Publisher Mobility Support in Content Centric Networks

Transcription

1 ICOIN Publisher Mobility Support in Content Centric Networks Dookyoon Han, Munyoung Lee, Kideok Cho, Ted Taekyoung Kwon, and Yanghee Choi Seoul National University Multimedia and Mobile communications Laboratory

2 Introduction (1/2) Current Internet architecture Host-based communication model Designed to share resources Considering where to receive Internet traffic is already content-oriented Users/applications care what to receive So, host-based communication model is outdated 2/18

3 Introduction (2/2) Novel Internet architectures were proposed to solve the cognitive mismatch Information Centric networking (ICN) New paradigm Redesign the Internet in a clean-slate manner DONA(Data-Oriented Network Architecture) PSIRP(Publish-subscribe Internet Routing Paradigm) NetInf(Network of Information) CCN(Content Centric Networking) 3/18

4 CCN Overview A subscriber sends Interest packet to request content and receives Data packet for the content Components for communication Forwarding Information Base (FIB) Forwarding table Allows a list of outgoing interfaces Pending Interest Table (PIT) Keeps track of Interest forwarded Content Store (buffer memory) Caches Data packets /parc.com/videos/summer.mpg/v1/s0 4/18

5 Illustration of CCN work Effect of in-network caching (content store) A snu.ac.kr / video1.avi B H D G I E Interest Data Client 1 Client 2 5/18

6 Mobility Support in CCN Mobile broadcasting Interaction application Mobile chatting Supporting subscriber mobility is relatively easy Due to CCN s receiver driven nature, consumers can retransmit interest after establishing new connectivity How about publisher mobility? Need FIB update 6/18

7 Main Challenges Maintain a valid path to the mobile publisher Path towards mobile publisher always needs to be valid Outdated FIB entry cannot be used Fast FIB establishment To forward interest packets correctly, FIB should be updated as soon as possible Cannot rely on the routing protocols (e.g., OSPF, RIP) due to longer convergence time while preserving CCN architecture 7/18

8 Related Work Mobility support in content centric network (Do-hyung Kim, et al. KAIST, ICN2012) A content provider mobility solution of named data networking (Xiaoke Jiang, et al. Tsinggua university, ICNP 2012) DNS-like control server matches name & location which may cause Scalability issue Single point of failure Bottleneck problem Indirection delay Name / Location coupling violate the ICN philosophy When you move, you change your address 8/18

9 PMC Overview Goal: support a Publish Mobility in CCN (PMC) Design principles No central entity dealing with mobility Do not use location information Do not violate the philosophy of CCN architecture Our approach Maintain two types of entries in FIB Handle mobility event (using Interest / Data packet ) 9/18

10 PMC: FIB maintenance Original entry and Mobility entry in FIB Original entry Ordinary entry for stable and long-lived destination Maintained by routing protocol Mobility entry Special entry for mobile and temporal destination Maintained by PMC Relatively high priority (with short-timer value) Name prefix Original entry Mobility entry snu.ac.kr interface-a interface-b 10/18

11 PMC: mobility handling (1/2) PMC router Handles publisher s mobility event FIB update Home router of publisher PMC router that announces original entry for publisher s prefix Mobile publisher Produce the (real-time) content Send a special Interest packet to maintain the mobility entry Publisher URL/mobilityReport/Home Publisher URL/mobilityReport/PrevPoA * PoA: point of attachment 11/18

12 PMC: mobility handling (2/2) 12/18

13 PMC operation (Home New PoA) Mobile publisher reports mobility event to the previous PoA (home router) with Interest packet (3) (2) Data Mobility & FIB report update (1) Mobility event (4) Content download snu.ac.kr/alicenews/mobilityreport/prev PoA Data packets are sent back & inter-nodes updates FIB (mobility entries) Home router forwards stored Interests to the publisher (/AliceNews.kr) Following Interest packets are forwarded along the new path 13/18

14 PMC operation (PoA New PoA) (2) (3) Mobility Data & report FIB update (4) Content download snu.ac.kr/alicenews/mobilityreport/home Mobile publisher reports his mobility to Home router & previous PoA snu.ac.kr/alicenews/mobilityreport/prev PoA (/AliceNews.kr) (1) Mobility event Data packets are sent back & inter-nodes updates FIB (mobility entries) Home router and PoA forwards stored Interests to publisher Following Interest packets are forwarded along the new path 14/18

15 Simulation Environment Topology Home router exists in ISP hand-off occurs in single ISP Comparison schemes PMC Indirection Pure-CCN Uses a DNS-like mobility management server Event-driven simulator Parameters CS size: 10 GB FIB size: 10,000 entries PIT timer: 3,000 ms Interest packet size: 125 byte Chunk(content) size: 2500 kbyte Request term: 3,000 ms Reference for parameters setting: - An effective hop-by-hop Interest shaping mechanism for CCN communications, NOMEN CCNx project ( ) 15/18

16 Evaluation Result (1/2) Chunk delivery delay delivery delay = retrieval time of the data packet - issuing time of the initial interest packet PMC shows shorter handover delay than Pure-CCN Indirection is stable. But, overall delay is longer than PMC Handover delay 16/18

17 Evaluation Result (2/2) Chunk retrieval rate Sequence number of received data packet - Publisher mobility decreases the retrieval rate of Pure-CCN - Indirection shows low retrieval rate due to the indirection delay (bypassing) - PMC shows stable retrieval rate since it handles mobility event quickly PMC can meet delay-critical QoE service i.e., voice in a wireless context has one way delay requirement of 200~250ms 17/18

18 Conclusion & Future work Supporting publisher mobility is one of key challenge to adapt CCN into real world application these days PMC suggests fast FIB update method to support publisher s mobility in CCN Future work Fast flooding scheme to support mobility event Managing mobility between different ISPs 18/18

19 Thank you 19/18