Internet Architecture for Robust Mobility. Sangheon Pack (백상헌) Korea University

Transcription

1 Internet Architecture for Robust Mobility Sangheon Pack (백상헌) Korea University

2 Contents Introduction IETF Activity Home Agent Reliability Protocol P2P-based Approaches ROAM and SAMP Summary 2

3 Robust Internet? 3 25 January 2003

4 Robust Mobility? Mobility management in all-ip networks Mobile IPv4 and Mobile IPv6 HMIPv6, FMIPv6, and PMIPv6 Mobility agents: HA, FA, MAP, LMA, MAG Single point of failure How to meet five 9 s rule? How to support billions of mobile users? 4

5 IETF Activities IETF Mobility Extension for IPv6 (MEXT) WG Dual-stack operation High-availability home agents Multiple interfaces Mobile IPv6 in the presence of firewalls Specific needs of automotive and aviation communities Authentication, authorization, and accounting (AAA) 5

6 Home Agent Reliability Protocol draft-ietf-mip6-hareliability-03.txt To allow another home agent to take over and continue providing service Home agent failure detection Home agent state transfer Binding information, AAA, etc. Home agent switching 6

7 HA Virtual Switch vs. Hard HA virtual switch Switch Transparent to MNs Required IPsec/IKE sync among HAs A single HA address is shared among HAs HA hard switch MN is aware of HA switch IPsec/IKE state sync is not required. MN must establish IPsec/IKE states with multiple HAs 7 Distinct HA address is assigned to each HA.

8 Home Agent Virtual Switch 1) MN establishes IPsec SA with HA and sends BU 2) HA exchange binding and IPsec SA states with backup- HA 3) When the HA fails, backup-ha automatically takes over the failed HA ::a HA1 1) BU 2) SA and Binding States Exchange backup 2001::a HA2

9 Home Agent Hard Switch 1) MN pre-establishes IPsec SAs with all HAs 2) MN sends BU to one of HA as RFC3775 3) Binding States are exchanged among HAs 4) If HA is failed, backup-ha sends a HA switch message 9 to MNs 2001::a HA1 2)BU 3) Binding States Exchange 5)BU backup 2001::b HA2 4)HA switch

10 P2P-based Approaches S. Zhuang et al., Host Mobility Using an Internet Indirection Infrastructure, ACM Wireless Networks, 11(6), November S. Pack et al., "SAMP: Scalable Application Layer Mobility Protocol," IEEE Communications Magazine, 44(6), June 2006.

11 Peer-to-Peer Networking or overlay networking Decentralized data and resource sharing All computers have equal capabilities Distributed Hash Tables (DHT) Scalable Load balancing Fault-tolerance 11

12 Chord DHT-based P2P lookup system Uses consistent hashing to assign keys to nodes A given key (data item) is mapped onto a node. Maintains routing information as nodes join and leave the 12 K54 N58 N51 N48 N42 N38 N1 N32 Lookup (K54) N8 N14 N21

13 ROAM Overview Robust Overlay Architecture for Mobility Built on top of the Internet Indirection Infrastructure (i3) Decouples the act of sending from the act of receiving Provides a rendezvous-based communication abstraction 13

14 i3 Rendezvous-based communication m-bit identifier Insert trigger Address 14 Send Packet

15 Mobility in ROAM Preserve end-toend connectivity Change Move 15

16 ROAM Features (1/3) Routing Efficiency Trigger server caching Caches the server storing a particular trigger Sends the server directly via IP Trigger sampling To pick triggers stored at nearby servers Measures the round trip delay to the servers that store those triggers Uses the trigger with the lowest delay 16

17 ROAM Features (2/3) Fast Handoff Multicast-based handoff The MH s proxy inserts a trigger for multicast Allows the MH to take advantage of the best available connectivity Move 17

18 ROAM Features (3/3) Location Privacy 18 Chooses a trigger close to the CH Uses two triggers to preserve fast handoff

19 SAMP Overview SAMP (Scalable Application-layer layer Mobility Protocol) SIP P2P Mobility function SAMP Scalability Scalable Mobility Support 19

20 Pre-Call SIP Mobility Registrar 2 1 SIP REGISTER CH Home network MH 2 3 SIP INVITE SIP 302 temporarily 5 4 SIP INVITE 6 Visited network 5 6 SIP 200 OK Data stream 20

21 Mid-Call SIP Mobility A A Data stream CH E D C Visited network 1 B MH B C D E DHCP query New IP SIP INVITE SIP 200 OK F Visited network 2 F Data stream 21

22 SAMP Procedure (1/5) Finding a SIP server in a foreign domain REGISTER sip: sip.mcast.net SIP/2.0 From: S. Pack <shpack@domaina.com> To: S. Pack <shpack@domaina.com> Contact: CoA1 22

23 SAMP Procedure (2/5) REGISTER to Home SIP Server Home SIP Server Anchor SIP Server REGISTER sip: homedomain.com SIP/2.0 From: S. Pack <shpack@domaina.com> To: S. Pack <shpack@domaina.com> Contact: 12.domain.com

24 SAMP Procedure (3/5) Location Update: Hierarchical Home SIP Server Registration(HR) Anchor SIP Server 16 REGISTER sip: 12.domain.com SIP/2.0 From: S. Pack <shpack@domaina.com> To: S. Pack <shpack@domaina.com> Contact: CoA2 24

25 SAMP Procedure (4/5) Session establishment INVITE SIP/2.0 From: K. Park To: S. Pack Home SIP Server Anchor SIP Server 25

26 SAMP Procedure (5/5) Two-tier caching (TTC) Home SIP Server Phase I 12 INVITE sip:shpack@domaina.com SIP/2.0 From: K. Park <kwpark@domainb.com> To: S. Pack <shpack@domaina.com> Phase II 16 Anchor SIP Server 26

27 Simulation Result (1/3) Standard deviation (σ) MIPv6 HMIPv6 SAMP Hotspot parameter (α) [Load distribution] Mobile Network and Communication Laboratory 1-27

28 Simulation Results (2/3) Distance MIPv6 HMIPv6 SAMP without HR SAMP with HR [Location update] Mobile Network and Communication Laboratory 1-28

29 Simulation Result (3/3) Distance MIPv6 HMIPv6 SAMP without TTC SAMP with TTC [Session establishment] Mobile Network and Communication Laboratory 1-29

30 Summary Robustness is a key requirement for mobility in Future Internet Open Issues Trade-off between robustness and performance Multi-homing and multi-radio environments Robust Proxy Mobile IP Scalable mobility testbed Mobile Network and Communication Laboratory 1-30