340 likes | 478 Views
NSIS Signaling for QoS Models (Was: QoS Model discussion). draft-kappler-nsis-qosmodel-controlledload-00 draft-ash-nsis-nslp-qos-sig-proof-of-concept-01 draft-bader-rmd-qos-model-00.
E N D
NSIS Signaling for QoS Models (Was: QoS Model discussion) draft-kappler-nsis-qosmodel-controlledload-00 draft-ash-nsis-nslp-qos-sig-proof-of-concept-01 draft-bader-rmd-qos-model-00 Cornelia Kappler, Jerry Ash, Chuck Dvorak, Al Morton, Percy Tarapore, Yacine El Mghazli, Sven Van den Bosch, Attila Bader, Lars Westberg, Georgios Karagiannis
‘Goal’ • Validate QoS NSLP by combining it with three different QoS Models • A QoS Model is a mechanism for achieving QoS • E.g. IntServ, DiffServ • QoS-NSLP can signal for different QoS Model • Actual resource description is carried in the QSpec Object of RESERVE
How can we validate the operation of QoS-NSLP? • analyze and specify how QoS-NSLP signaling is used for different QoS models • clarification of what is a QoS model, and its relation to NSIS signaling • three examples: • IntServ Controlled-Load Service • Standardization work in the ITU-T for QoS signaling requirements • NSIS signaling for DiffServ aware routers(old: Resource Management in DiffServ (RMD))
First validation resultsQoS Model specific Control Information – where is it processed? • +---------------+ • | Local | • |Applications or| • |Management (e.g| • |for aggregates)| • +---------------+ • ^ • ^ • V • V • +----------+ +----------+ +---------+ • | QoS-NSLP | | Resource | | Policy | • |Processing|<<<<<<>>>>>>>|Management|<<<>>>| Control | • +----------+ +----------+ +---------+ • . ^ | * ^ • | V . * ^ • +----------+ * ^ • | NTLP | * ^ • |Processing| * V • +----------+ * V • | | * V • ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ • . . * V QoS Model specific QoS-NSLP Processing?
First validation results • State held in QNEs • processing box • Common : QoS-NSLP Processing box • QoS Model specific: QoS Model specific QoS NLSP Processing box • Resource Management box • Resource allocation dependant • Do we need a standardized feedback mechanism for failed sender-initiated reservations? • E.g. local QNE returns error RESPONSE containing why reservation failed • Next RESERVE may also fail because of a problem further down the path • Next stateful node returns error RESPONSE • E.g. RESERVE continues up to QNR, collecting more information • Terminate error RESPONSE at QNE who added the failed QSpec?
First validation results:What is a QoS Model (I) • Need to refine definition of “QoS Model” • A mechanism for achieving QoS • E.g. IntServ Controlled-Load, RMD, ITU-T • And a description of how to use QoS-NSLP to signal for it • E.g. current QoS Model IDs • After yesterdays discussion, we think that • saying “we define QoS Models for NSIS” is misleading • NSIS is about QoS Signaling Models
First validation results:What is a QoS Model (II) • A description of how to signal for a QoS Model should include: • Objects to be carried in RESERVE (i.e. QSpec), QUERY RESPONSE and NOTIFY • how that information should be treated or interpreted by the Resource Management and QoS Model specific NSLP Processing • E.g. admission control, scheduling, policy control, QoS parameter accumulation (e.g. delay)… • Role of QNEs • E.g. location, frequency, … • Usage of QoS-NSLP messages to signal the QoS model
What next? • Details of signaling for three QoS-model examples (next three presentations) • Question: Further NSIS QoS Signaling Model work • Working Group IDs? proceeding to Informational RFCs for • Examples of how NSIS can signal for QoS models • Guidelines for signaling for QoS models • Including templates for Objects carried in RESERVE (i.e. QSpec), RESPONSE, QUERY, NOTIFY? • Current QoS Model Signaling IDs differ considerably in what they describe
NSIS signaling model for DiffServ aware routers(Old: RMD QoS-NSLP model) Attila Báder, Georgios Karagiannis, Lars Westberg
Main goal • Validate how NSIS can be used for signaling within DiffServ domains
Concept QNF Interior nodes: NTLP stateless, NSLP reduced state (or stateless) QNF Edge: Stateful QNF Edge: Stateful PHR PHR QNE PHR QNE Diffserv domain PDR E2E QoS-NSLP
Basic features • Provides dynamic signaling for Diffserv routers • Scalability : • separating per-hop and per-domain reservation • per-Diffserv traffic class reservation states in interior nodes
NTLP features • Reduced NTLP functions in QNF interior nodes • Simple datagram mode transport (UDP/IP) • Routing states in QNF edge nodes and no routing states in QNF interior nodes • E2E-ignore function for some NSLP messages
NSLP features • Sender initiated reservation • Per-Diffserv traffic class reservation states in all nodes, and if needed additional per-flow reservation states in QNF edges • QSpec: PHR, PDR objects • Uses simple bandwidth as QoS parameter • PHR control fields can be modified by QNF interior nodes
Unsuccessful reservation: marking of signaling packets unsuccessful
NSIS NSLP QoS Signaling Proof of Concept(draft-ash-nsis-nslp-qos-sig-proof-of-concept-01.txt) Jerry Ash AT&T gash@att.com Al Morton AT&T acmorton@att.com Chuck Dvorak AT&T cdvorak@att.com Percy Tarapore AT&T tarapore@att.com Yacine El Mghazli Alcatel yacine.el_mghazli@alcatel.fr Sven Van den Bosch Alcatel sven.van_den_bosch@alcatel.be
Outline(draft-ash-nsis-nslp-qos-sig-proof-of-concept-01.txt) • proposed QoS signaling model based on 3 ITU-T Recommendations • later versions to specify objects & control details • Qspec template proposed • consider standardizing some signaling functions within NSLP • common to all QoS models rather than proprietary within Qspec • e.g., performance requirements such as delay, delay variation, packet loss, etc. • next steps • as in intro discussion
Background & Motivation • proposed QoS signaling model based on 3 ITU-T Recommendations on QoS signaling (summarized in the draft): • [TRQ-QoS-SIG] "Signaling Requirements for IP-QoS," January 2004 • specifies QoS parameter & control information • based on Y.1541 QoS classes • quantitative guarantees for delay, delay variation, packet loss • include CAC & restoration priority • specifies requirements for signaling IP-QoS information • at user-network interface (UNI) • across network interfaces(NNI) • enable request, negotiation & delivery of Y.1541 QoS classes from UNI to UNI, spanning NNIs as required • objects for accumulation along path • how info should be interpreted in network • [Y.1541] "Network Performance Objectives for IP-Based Services," May 2002 • specifies 6 QoS service classes • specific objectives for delay, delay variation, loss for each class
Background & Motivation • proposed QoS signaling model based on 3 ITU-T Recommendations on QoS signaling (summarized in the draft): • [E.361] "QoS Routing Support for Interworking of QoS Service Classes Across Routing Technologies," May 2003 • identifies QoS routing functions & associated parameters to be signaled across networks
Qspec Template(draft-ash-nsis-nslp-qos-sig-proof-of-concept-01.txt) • QSpec ID (allows IANA reservation of QSpec parameter combinations): • IANA specified • Traffic Envelope/Conformance: • algorithm is token-bucket • conformance parameters • token bucket rate (Br) • peak rate (Rp) • peak bucket size (Bp) • sustainable rate (Rs) • sustainable bucket size (Bs) • maximum allowed packet size (M) • Excess Treatment: • excess traffic may be dropped, shaped and/or remarked. • excess treatment (EXTR)
Qspec Template(draft-ash-nsis-nslp-qos-sig-proof-of-concept-01.txt) • Offered Guarantees: • QoS-REQUEST-PAR are qualitative guarantees • Y.1541 QoS class • DiffServ behavior • service identity (SI) • class type (CT) • link capability (LC) • QoS-ACCUM-PAR are quantitative guarantees • transfer delay, delay variation, packet loss • used in RESERVE/QUERY or RESPONSE message to collect information along the path • Service Schedule: • indicates start time & end time of service • specified in Appendix B/[TRQ-QoS-SIG]
Qspec Template(draft-ash-nsis-nslp-qos-sig-proof-of-concept-01.txt) • Priority and Reliability: • CAC Priority (CAC-PRTY) • Restoration Priority (RES-PRTY) • Monitoring requirements: • As specified in Appendix B/[TRQ-QoS-SIG]
Next Steps • progress draft as an individual Informational RFC • with feedback & review by NSIS WG • seek IANA registration for QoS model • consider standardizing some signaling functions within NSLP • common to all QoS models rather than proprietary within Qspec • e.g., performance requirements such as delay, delay variation, packet loss, etc.
Background & Motivation(draft-ash-nsis-nslp-qos-sig-proof-of-concept-01.txt) • “NSLP for Quality-of-Service Signaling” provides • an NSIS signaling layer protocol (NSLP) to signal QoS reservations • support for different reservation models • a generic Qspec template to specify individual QoS signaling models • “there are already a number of QoS models specified outside of the IETF, for example the ITU, 3GPP, etc… [we should] allow consenting peers to use the QoS NSLP with particular QoS models… one way to achieve this is to use IANA registries to register QoS models, and the QoS NSLP to signal these.” • John Loughney, 27 October 2003 • “take 1 or 2 existing QoS models & detail them in a separate draft, as a sort of proof-of-concept for the QoS NSLP” • John Loughney, 19 November 2003
Y.1541 Network Performance Objectivesfor IP-Based Services • Y.1221-based Traffic Contracts • IP transfer capabilities include: the service model, traffic descriptor, conformance definition and any QOS commitments. • Transfer Capabilities include Dedicated Bandwidth, Statistical Bandwidth, and Best Effort.
Example of QoS Signaling Requirements Based on Y.1541 QoS ClassesExample of QoS Class Acceptance withSpecified Parameter Indications
Example of QoS Signaling Requirements Based on Y.1541 QoS ClassesExample of QoS Class Rejection with Alternative Offer & Indications
Example of QoS Signaling Requirements Based on Y.1541 QoS ClassesExample of Accumulating & Signaling Current Performance
Example of QoS Signaling Requirements Based on Y.1541 QoS ClassesExample of Accumulating & Signaling Current Performance
A QoS Signaling Model for IntServ Controlled-Load Draft-kappler-nsis-qosmodel-controlledload-00 Cornelia Kappler, Siemens AG
What is IntServ Controlled-Load Service? • IntServ Controlled Load Service is (in NSIS terms) a QoS Model • This ID is the corresponding NSIS QoS Signaling Model • How to signal for IntServ Controlled Load using NSIS • RFC 2210 specifies how to signal for Controlled-Load Service using RSVP • Controlled-Load Service (RFC 2211) • Provides approximately e2e service of an unloaded best-effort network • QoS parameters signaled are Token Bucket and MTU • Implemented per “network element”, i.e. per-router or per-subnet • Can be used for • Reserving resources per-flow per-router • Admission control at edge of DiffServ domains • Admission control into MPLS clouds
How to signal for Controlled-Load Service with NSIS • Role of QNEs • One or more QNE per “network element” • QoS-model specific Control Information • None • Content of QSpec • Token bucket and MTU • Objects to be carried in RESPONSE and QUERY • Tbd. Query for MTU? • Processing Rules in QNEs • Admission Control based on token bucket and MTU conformance • How find out about MTU? • Cf discussion of “feedback on failed reservations” • Usage of QoS-NSLP messages • Sender-initiated RESERVE • QUERY for finding out about MTU of path before reserving?
Backup:First validation results • Format of QSpec? • Separate immutable from mutable fields? • In RSVP: mutable fields are in AdSpec • Separate QoS Model Specific Control Information from QoS parameters?