1. International Telecommunication Union ITU-T Study Group 17, Geneva, 5-14 October 2005 RMCP (Relayed Multi-Cast Protocol) Presented by Juyoung Park 13 th October 2005

2. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 2 dates IF I … oIoIf I could have watch 2002 Worldcup soccer games in my office through computer? oIoIf I can watch a most popular TV drama while I’m in office without TV set? oDoDON’T IMAGINE ONLY! USE INTERNET BROADCASTING SERVICE !!

3. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 3 dates Contents o Background o Introduction to RMCP SERIES o CONCLUSION o Reference o Q&A

4. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 4 dates We’re on o Background The Best way of Internet Broadcasting service Pros and Cons of IP multicast ALTERNATIVE WAYS of IP multicast o Introduction to RMCP SERIES o CONCLUSION o Reference o Q&A

5. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 5 dates BACKGROUND o Considerable TWO MAIN CATEGORIES of Internet broadcasting services are; Internet On-demand Broadcasting Internet VoD System Jukebox Internet Live Broadcasting Internet Live TV (IP TV) Live Radio Broadcasting Stock Tickers and so on..

6. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 6 dates BACKGROUND o What is the BEST WAY of supporting Internet Live Broadcasting service? o The answer would be IP MULTICAST !! Why? It CAN HANDLE hundreds of thousands of SIMULTANEOUS users. Because it can; SAVE network RESOURCES EFFICIENTLY REDUCE the load of a sending node’s DRAMATICALLY

7. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 7 dates BACKGROUND o But, IP MULTICAST needs; Enough MONEY TECHNICAL Solutions Complexity Functional limitations Limited data delivery service DEPLOYMENT Timing

8. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 8 dates BACKGROUND o So, WE CANNOT USE IP MULTICAST RIGHT NOW!

9. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 9 dates BACKGROUND o Then, is there other way of serving hundreds of thousands of simultaneous connection requests EFFICIENTLY on the Internet? YES, many efforts to EMULATE IP MULTICAST! As an ”ALTERNATIVE WAY OF IP MULTICAST” Replicated IP Unicast Overlay Multicast

10. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 10 dates ALTERNATIVE WAYS OF IP MULTICAST (1/2) o Replicated Unicast mechanism; How to? A server unicasts to each receivers ITERATIVELY. Weak Points Wasting network resources too much. Increasing the load of sender drastically. Good Points The EASIST WAY of implementing or deploying service.

11. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 11 dates ALTERNATIVE WAYS OF IP MULTICAST (2/2) o Overlay Multicast mechanism; How to? EACH END HOSTS or SPECIAL DEVICES emulates the IP forwarding mechanism like multicast router. Weak Points End host may face to system or power failures. So, specially designed mechanism is highly needed to keep overlay multicast robust. Good Points EASIER WAY of implementing or deploying service. Efficient Usage of Network resources.

12. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 12 dates THE AIM of RMCP o It has intention to accelerate “Internet broadcasting services” on the current Internet.

13. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 13 dates We’re on o Background o Introduction to RMCP SERIES RMCP motivation RMCP-1 : Framework RMCP-2 : one-to-many distribution Control scheme of RMCP-2 Data delivery scheme of RMCP-2 RMCP-2 testing efforts RMCP-3 : many-to-many interactive o CONCLUSION o Reference o Q&A

14. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 14 dates RMCP Motivation (1/3) o Research Motivation Multicast CAN provides an efficient delivering mechanism for 1:N or N:N communications But, it has not been deployed for the current internet So, We need a solution to prompt IP multicast deployment Also, End-host and its applications are ready to use IP Multicast

15. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 15 dates RMCP Motivation (2/3) o Several mechanisms have been proposed. Some mechanisms need special network devices Some mechanisms depend on specific applications No standardization is set

16. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 16 dates RMCP Motivation (3/3) o So, We want to make an efficient overlay multicast mechanism. Which can prompt IP multicast service right now without changing the Infrastructure of backbone network Which follows international standard

17. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 17 dates RMCP o Goal To construct and manage an optimal relayed multicast data delivery path.

18. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 18 dates RMCP o Components RMCP Data Delivery Path (when longest path is constructed) Session Manager Data Sender + SMA Data Receiver + RMA Data Receiver + RMA Unicast Internet

19. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 19 dates RMCP o What is RMCP? RMCP is one of overlay/application- layer/relayed multicast protocol. RMCP is the first one which follows international standardization process. RMCP consists of 3 separated specification.

20. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 20 dates RMCP o 3 separated specification? RMCP-1: A framework RMCP-2: Specification for SIMPLEX group applications RMCP-3: Specification for N-PLEX group applications

21. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 21 dates RMCP o Current State RMCP-1 ITU-T Recommendation & ISO IS Finished (’02~`04) RMCP-2 ITU-T draft text & ISO CD processing (`03~) Expecting ITU-T LC procedure in 2006. RMCP-3 ITU-T draft text & ISO WD processing (`04~)

22. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 22 dates RMCP-1 IN DETAIL o A framework for Relayed Multi-Cast Protocol It categorizes present Internet group services into FOUR. 1:N real-time data delivery 1:N reliable data delivery N:N real-time data delivery N:N reliable data delivery

23. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 23 dates RMCP-1 IN DETAIL o A framework for Relayed Multi-Cast Protocol It defines “two possible relayed delivery path construction” and guides two additional protocols. 1:N Overlay Multicast Data Delivery (RMCP-2) N:N Overlay Multicast Data Delivery (RMCP-3) It shows a feasible Internet broadcasting service scenario by using RMCP.

24. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 24 dates RMCP-2 One-to-many group applications? RMCP-1 IN DETAIL Session Manager MA Data Receiver + RMA MA Data Sender + SMA Data Receiver + RMA Reliable | real-time uni-directional multicast MA Data Receiver + RMA

25. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 25 dates Session Manager MA Data Sender/Receiver + SMA MA Data Sender/Receiver + SMA Reliable | real-time bi-directional multicast Many-to-many group applications? RMCP-3 RMCP-1 IN DETAIL MA Data Receiver + RMA

26. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 26 dates RMCP-1 IN DETAIL o Relationship among RMCP-series RMCP-2 RMCP-3 RMCP-1 : Framework

27. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 27 dates RMCP-2 IN BRIEF o What is RMCP-2 A real protocol which can manage one-to-many overlay multicast network (so called overlay multicast tree)

28. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 28 dates RMCP-2 IN BRIEF o Some noticeable RMCP-2 features are; 1) Initialization/ Termination Bootstrapping 2) Map discovery Inside local broadcast/multicast area Outside the area 3) Late Join / Early Leave Construct tree automatically 4) Maintenance Status monitoring Network fault recovery (loop, partition) Tree improvement 5) Data delivery scheme According to data profile

29. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 29 dates Control Scheme in RMCP-2 (1/3) o Exchanging Control Messages Media Server  SM (unicast) : implicitly Generic Session Information : Session ID, the preferred data channel type, etc (S)MA  SM (unicast) : explicitly (S)MA  MA (unicast) : explicitly media server media player Multicast Area Unicast Area session manager Multicast Area MA (Multicast Agent)

30. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 30 dates Control Scheme in RMCP-2 (2/3) o Control Messages of RMCP (Cont’d) OperationsMessagesMeaningFromTo Session Initialization SUBSREQ Subscription request MASM SUBSANS Subscription answer SMMA Tree initialization RELREQRelay requestCMAPMA RELANSRelay answerPMACMA Session leave LEAVREQLeave requestSM/PMA/CMAMA/CMA/PMA LEAVANSLeave answerMA/CMA/PMASM/PMA/CMA Session Termination TERMREQ Termination request SM/PMASMA/CMA TERMANSTermination answerSMA/CMASM/PMA

31. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 31 dates Control Scheme in RMCP-2 (3/3) OperationsMessagesMeaningFromTo Session Maintenance HBHeart beatSMA/PMAMA/CMA Session Monitoring STREQStatus report requestSMMA STANSStatus reportMASM STCOLREQ Status collect request PMACMA STCOLANSStatus collect answerCMAPMA MAP discovery PPROBREQParent probe requestMA PPROBANSParent probe answerMA HMA selection HSOLICITHead solicitMALocal Net. HANNOUNCEHead announceHMALocal Net. HLEAVEHead leaveHMALocal Net. o Message Types

32. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 32 dates RMCP-2 data delivery (1/2) o Delivering Data Media Server (Sender)  SMA (Multicast Agents) : Multicast (S)MA  MA : Unicast MA  Media Player (Receiver) : Multicast media server media player unicast tunneling Multicast Area MA : Multicast Agent Multicast Area Unicast Area

33. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 33 dates RMCP-2 data delivery (1/2) o But RMCP-2 can use any kind of data delivery scheme. For real-time data delivery IP-in-IP, CIPE, UDP tunneling for Real-time data delivery  described in Annex B For reliable data delivery TCP tunneling for Reliable data delivery  described in Annex C MA (Multicast Agent)

34. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 34 dates RMCP-2 IN DETAIL o Bootstrapping A new joiner don’t know any participated node of the session. After successful subscription, SM gives MA list to the new joiner (MA) as bootstrapping information. But, each new joiner should explore its network by itself because SM cannot know the network topology exactly. FG C

35. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 35 dates RMCP-2 IN DETAIL o Neighbor Discovery (1/2) Inside of local multicast area; Sometimes and always, a node in the same network would be the first candidate for its parent.

36. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 36 dates RMCP-2 IN DETAIL o Neighbor Discovery (2/2) Outside of local broadcast network; explore and then measure o MA does not have any information on physical network F GEDAB C CGFA E DB GF C A E DB GF C E D ABC ABC A B G F

37. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 37 dates RMCP-2 IN DETAIL o Tree construction Each MAs asks data relay to closest neighbor with hop-by-hop manner. RELREQRELANS

38. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 38 dates RMCP-2 IN DETAIL o Tree monitoring/maintenance A session manager can monitor participants arbitrarily. Each MA can detect and recover network fault by itself. STREQ STANS SM STREQ STANS

39. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 39 dates RMCP-2 IN DETAIL o Tree improvement Overlay multicast mechanism cannot guarantee whether the constructed tree is optimized. RMCP-2 probes neighbors continuously and switch its parents at need.

40. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 40 dates RMCP-2 Implementation (1/3) o Implemented system Implemented System Environment: RedHat 8.0, C, Gtk+ Implemented components : SM & MA (2002.06) Data transmission channel : IP-IP Tunneling, TCP, UDP

41. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 41 dates RMCP-2 Implementation (2/3) o Demonstration (past) Internet Real-time broadcasting on the APAN (2003.04) Internet Real-time broadcasting at the ITU- T SG17 meeting (2003.09) On going: Regular Test of Internet Real- time streaming video service among ETRI, CNU, and Kyushu Univ.

42. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 42 dates RMCP-2 Implementation (3/3)

43. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 43 dates RMCP-2 Testbed

44. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 44 dates When RMCP is applied to IPTV alike service? RMCP-2 Test

45. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 45 dates RMCP-3 IN BRIEF o RMCP-3 is under construction. It includes N:N tree construction mechanism.

46. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 46 dates We’re on o Background o Introduction to RMCP SERIES o CONCLUSION o Reference o Q&A

47. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 47 dates CONCLUSION o Now, WHAT CAN WE DO with RMCP? (1/2) EARLY STAGE RMCP as an International Standard CAN CATALYZE Internet group service! MID STAGE RMCP CAN act as an INTERIM SOLUTION for group service during the IP Multicast is being deployed.

48. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 48 dates CONCLUSION o Now, WHAT CAN WE DO with RMCP? (2/2) LAST STAGE RMCP CAN SURVIVE after the IP Multicast is Fully deployed in the next generation network. o Personal internet live broadcasting services. o As a solution for Inter-Domain multicast issues. o For mobile multicast!

49. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 49 dates We’re on o Background o Introduction to RMCP SERIES o CONCLUSION o Reference o Q&A

50. ITU-T ITU-T Study Group 17, Geneva, 5-14 October 2005 50 dates References o RMCP DOCUMENTS RMCP-1 Framework, ITU-T X.603 | ISO/IEC 16512-1 RMCP-2 for Simplex Group Applications, 2 nd CD ballot text of ITU-T X.603.1 | ISO/IEC 16512-2 RMCP-3 for N-plex Group Applications, 2 nd WD ballot text of ITU-T X.603.2 | ISO/IEC 16512-3 o RMCP Official Home-page, http://ectp.etri.re.kr/

51. International Telecommunication Union ITU-T Study Group 17, Geneva, 5-14 October 2005 Thank you! Juyoung Park Senior Researcher/Ph.D Protocol Engineering Center, ETRI jypark@etri.re.krhttp://ectp.etri.re.kr/~jypark