Mobility Support by the Common API for Transparent Hybrid Multicast

Transcription

1 Mbility Supprt by the Cmmn API fr Transparent Hybrid Multicast draft-irtf-samrg-cmmn-api-03 Prject Matthias Wählisch, Thmas C. Schmidt, Stig Venaas {waehlisch, 1

2 Prblem: Grup Cmmunicatin There are many frms f grup cmmunicatin: ASM, SSM, (restricted) Bradcast, Multi-destinatin Ruting (XCast), Cntent-centric Pull Tw basic services: - Scalable packet distributin t a receiver grup - Publish/Subscribe ptin with rendezvus prcess Universal, easy access requires an abstract ntin 2

3 Prblem: Multicast Technlgies Member A There are many multicast technlgies IPv6 IPv4 - n different layers Member B n the same layer Prgrammers decide n its use - nt even DNS helps Mbility bund t technlgy IPv6 Member A mygrup.rg IPv4! Prblem: Identify same grup in different technlgies Member B mygrup.rg 3

4 Objectives Prvide a slutin fr grup apps t be cmpiled nce and run everywhere - Make use f multicast technlgies if available - Allw fr hybrid / pluralistic netwrk cnditins - Prvide a universal service access - Decuple applicatin success frm infrastructure deplyment - Supprt vertical mbility acrss service instantiatins 4

5 Naming and Addressing "Multicast addresses are a set f distributed applicatin names" Jhn Day (Patterns in Netwrk Architecture) 5 Just use any applicatin name? Prblem f mapping t netwrk addresses: ut f cntrl withut namespace supprt Dmains may run same technlgy but remain islated Dmains may run distinct technlgies but hst members f the same grup High-level meta data type easy fr prgrammers Prpsal: Use abstract, namespace-aware data type - URIs fr late binding + new API Member G Member CNN Member <sip:*@peanuts.rg> IPv6 IPv4 Member <sip:*@peanuts.rg> Member CNN IPv6 Member G

6 Prpsed URI Scheme scheme "://" grup instantiatin ":" prt "/" sec-credentials - scheme: specificatin f assigned ID - grup: identifies the grup - instantiatin: ID f the entity that generates the instance f the grup (SSM surce, RP, verlay nde) - prt: ID f a specific applicatin at a grup instance - sec-credentials: ptinal authenticatin Examples: - ip:// @ :5000/grupkey - paque://mygrup.rg 6

7 Cmmn Multicast API Draft Idea: Mve cmplexity frm applicatin t the system level The current draft prvides a cmmn multicast API n app. layer that abstracts grup cmmunicatin frm distributin technlgies abstract naming and addressing by multicast URIs cannical mapping between naming and addressing definitin f prtcl interactin t bridge multicast data between verlay and underlay 7

8 Example: SIP cnferencing (SSM) INVITE SIP/2.0 Cntact: Applicatin: ms=createmscket() ms.jin(uri( )) Aside: allws extensin fr aggregatin: 8

9 Cmmn Multicast API & Middleware Src my grup.rg Applicatin Level OS Level MulticastScket msck = new MulticastScket(); msck.send(data, mygrup.rg ); 1. Mapping f Grup Name t Addresses 2. Send data t technlgy specific interfaces hash(mygrup.rg) Mapping f names t technlgies at run-time Late binding by ID Lcatr Split 9

10 Implementatin: The HAMcast stack Applicatin library: Maps API calls & signaling t OS layer Easily integrates new prgramming languages (C++, Java) OS Middleware: - Separates generic multicast lgic frm technlgyspecific instantiatins - User-space prcess, runs nce per hst (C++ ) Service Mdules - Specific t multicast technlgies, currently IPv4, IPv6, and Scribe-ALM 10

11 HAMcast Stack Overview 11

12 Mbility Applicatin transparent due t ID-lcatr split Mbility management - within service mdule (hrizntal handver) - at generic middleware (vertical + hrizntal handvers) Middleware mbility - Hlds abstract grup lgic (pub/sub states) - Can dynamically add/remve technlgy mdules - Mbility is merely a task f the service selectin - Generic apprach: Find & imprve grup cnnectivity 12

13 Thank yu Mre abut this in the meeting f SAMRG Tday 17:40 19:40 Prject Website: Prttype fr Dwnlad: Nw versin 0.3 (mbility yet t cme) Check fr updates 13