QoS Issues in Heterogeneous IP Networks Lecture 4 of 4: QoS in heterogeneous IP Networks Wendong WANG Broadband Network Research Center (BNRC) State Key Laboratory of Networking and Switching Technology School of Computer Science & Technology Beijing University of Posts and Telecommunications September 2006
Contents Overview Course introduction QoS background QoS Concept QoS Standardization QoS Technologies QoS in heterogeneous IP Networks 2
QoS in heterogeneous IP Networks 3
Agenda QoS in heterogeneous fixed IP Networks QoS management QoS measurement QoS in wireless IP Networks QoS in heterogeneous fixed/wireless IP Networks 4
QoS in heterogeneous fixed IP Networks 5
IntServ over DiffServ LAN/WAN edge routers Network Links Enabled RSVP messages Disabled RSVP messages Reserved Data Packets DiffServ Data Packets R R R L/W 1 L/W 2 R Host IntServ/RSVP R R R IntServ/RSVP Host DiffServ Network 6
DiffServ over MPLS/MPLS TE As 100 As 200 IGP OSPF EBGP As 500 EBGP IGP OSPF DiffServ IBGP EBGP DiffServ IGP OSPF EBGP As 300 MPLS/MPLS TE IGP OSPF As 400 7
IntServ vs DiffServ vs MPLS/MPLS TE 8
QoS Management 9
Time Scales of different QoS mechanisms 10
QoS Management Model User/Service Requirement Specification Long Term Control Traffic dimensioning CAC Short Term Control Resource allocation Feedback Control Congestion Detection Performance Analysis Performance statistic Performance Monitoring 11
QoS Management Service Specification:Source/Destination IP Address, Source/Destination port number, etc. Service scope: Networks, Ingress ER, Egress ER, etc. Service type: VoIP, VoD, VPN, etc. Service performance: Bandwidth, Delay, Jitter, Loss, etc Service duration: Start/Stop time. Service traffic processing strategies Other issues for service contact (Discount, special packets, etc. ) 12
Layered Services Specification Service Level Agreement (SLA) Service Level Specification (SLS) QoS Class Per Domain Behavior(PDB PDB) Per Hop behavior(phb PHB) Traffic Conditioning block Service contract Technical & non-technical issues IP Service traffic characteristics Network QoS guarantee Network QoS capabilities Edge to Edge traffic aggregates QoS Capabilities: TCA/TCS Core and Edge routers QoS Mechanisms (WFQ, RED) Implementation Products specifications 13
SLA and Dynamic SLA SLA: Static SLA, Service provisioning with QoS guarantee but without feedback control. Pros. : Easy to deployment Dynamic SLA: Service provisioning with QoS guarantee and feedback control Pros.: High resource utilization Current Situation: Normal SLA SLA Management Part of Dynamic SLA 14
Qbone Bandwidth Broker Interface: User/Application Interface: resource allocation request Intra-Domain Interface: Router QoS configurations Inter-Domain Interface: Admission control and SLA negotiations between BBs Entities: Routing info Data store Policy entity Network management entity 15
Intra-Domain BB 16
Inter-Domain BB 17
计算机科学与技术学院计算机科学与技术学院国家重点实验室国家重点实验室宽带网研究中心宽带网研究中心 18 18 User Agent QoS Mgt. Service subscription QoS Measurement Performance QoS Charging Charging info QoS Mgt.Sys. ER ER ER CR CR CR CR AS1 ER ER ER CR CR CR CR AS3 ER ER ER CR1 CR CR CR AS2 ER ER ER CR1 CR CR CR AS4 User User User Probe Probe Probe Probe Implementation Example Implementation Example
Logically layered Internet 19
Expected Results Voice (EF) Video (AF) EF AF Web, Ftp (BE) BE 20
NP Server 1 Service Level Agreement Mapping QoS Admission Control. SLA/SLS NP Server 2 SLA/SLS Build a SLA! Build a SLA! (Draft) Build a SLA! Mapping QoS Admission Control. Sign successfully! Post parameters (Final SLA) Service Level Agreement (Draft) Browse Service Choose Service On SP WebSite Sign Successfully! (Final SLA) 21
QoS Measurement 22
Object of Internet Measurement Network performance monitoring Network operation and maintenance Network dimensioning and optimization Network QoS validation Network performance research QoS Control QoS Management QoS Charging Internet Measurement 23
IP Measurement Standards ITU-T Y.1540/I.380: IP packet transfer and availability performance parameters IP Packet Transfer Delay (IPTD) E2E IP Packet Delay Variation (IPDV) IP Packet Error Ratio (IPER) IP Packet Loss Ratio (IPLR) percent IP service unavailability (PIU) percent IP service availability (PIA) IETF RFC2330: Framework for IP Performance Metrics IP Measurement Framework Measurement Metrics Measurement Mothodology IETF RFC 2544: Benchmarking Methodology for Network Interconnect Devices Discusses and defines a number of tests that may be used to describe the performance characteristics of a network interconnecting device Describes specific formats for reporting the results of the tests 24
IP Measurement Parameters Parameters Connectivity Routing and topology estimation Packet latency (One way/round trip delay) Packet jitter Bandwidth Bandwidth capacity: max throughput a link can sustain, Available bandwidth: usable bandwidth Bulk transfer capacity: rate that a new single long-lived TCP connection would obtain over a path Packet loss rate 25
IP measurement categories Active measurement Passive monitoring End to end measurement Router based measurement 26
Active & Passive Active measurement Measurer generates own traffic and exams the results E.g. ping, traceroute, Passive monitoring Measurer looks at headers of user s traffic E.g. netflow, Interception Measurer can even see content of user s traffic E.g. sniffer 27
Distributed E2E performance measurement Administrator (6) (1) (7) PC Web Server Database Server Measurement Server (2) (3) (5) Measurement Node 1 Measurement Node 2 28 (4) Measurement Node 3
QoS measurement architecture Monitor GUI Corba User Int. Workstation SLS Mon Data Net Mon Node Mon 29
Measurement Data Node Measurement Delay, Loss of each PHB Bandwidth of each PHB Bandwidth utilization of each PHB Network Measurement E2E delay, loss ratio, jitter, throughput SLS Measurement Service E2E delay, loss ratio, jitter, throughput User SLS parameters in Ingress node User SLS parameters in Egress node 30
QoS in wireless IP Networks 31
WiMAX Network Reference Architecture SS MS http://www3.ietf.org/proceedings/05nov/slides/16ng-4.pdf 32
WiMAX Service Categories http://www.wimaxforum.org/news/downloads/mobile_wimax_part1_overview_and_performance.pdf 33
WiMAX QoS Framework http://www3.ietf.org/proceedings/05nov/slides/16ng-4.pdf 34
WiMAX QoS Architecture Quality of Service Support in IEEE 802.16 Networks; IEEE Network March/April 2006 35
QoS in WLAN HUA ZHU, MING LI, IMRICH CHLAMTAC, AND B. PRABHAKARAN; A SURVEY OF QUALITY OF SERVICE IN IEEE 802.11 NETWORKS, IEEE Wireless communications Magazine, Aug.,2004 Research in providing QoS guarantee in IEEE 802.11 WLANs can be classified into the following three categories: Service differentiation mechanism Link adaptation in the physical layer Admission control strategies in MAC and higher layers 36
QoS in WLAN (1) Service differentiation A SURVEY OF QUALITY OF SERVICE IN IEEE 802.11 NETWORKS, IEEE Wireless communications Magazine, Aug.,2004 37
Link adaptation QoS in WLAN (2) A SURVEY OF QUALITY OF SERVICE IN IEEE 802.11 NETWORKS, IEEE Wireless communications Magazine, Aug.,2004 38
QoS in WLAN (3) Admission control strategies A SURVEY OF QUALITY OF SERVICE IN IEEE 802.11 NETWORKS, IEEE Wireless communications Magazine, Aug.,2004 39
QoS in heterogeneous fixed/wireless IP Networks 40
UMTS Architecture Radio Access Network 41 Core Network
UMTS Architecture R R Alternative Access Network Um Uu CAP TE MT ERAN Iu-ps' TE MT UTRAN Iu Applications & Services SCP Gr Gp HSS SGSN Mh Gn Gc Cx Gf Gi EIR Legacy mobile signaling Network R-SGW Ms CSCF Mr MRF Gi GGSN Mw Gi Mg CSCF Mm MGCF MGW Gi Mc Multimedia IP Networks T-SGW PSTN/ Legacy/External Gn SGSN GGSN Other PLMN Signalling Interface Signalling and Data Transfer Interface 42
UMTS QoS Architecture 43
UMTS QoS Management QoS management functions for user plane: Keeping user traffic accord to the traffic profile Managing the network resources for QoS guarantee QoS management functions for the control plane: Traffic admission control for QoS guarantee Policy enforcement or authorization 44
QoS in UMTS User Plane 45
QoS in UMTS Control Plane 46
UMTS Service Classes 47
UMTS QoS Classes 48
UMTS QoS Classes Parameters Class Traffic Type Delay Buffering Bit rate Example Conversation Symmetric Minimum fixed No Guarantee Video telephony Streaming Asymmetric Minimum variable Allowed Guarantee Multimedia services Interactive Asymmetric Moderate variable Allowed Not guarantee Internet (Web browsing) Background Asymmetric Big variable Allowed Not guarantee Email 49
UMTS Bearer Service Attributes 50
IMS Architecture 51
IMS Entities CSCF: call session control function Session control based on SIP signaling; 3 types: serving S-CSCF, interrogating I-CSCF, and proxy P-CSCF HSS: home subscriber server central subscriber database SLF: subscriber location function mapping to subscriber address to HSS MRF: media resource function media contents BGCF: breakout gateway control function SIP server with routing functionality AS: application server Can host and execute services, three types: SIP AS SIP applications server; OSA AS open services access service capability server; IM SSF IP multimedia service switching function MGW: media gateway bearer data transfer MGCF: media gateway control function CCF: charging collection function CSCFs, BGCFs, MRFCs, ASs send accounting information to a CCF which generates CDRs (3GPP TS 32.225) SGW: Signaling Gateway IP to PSTN 52
3GPP IMS Architecture Application Layer Parlay App Server OSA SCS Web Portal SIP App Server Diameter Centralized Databases HSS Support Systems Billing Mediation, Fault Correlation, Operations, Maintenance, SIP Session Control Layer MRFC SIP S-CSCF SIP I-CSCF P-CSCF PDF BGCF MGCF SIP Media and End Point Layer H.248 Media Server SIP COPS SIP IP Signalling Converter H.248 Media Gateway PSTN IN Access SG SS7 Wireline and Wireless SIP Endpoints GSM, UMTS, 802.11, Bluetooth, DSL, FTTP, Legacy IP Endpoints & PBXs H.323 and MGCP TDM PBX Analog Endpoint 53
IMS Layer Architecture Applications Layer End-user telephony service logic AIN call trigger points Non-telephony based services APIs for enterprise & legacy applications Session Control Layer End Point Registration Session setup QoS establishment Transport & Endpoint Layer Bearer Services, Media Conversion(PCM>IP) Special functions: announcements, touch tones collection, voice recognition, speech synthesis 54 OSA-GW Telephony AS Non-telephony AS CSCF, BGCF MGCF & MRFC HSS Media Gateway Media Server
Basic IMS Call procedure 1 2 Initiate SIP Invitation Retrieve Subscriber Profile (if needed) 3 Apply Service Logic 4 5 Retrieve Address of CLD Party Home Network and Forward INVITE. Identify Registrar of CLD Party and Forward INVITE. 6 Retrieve Subscriber Profile (if needed) 7 Apply Service Logic 8 Forward INVITE to CLD Party 9 SDP Negotiation / Resource Reservation Control 10 Ringing / Alerting 11 Answer / Connect Control Bearer Calling Party Home Network AS HSS 2 Diameter 3 SIP S-CSCF 4 DNS I-CSCF Diameter 5 HSS 6 Diameter 7 S-CSCF SIP Called Party Home Network AS SIP 8 SIP Calling Party Visited Network P-CSCF P-CSCF Called Party Visited Network 11 10 UE 1 RAN Backbone Packet Network RTP Stream Backbone Packet Network RAN 9 UE 55
End to End QoS Call Flows 56
Summary QoS management and measurement QoS in heterogeneous fixed IP Networks QoS in wireless IP Networks QoS in heterogeneous fixed/wireless IP Networks 57
References Http://qos.internet2.edu/wg/documents-informational/20020709-chimento-etal-qbonesignaling/ IETF RFC 2544: Benchmarking Methodology for Network Interconnect Devices IETF RFC2330: Framework for IP Performance Metrics HUA ZHU, MING LI, IMRICH CHLAMTAC, AND B. PRABHAKARAN; A SURVEY OF QUALITY OF SERVICE IN IEEE 802.11 NETWORKS, IEEE Wireless communications Magazine, Aug.,2004 Http://www.wimaxforum.org/news/downloads/Mobile_WiMAX_Part1_Overview_and_Perf ormance.pdf Claudio Cicconetti, Luciano Lenzini, Enzo Mingozzi and Carl Eklund. Quality of Service Support in IEEE 802.16 Networks, IEEE Network, vol. 20, no. 2, March 2006, 3GPP TS 23.101: General UMTS Architecture 3GPP TS 23.107: Quality of Service (QoS) concept and architecture 3GPP TS 23.207: End-to-end Quality of Service (QoS) concept and architecture 3GPP TS 23.228: IP Multimedia Subsystem (IMS) - stage2 3GPP TS 24.228: Signalling flows for the IP multimedia call control based on SIP and SDP 3GPP TS 29.208: End to end Quality of Service (QoS) signalling flows 58