Quality-of-Service Support for Mobile Users using NSIS Roland Bless, Martin Röhricht Networking 2009, Aachen

Transcription

1 Quality-of-Service Support for Mobile Users using NSIS Roland Bless, Martin Röhricht

2 Motivation 1 More and more resource demanding Internet applications and multimedia streams video broadcasts, Voice-over-IP, IPTV Inherent need for Quality-of-Service guarantees across administrative domains signaling protocol needed RSVP, NSIS lacking mobility support of earlier signaling protocols like RSVP Increasing popularity of mobile Internet devices Laptops, mobile phones (iphone), PDAs MobileIP allows for mobility in IP-based networks adjusts data path transparently Goal: Enable Quality-of-Service in mobile environments

3 Main Challenges Resource reservations new path as quickly as possible need to be setup on the by using same/adapted QoS parameters release resource reservations on old path Tight interworking needed between mobility management and signaling protocol QoS signaling should work seamlessly with handovers across access nodes 2

4 MobileIP Overview Home Network Logical Flow Correspondent Network MN HoA Tunneled Flow HA Tunnel Flow Non-Route Optimized Flow Path before movement AR 1 CN Route-optimized flows Cross-over node 3 Foreign Network A AR 2 MN Old CoA Handover MN New CoA AR 3 Foreign Network B

5 Next Steps in Signaling Overview Two-layer approach QoS NSLP NTLP, i.e. GIST path-coupled signaling signaling node discovery message transport (unreliable, reliable, secure) NSIS Signaling Layer (NSLP) NSIS Transport Layer (NTLP) Signaling Application 1 (QoS) UDP TCP TLS IPsec SCTP IPv4/IPv6 Signaling Application 2 (NAT FW) General Internet Signalling Transport (GIST) DCCP 4 Data flow QoS NSLP Signaling

6 Problems 5 NSIS protocol suite provides Basic mobility support: Session-ID remains constant even if a flow s addresses change Re-establishment of a reservation along a new path Main problems to solve get triggers from mobility events get the current addressing information provide internal interfaces required to provide the necessary information Solution focuses on MobileIPv6 management solution as mobility

7 Mobility Scenarios 6 Mobile node is sender mobility events may trigger QoS and initiator/responder NSLP actions emit new RESERVE or QUERY message QSPEC may be adapted, constant Session ID Mobile node is receiver and initiator/responder difficult to notify sender (CN), i.e. to signal in upstream direction path not known in advance difficult to determine cross-over node flow address may change profile in first-hop router must be updated at sender side available QoS at new Access Router may differ re-negotiation along whole path required

8 Solutions to Mobility Problems 7 Mobility-aware applications (e.g., SIP) could provide the necessary triggers Assumption: MobileIPv6 as mobility management protocol Provides transparent support for transport protocols/applications Flow descriptor in QoS current Care-of Address contradicts use of Mobile IP that hides mobility Mobility is not transparent to QoS also consider overhead added by MobileIP NSLP requires knowledge of for QoS NSLP, e.g., must reservations (additional headers) source address selection Main problem: notification of mobility events to QoS NSLP

9 FlowInfoService Module New approach: add FlowInfoService module allows to request information about flows, e.g., current care-of-addresses, sizes of additional headers must get updates if addresses change NSIS Protocols Application QoS NSLP GIST Flow Information Service Flow Info Request: (source addr, dest. addr) Reply/Notification: Original flow= (source addr, dest. addr) Flow status= {none, tunneled, routeopt.} New flow= (source addr, dest. addr) Overhead [bytes] 8 UDP SCTP TCP MIPv6d

10 Evaluation Setup Home Network V 5 HA AR 1 V 4 V 7 V 8 AR1 Network V 10 V 13 AR 2 V 15 V 14 AR2 Network CN Movement V 1 MN VLANs V 16 AR 3 V 17 Physical Gigabit Ethernet Link AR3 Network Virtual Environment on PC 1 9 Smart Switch (FreeBSD 7) Packet Dumps PC 2

11 Evaluation Performance Benchmarks I 50 consecutive movements of the MN between AR3 to AR2 to AR1 and back Reservation setup and tear down of old path Testcase AR1 Setup AR2 Setup AR3 Setup Tear down MN sender, sender ms 26.9 ms 37.5 ms ms initiated CN sender, sender ms 27.4 ms 40.3 ms 26.8 ms initiated MN sender, receiver ms 29.0 ms 43.1 ms 28.0 ms initiated CN sender, receiverinitiated 12.5 ms 33.4 ms 42.2 ms 31.9 ms 10

12 Evaluation Performance Benchmarks II Receiver-initiated Reservation setup delay for reservation from Access Router 1 11

13 Evaluation Performance Benchmarks III Delay for tear down of old reservation 12

14 Evaluation Performance Benchmarks IV Added additional delay between AR1/AR2 (50ms) and AR2/AR3 (25ms) Setup Delay Overhead 10% 13

15 Conclusion & Outlook 14 QoS support for mobile users viable NSIS QoS NSLP is prepared for mobility Mobility triggers required Flow Information Service Low additional overhead Code freely available: Outlook Repeating measurements in real testbed Seamless QoS support: Anticipated Handover Requires protocol extensions Ongoing implementation effort

16 Thanks! Questions? /itm