NSIS Signaling for QoS Models (Was: QoS Model discussion) Cornelia Kappler, Jerry Ash, Chuck Dvorak, Al Morton, Percy Tarapore, Yacine El Mghazli, Sven Van den Bosch, Attila Bader, Lars Westberg, Georgios Karagiannis draft-kappler-nsis-qosmodel-controlledload-00 draft-ash-nsis-nslp-qos-sig-proof-of-concept-01 draft-bader-rmd-qos-model-00
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NSIS Signaling for QoS Models (Was: QoS Model discussion)
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NSIS Signaling for QoS Models (Was: QoS Model discussion)
Cornelia Kappler, Jerry Ash, Chuck Dvorak, Al Morton, Percy Tarapore, Yacine El Mghazli,
Sven Van den Bosch, Attila Bader, Lars Westberg, Georgios Karagiannis
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
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
QoS Routing Function Supported Signaling & InformationExchange Parameters
BW Allocation andProtection
Y.1541 QoS Class, DS-TE class type,QoS-PAR, TRAF-PAR
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]
“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
Class 0 Class 1 Class 2 Class 3 Class 4 Class 5Un-
specified
IPTD Upper bound on themean IPTD
100ms 400 ms 100ms 400ms 1 s U
IPDV Upper bound on the1-10 -3 quantile ofIPTD minus theminimum IPTD
50ms 50 ms U U U U
IPLR Upper bound on thepacket lossprobability
1*10-3 1*10-3 1*10-3 1*10-3 1*10-3 U
IPER Upper bound 1*10-4 U
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 Classes
Example of QoS Class Acceptance withSpecified Parameter Indications
Field Name Value MandatoryField?
QoS Class Requested Class 0 YesQoS Class Response Accept YesMean Transfer Delay (IPTD) 80 ms No99.9% - min Delay Var.(IPDV)
20 ms No
Loss (IPLR) NoErrored Packets (IPER) No
Example of QoS Signaling Requirements Based on Y.1541 QoS Classes
Example of QoS Class Rejection with Alternative Offer & Indications
Field Name Value MandatoryField?
QoS Class Requested Class 0 YesQoS Class Response Reject YesQoS Class Offered Class 1 NoMean Transfer Delay (IPTD) 180 ms No99.9% - min Delay Var.(IPDV)
No
Loss (IPLR) NoErrored Packets (IPER) No
Example of QoS Signaling Requirements Based on Y.1541 QoS Classes
Example of Accumulating & Signaling Current Performance
Requested CurrentlyAchieved
QoS Class Class 0 Class 0Mean Transfer Delay (IPTD) 100 ms 20 ms99.9% - min Delay Var.(IPDV)
50 ms 10 ms
Loss (IPLR) 10-3 <10-3
Errored Packets (IPER) 10-4 <10-4
Status of ParameterIndications
Allowed
Example of QoS Signaling Requirements Based on Y.1541 QoS Classes
Example of Accumulating & Signaling Current Performance
Requested Network 1 Network 2 CurrentlyAchieved
QoS Class Class 0 Class 0 Class 0 Class 0Mean Transfer Delay (IPTD) 100 ms 20 ms 10 ms 30 ms99.9% - min Delay Var.(IPDV)
50 ms 10 ms 10 ms 15 ms
Loss (IPLR) 10-3 <10-3 <10-3 <10-3
Errored Packets (IPER) 10-4 <10-4 <10-4 <10-4
Status of ParameterIndications
Allowed Allowed Allowed
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?