set of subnets and a set of routers usize may range for a few (PAN) to hundreds or even thousands of nodes and routers (train, etc …) upart of a mobile networks may be a sub-mobile network SN MR MN SN MR SN

12. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 11 Mobile Networks: Aim of Mobility Support to provide continuous Internet connectivity to nodes located in the mobile network to offer optimal routing between CNs and nodes located in the mobile network (both SNs and MNs) end-system SN

13. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 12 IETF Status Mobile IP Working Group: uMobile Networks are not currently supported by Mobile IPv6 uCurrent work: Prefix Scope Binding Update: draft-ernst-mobileip-v6-network-01.txt HMIPv6 draft-ietf-mobileip-hmipv6-03.txt Seamoby Working Group (Context Transfer and Micro- mobility routing): usupport of mobile routers and networks is listed by the micro- mobility design team draft-ietf-seamoby-mm-problem-01.txt IPNG Working Group (IP Next Generation or IPv6) some discussions in the mailing list MANET Working group (Ad-hoc routing) No discussion about this subject But ad-hoc network that changes its AR is a mobile network according to our definition

14. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 13 Working Group Mobile IP at the IETF. Allow mobility of end-systems without communication disruption […]: umobile node MN is identified by its home address IP1 (address on the home link) ua new temporary address IP2 (care-of address or CoA) is allocated to MN on each visited foreign link and is used for routing. uBinding between the home address and the CoA uMN is associated with a Home Agent HA (a router on the home link ) IETF Status: Mobile IPv6 for mobile nodes (review)

15. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 14 IETF Status: Mobile IPv6 for mobiles nodes (review) First packets uMN obtains CoA IP2 from a router on the foreign link uMN registers its current CoA IP2 with its home agent HA. uCN sends packets to the CoA IP1 uHA intercepts, encapsulates, and redirects packets to CoA IP2 uMN decapsulates packets Following packets uMN sends its CoA to CN. u CN sends packets directly to CoA IP2 using a IPv6 Routing Extension Header.

16. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 15 IETF Mobile IPv6 is a natural candidate to support mobile routers and networks Specification says that mobile nodes may either be Mobile Hosts or Mobile Routers. uHowever, no explicitly mention of mobile networks uCould Mobile IPv6 support mobile networks anyway ? If we follow the specification, MR: uis a mobile node and operates Mobile IPv6 uhas a home address in its home network ugets a new CoA on each visited link uregisters its new CoA address: with its HA and its own CNs by means of BUs containing current CoA => Packets intended to the MR itself are optimally routed from the CN to the MR IETF Status: Mobile IPv6 for mobile networks ?

17. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 16 IETF Status: Mobile IPv6 for mobile networks ? What about packets intended to the SNs ? CNs do not have a CoA for SNs: uNo optimal routing between CNs and SNs uPackets intended to SNs are routed to the home network uMRs HA has a binding between MRs home address and MRs CoA uPackets are intercepted by MRs HA (proxy ARP) uHA does not know that packets intended to SNs have to be encapsulated to the MRs CoA upackets enter a routing loop and get finally discarded Experiments conducted on FreeBSD has demonstrated this see draft-ernst-mobileip-network-01.txt in some implementations, it may work, but the specification does not say what to do for a mobile router => communication is not possible at all if the implementation strictly follows the specification If we want to use Mobile IPv6, it needs clarification and extensions

18. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 17 Draft-ernst-mobileip-v6.01.txt udeveloped by INRIA and MOTOROLA Labs uPresented at 48th IETF 8/00 and 49th IETF 12/00 uunder revision - new version will come before next IETF Draft addresses 2 issues: uRedirection of packets intended to SNs by the HA to the MR uOptimal Routing between CNs and SNs Proposes Mobile IPv6 extensions: uKey idea: MR is solely responsible for the mobility management of the entire network MR acts as any other MN and operates Mobile IPv6 all interfaces in the mobile network are identified by a common network prefix => the Mobile Network Prefix Binding between the Mobile Network Prefix and the MRs CoA Record in Binding Cache = network route vs host route IETF Status: Prefix Scope BU extensions to MIPv6

19. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 18 How: uThe Mobile Network Prefix is carried in BUs in addition to the CoA uA BU worth for an entire network, not for a single node uBUs are sent by the MR to the MRs HA, all CNs of the MR all CNs of SNs behind the MR uWe define a new sub-Option to record the Mobile Network Prefix A bit Prefix Scope Registration in the Binding Update option that tells BU contains a care-of address valid for a mobile network IETF Status: Prefix Scope BU extensions to MIPv6

20. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 19 Both CNs and HA are then able to redirect packets sent to any node in the mobile network uall packets with a destination address corresponding to mobile network prefix are re-routed to the MRs CoA using a routing extension header or encapsulation Security issues: uThe sender of the BU is easily authenticated uRemaining open issue: Authorization for the MR to manage mobility of the entire network But same problem as for MNs: –a MN needs to be authorized to send a BU for a home address –a MR needs to be authorized to send a BU for a network prefix –this is presently discussed at the IETF and we are waiting for the outcome of this discussion IETF Status: Prefix Scope BU extensions to MIPv6 CNs BINDING CACHE MR home address => MRs CoA = Standard Mobile IPv6 Mobile Network prefix /48 => MRs CoA = our extension

21. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 20 IETF Status: Extended mode in HMIPv6 Draft-ietf-mobileip-hmipv6-03.txt First version around 10/00 Presented at 49th IETF 12/00 Developed by INRIA (Planete) and Ericsson Research Based on original work designed at INRIA (Planete) in 1998 Hierarchical Mobility Management useparate local mobility management from global mobility management u2 modes of operation: Basic Mode and Extended Mode uExtended Mode: could be used to support mobile networks MR has 2 CoAs: –RCoA is kept as long it remains in the same administrative region –LCoA is topologically correct and changes at each new access point –MR broadcast the RCoA in the mobile network MNs (and SNs ?) in the mobile network: –use the RCoA as their CoA –register RCoA with MAP, their HA, their CNs

22. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 21 MR s Home Agent MN s Correspondent RCoA / LCoA1 RCoA MR H@ => RCoA MN H@ => RCoA LCoA1, RCoA MAP RCoA MN s Home Agent MN MR MN H@ => RCoA IETF Status: Extended mode in HMIPv6 MR has 2 CoAs: RCoA is permanent in the site LCoA changes at each new Access Router MN uses MRs RCoA as its CoA MN registers RCoA with MAP, its HA and CNs

23. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 22 RCoA / LCoA2 RCoA MR H@ => RCoA MN H@ => RCoA LCoA1, RCoA LCoA2, RCoA MAP RCoA MR s Home Agent MN s Correspondent MN s Home Agent MN H@ => RCoA MR MN IETF Status: Extended mode in HMIPv6 MN does not need to change its CoA as long as MR remains in the same administrative domain (but it still needs to send periodic Binding Updates !)

24. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 23 HMIPv6 uis more appropriate to support MNs visiting the mobile network umobility management of the MR is not transparent to the MNs Prefix Scope Binding Updates uis more appropriate to support SNs permanently located in the mobile network umobility management of the MR is transparent to the SNs Both solution may not scale to large mobile networks IETF Status:

25. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 24 Ongoing work: How to minimise signalling ? Binding Update explosion uEach SN / MN communicate with several CNs uWe want to perform optimal routing: Current CoA must be sent periodically to each CN MRs CoA if we use Prefix Scope Binding Updates MRs RCoA if we use HMIPv6 Extended Mode Periodic burst due to Binding Updates on the first link – –about 6744 bits every 10 seconds if only one CN – –about 198408 bits every 10 seconds if 100 CNs

26. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 25 Ongoing work: Multicast delivery of BUs uIf MR sends Prefix Scope Binding Updates, we note that all CNs get an identical copy of the BU uMulticast delivery of Binding Updates for large mobile networks an innovative trend

27. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 26 Ongoing work: Multicast delivery of BUs Examples on a 1000 nodes topology - CNs are selected randomly For each number of CN, MR visits the same list of ARs Graphs show the total number of links and bandwidth consumed by Binding Updates during 400 seconds for each number of CNs

28. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 27 Conclusion: Open issues Mobile routers and networks have very specific problems and requirements uThey deserve their own solutions uMany open issues to address: Mobile Router moving without its attached nodes Nested mobility: –Mobile Nodes visiting the mobile network –the car which enters in the Eurostar Shuttle is a MN (phone) in a mobile network (PAN) in a mobile network (car) in a mobile network (train) impact on routing protocols What about: uRouter advertisements sent by MR ? uMultihomed MR uNetwork Renumbering

29. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 28 Conclusion: Requirements Requirements usually associated with mobility of end-systems +: uScalability: a very large number of mobile networks mobile network comprising one or more IP subnets very large mobile networks (hundred of SNs or MNs) uOptimal use of network resources: Optimal Routing between CNs and nodes behind the MR (both SNs and MNs) Minimal signalling load Minimise bandwidth use between MR and access router uMobility transparency for nodes behind the MR uAs good security as for mobile nodes (Authentication, Authorisation,…)

30. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 29 Conclusion: In summary Mobile IPv6 can not support mobile networks as is: uredirection by the HA of packets intended to the SNs is not clear uno optimal routing between CNs and SNs Solutions: uPrefix Scope Binding Updates (MOTOROLA / INRIA) for SNs permanently in the mobile network uHMIPv6 Extended Mode (ERICSSON / INRIA) for MNs temporarily in the mobile network uMulticast delivery of Binding Updates (MOTOROLA / INRIA) for large mobile network still a research item

31. PLANETE TEAM IPCN - Thierry Ernst - May 2001 - 30 Thank you Fore more information: uhttp://www.inrialpes.fr/planete/ Draft, presentation made at the IETF and other documents IETF web site: http://www.ietf.org (MobileIP / Seamoby) uPrefix Scope Binding Update: draft-ernst-mobileip-v6-network-01.txt uHMIPv6 Extended Mode draft-ietf-mobileip-hmipv6-03.txt uSeamoby Working Group - micro-mobility design team draft-ietf-seamoby-mm-problem-01.txt