IPv6 Application Techniques in Ad-hoc Environment - A Comprehensive Guide

1. Ad hoc 환경에서의 IPv6 적용 기술 정재훈PEC, ETRIpaul@etri.re.kr

2. Contents • Introduction • Ad-hoc Routing Protocols • Autoconfiguration Technology for IPv6 MANET • Global Connectivity for IPv6 MANET • Conclusion

3. Introduction (1/2) • Categories of Wireless Networks • Infrastructured Networks • Cellular Networks, Wireless LAN (WLAN) • Infrastructureless Networks • Ad-hoc Networks • Ad-hoc Networks • 유선 기반 망 (Infrastrured Networks) 없이 무선 이동단말로만 구성된 망 • Multi-hop Routing을 위해 각 이동단말이 Router 역할을 수행함 • 용도 • 긴급구조, 전쟁, 홈 네트워크, Shopping Mall, 임시 공동작업,도로에서의 차량 간의 통신, 공항에서의 티켓팅, 사무실 등.

4. Cellular Infrastructured N/W vs. Infrastructureless N/W Internet WLAN Mobile Ad-hoc Networks

5. Introduction (2/2) • MANET에서의 이슈 • Ad-hoc Unicast Routing • Ad-hoc Multicast/Broadcast Routing • Power Saving • Automatic Support of Networking Facility in MANET • Autoconfiguration Technology • Global Connectivity for MANET

6. Ad-hoc Routing Protocols Ad-hoc Unicast Routing Protocols IPv6 Ad-hoc Routing Protocols IPv6 AODV IPv6 MAODV

7. Ad-hoc Unicast Routing Protocols Ad-hoc routing protocols Table-driven Source-initiated Demand-driven DSDV WRP AODV DSR LMR ABR CGSR TORA SSR

8. Table-driven Routing Protocols • Characteristics • Maintenance of consistent, up-to-date routing informationfrom each node to every other node in the network • Each node • maintains one or more tables to store routing information • propagates updates of network topology • Criterion of Classification of Routing Protocols • Number of necessary routing-related tables • Methods by which changes in network structure are broadcast • Examples • DSDV, CGSR, WRP, TBRPF, OLSR

9. Demand-driven Routing Protocols • Characteristics • Creation of routes only when desired by the source node • By Route Discovery Process • Route Discovery Process is completed • Once a route is found • When all possible route permutations have been examined • Maintenance of a Route • Until the destination becomes inaccessible along every pathfrom the source • Until the route is no longer desired • Criterion of Classification of Routing Protocols • Method by which route finding is performed • Examples • AODV, DSR, LMR, TORA, ABR, SSR

10. IPv6 Ad-hoc Routing Protocols • IPv6 Ad-hoc Unicast Routing Protocol • AODV (Ad-hoc On-demand Distance Vector) Routing Protocol • AODVv6 which is IPv6 AODV has been being implemented byETRI & ICU. • AODV has been already implemented by some organizations including NIST. • Linux Kernel Version: 2.4 • IPv6 Ad-hoc Multicast Routing Protocol • MAODV (Multicast AODV) Routing Protocol • MAODV works very similarly to PIM-DM. • MAODVv6 which is IPv6 MAODV has been being implemented byETRI & ICU.

11. AODV (1/3) • AODV is improved DSDV algorithm • AODV minimizes the number of required broadcasts by creating routes on a demand basis. • AODV doesn’t maintain a complete list of routes as in DSDV algorithm. • Nodes that are not on a selected path don’t maintain routing information or participate in routing table exchanges

12. AODV (2/3) • Path Discovery process • When source node doesn’t already have a valid route to that destination, it initiates a path discovery process to locate the other node. • Path Discovery • broadcasts a route request (RREQ) packet to its neighbors. • Neighbors forward the request to their neighbors, and so on until either the destination or an intermediate nodewith a “fresh enough” route to the destination is located. • Loop-free • AODV utilizes destination sequence numbers to ensure all routes are loop-free

13. AODV (3/3) a) Propagation of the RREQ b) Path of the RREP to the source

14. Autoconfiguration Technologyfor IPv6 MANET Autoconfiguration Technology? Autoconfiguration Technology for IPv6 MANET Unicast Address Autoconfiguration Multicast Address Autoconfiguration Multicast Name Resolution Service Discovery

15. Autoconfiguration Technology? • What is Autoconfiguration? • The technology that let IP-enabled devices be able to communicate one another in infrastructureless environment. • Why is Autoconfiguration needed? • To provide hosts with the automatic configuration related to networking. • To let it possible for hosts communicate when either dynamic or static configuration is impossible. • To provide the quick and easy configuration related to the network facility in MANET environment.| • Issues of IETF Zeroconf Working Group • Unicast Address Autoconfiguration • Multicast Address Allocation • Name Resolution (DNS) • Service Discovery

16. Unicast Address Autoconfiguration AutoconfigurationTechnologyin IPv6-based MANET Service Discovery Multicast Name Resolution Multicast Address Autoconfiguration Autoconfiguration Technology for IPv6 MANET • Unicast Address Autoconfiguration • Automatic configuration of a unique IP address within the scope in which the address will be used. • Multicast Address Autoconfiguration • Allocation of a unique multicast address for the application which needs a new multicast address. • Multicast Name Resolution • Translation between name andIPv6 address • Service Discovery • Discovery of the necessary serviceon the network without priorconfiguration.

17. Application Multicast NameResolution Ad-hoc Unicast Routing Ad-hoc Multicast Routing TCP / UDP B C D A E IPv6 Mobile Node Unicast AddressAutoconfiguration Multicast AddressAutoconfiguration Wireless Link NIC Autoconfiguration for IPv6 MANET • Network Configuration • Protocol Stack of Mobile Node

18. 1st Try of Host A • MAC Address - a9:bb:cc:dd:ee:ff • IPv6 Address - fec0:0:0:ffff:abbb:ccff:fedd:eeff • The address of Host A conflicts with that of Host C. Host C sends NA message to Host A. MANET Prefix EUI-64 • 2nd Try of Host A • 64-bit Random Number – 1111:2222:3333:4444 • IPv6 Address - fec0:0:0:ffff:1111:2222:3333:4444 • The address of Host A doesn’t conflict with that of any other host. This address can be used as the unicast address of Host A. Random Number Unicast Address Autoconfiguration (1/2): Extended DAD Procedure in MANET • MAC & IPv6 Address of Host C • MAC Address – a9:bb:cc:dd:ee:ff • IPv6 Address - fec0:0:0:ffff:abbb:ccff:fedd:eeff Host C Host B Host A NA message NS message Router Wireless Link Where NS : Neighbor Solicitation, NA : Neighbor Advertisement

19. Unicast Address Autoconfiguration (2/2): Procedure of Unicast Address Configuration Generation of Lower 64 bits in EUI-64 Generation of Temporary address withMANET_INIT_PREFIX and Lower 64 bits • MANET_INIT_PREFIX • fec0:0:0:fffe::/64 • MANET_PREFIX • fec0:0:0:ffff::/64 Generation of Tentative address with MANET_PREFIX and Lower 64 bits Transmission of Extended NS message Was any extended NA message received from other node? YES NO Generation of 64-bitRandom Number Configuration of Unicast address in NIC

20. Request ofMulticast Address Allocation 16-bit 64-bit 48-bit (a) Network Prefix SubnetID Interface ID Generation of Unused Group ID 8 4, 4 16 64 32 (b) ff SubnetID Interface ID Group ID Generation of a multicast address FlagsP=1, T=1 Scope5 Delivery of the multicast address RandomNumber Multicast Address Autoconfiguration • Format of Site-local Unicast Address (a) andFormat of Site-local Multicast Address (b) • Procedure of Multicast Address Allocation

21. Service of Multicast Application B C D • Multicast Service Scenario 1. Unicast Address Autoconfiguration - Booting of each Mobile Node (MN) - Unicast address configuration in NIC 2. Multicast Address Autoconfiguration - Run of Video-conferencing Tool & Creation of a new Session - Allocation of a multicast address 3. Advertisement of Sesstion information 4. Join to the new Session in MN A 5. Join to the new Session in MN E 6. Transmission of Video/Audio data by MN A 7. Transmission of Video/Audio data by MN E A E Unicast Address Autoconfiguration A B C D E 1 1 1 1 1 2 3 4 6 5 7 Multicast Address Autoconfiguration

22. Sender Responder MNR query (What is IPv6 address of “host.private.local.”?)via site-local multicast over UDP 1 MNR response (IPv6 address of “host.private.local.”)via unicast over UDP 2 Verification of MNR response- Does the value of the response conform to the addressing requirements? 3 If the result is valid, then the Sender caches and uses the response. else the Sender ignores the response and continues to wait for other responses. 4 Multicast Name Resolution Multicast Name Resolution (MNR) is performed by mDNS (Multicast DNS) • Procedure of the resolutionfrom domain name to IPv6 address in MNR

23. Service Discovery Service Discovery can be performed by MNR & DNS SRV Resource Record • Simple Zone File containing DNS SRV resource recordsfor service discovery $TTL 3600 ;; Name to Address Lookups localhost.private.local. IN AAAA ::1 ; Localhost with Loopback Address host.private.local. IN AAAA fec0:0:0:ffff::202:2dff:fe1b:e851 ; MN’s Domain Name with Site-Local Address ;; DNS SRV Resource Records _multimedia1._tcp.private.local. 4000 IN SRV 0 1 3000 host.private.local. _multimedia2._udp.private.local. 4000 IN SRV 0 1 3001 host.private.local. _service-name._protocol.domain-name TTL Class SRV Priority Weight Port Target

24. Global Connectivity for IPv6 MANET Internet Connectivity for IPv6 MANET Internet Gateway Discovery Network Mobility (NEMO)

25. Internet Connectivity for IPv6 MANET • Why do we need to support the Internet connectivity in MANET? • When mobile nodes in MANET want to communicate with hosts in the global Internet • IETF NEMO BoF has started to study the support the network mobility. • What is needed to support the global connectivity? • Internet Gateway Discovery • It informs the mobile nodes of the address of the gateway that connects MANET to the Internet.

26. Internet Gateway Discovery (1/2) • Two ways to do Internet Gateway Discovery • Extended Route Discovery • Sending RREQ (Route Request) for global prefix information &Getting RREP (Route Reply) • We need to extend RREQ / RREP of IPv6 AODV. • Extended NDP (Neighbor Discovery Protocol) • Sending MANET Route Solicitation (RS) &Getting MANET Router Advertisement (RA) • We need to extend NDP. • A node uses an arbitrary address for the discovery • Home Address • Site-local address by Unicast Address Autoconfiguration

27. Internet Gateway Discoveryby Extended Route Discovery Internet MANET GW RREP RREQ B RREQ RREQ RREP A C Routing Tabledefault: GW

28. Internet Gateway Discoveryby Extended NDP Internet MANET GW RA RS B RS RS RA A C Routing Tabledefault: GW Global Unicast Address Autoconfiguration

29. Network Mobility (NEMO) • We need to support the Network Mobility • 정의: 단말 간의 통신과 인터넷으로의 연동 지원 • 응용 분야 • PAN (Personal Area Network) • 개인 휴대기기 이동망 • Public Safety System • 재해복구 임시망 • Vehicular Network • 항공기, 버스, 자동차, 지하철 망 등. • What is MONET? • 정의: MONET(Mobile Network)는 인터넷 연동을 위해이동 라우터 (Mobile Router)를 포함한 하나 이상의 서브넷으로구성된 망. • IETF NEMO BoF에서 연구되고 있음.

30. NEMO Network Internet WLAN Cellular PAN

31. Internet Car • 약 70개의 정보단말이 내장 • 3개의 서브넷으로 구성 • Multimedia network • Car audio, Navigation system, etc. • Body network • Head light, Power window, etc. • Control network • Engine, Break, etc. • Multi-homing 제공 • 외부망과의 연동을 제공하기 위해 하나 이상의 Communication Device를 포함함. • Cellular phone, WLAN, DSRC, PHS, etc. Mobile Routers

32. Conclusion • Ad-hoc에서의 라우팅, 서비스, 인터넷 연동에 있어서 IPv6는 IPv4 보다 유리함. • 주소 자동 설정, 멀티캐스트 주소 할당, DNS 서비스, 서비스 탐색 등. • Mobile IPv6를 이용한 네트워크 이동성 제공 • IPv6로 누구나 쉽게 시간과 장소에 관계없이 통신 서비스를 제공 받을 수 있음. • Ad-hoc에서의 보안 • 유선망과 WLAN 같은 무선망보다 네트워크 보안 제공이 어렵다. • 라우팅, 서비스 등의 Security 기능이 다른 네트워크 보다 더욱 필요함.

33. References [1] Elizabeth M. Royer and Chai-Keong Toh, “A Review of Current Routing Protocols for Ad Hoc Mobile Wireless Networks”, IEEE Personal Communications, April 1999. [2] Charles E. Perkins, Elizabeth M. Belding-Royer and Samir R. Das, “Ad hoc On-Demand Distance Vector (AODV) Routing”, (work in progress) draft-ietf-manet-aodv-10.txt, January 2002. [3] Elizabeth M. Royer and Charles E. Perkins, “Multicast Ad hoc On-Demand Distance Vector (MAODV) Routing”, draft-ietf-manet-maodv-00.txt, July 2000. [4] Erik Guttman, "Autoconfiguration for IP Networking:Enabling Local Communication", IEEE Internet Computing, May/June 2001. [5] Jaehoon Jeong and Jungsoo Park, “Autoconfiguration Technologies for IPv6 Multicast Service in Mobile Ad-hoc Networks”, 10th IEEE International Conference on Networks, Aug. 2002. [6] Jung-Soo Park and Myung-Ki Shin, “Link Scoped IPv6 Multicast Addresses”, (work in progress) draft-ietf-ipv6-link-scoped-mcast-02.txt, July 2002. [7] Levon Esibov, Bernard Aboba and Dave Thaler, “Linklocal Multicast Name Resolution (LLMNR)”, draft-ietf-dnsext-mdns-11.txt, July 2002. [8] A. Gulbrandsen, P. Vixie and L. Esibov, “A DNS RR for specifying the location of services (DNS SRV)”, RFC2782, Feb. 2000. [9] Ryuji Wakikawa, et al., “Global connectivity for IPv6 Mobile Ad Hoc Networks”, draft-wakikawa-manet-globalv6-01.txt, July 2002. [10] Thierry Ernst and Hong-Yon Lach, “Network Mobility Support Terminology”, draft-ernst-monet-terminology-01.txt, July 2002.