One document matched: draft-bader-nsis-rmd-diffserv-qsm-00.txt


NSIS Working Group                                        Attila Bader
INTERNET-DRAFT                                           Lars Westberg
                                                              Ericsson
Expires: January 2005                             Georgios Karagiannis
                                                  University of Twente
                                                      Cornelia Kappler
                                                               Siemens
                                                            Tom Phelan
                                                                 Sonus
                                                         July 10, 2004



   Resource Management In Diffserv: An NSIS QoS Signaling Model for 
                          Diffserv Networks
              <draft-bader-nsis-rmd-diffserv-qsm-00.txt>



Status of this memo


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   disclosed, in accordance with RFC 3668.   


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Abstract


   Resource Management in Diffserv (RMD) is a technique for adding 
   admission control to Differentiated Services (Diffserv) networks.  
   RMD complements the Diffserv architecture by pushing complex 
   classification, conditioning and admission control functions to 
   the edges of a Diffserv domain and simplifying the operation of 
   internal nodes.  It allows feedback to systems outside of the 
   Diffserv domain on the availability of resources for individual 
   flows within the domain while aggregating end-to-end resource 
   reservations at the edge of the domain to reduce the burden on 
   internal nodes.



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   This document describes the RMD concept and an NSIS QoS Signaling 
   Model for Diffserv.  The RMD QoS Signaling Model allows devices to
   use the NSIS QoS-NSLP protocol to signal reservation requests from
   devices outside the Diffserv domain to edge nodes in the domain, 
   edge nodes to aggregate the requests and signal the aggregated 
   requests through internal nodes along the data path to the egress 
   edge nodes, and for egress edge nodes to signal the original, 
   disaggregated, requests to outside devices.




Table of Contents


   1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
   2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . .4
   3. Overview of RMD QoS Model and QoS Signaling Model . . . . . .4
      3.1 RMD QoS Model . . . . . . . . . . . . . . . . . . . . . .4
      3.2 RMD QoS Signaling Model Overview . . . . . . . . . . . . 5
   4. RMD QoS Signaling Model detailed description . . . . . . . . 6
      4.1 Role of QoS NSLP Entities (QNEs) . . . . . . . . . . . . 6
      4.2 QSpec Definition . . . . . . . . . . . . . . . . . . . . 6
          4.2.1 RMD QoS descriptors . . . . . . . . . . . . . . . .7
          4.2.2 RMD control information . . . . . . . . . . . . . .7
          4.2.3 Mapping of QSpec parameters onto generic 
                QSpec Parameters . . . . . . . . . . . . . . . . . 8
      4.3 Message format . . . . . . . . . . . . . . . . . . . . . 8
      4.4 State management . . . . . . . . . . . . . . . . . . . . 8
      4.5 Operation and sequence of events . . . . . . . . . . . . 8
          4.5.1 Edge discovery and addressing of messages . . . . .9
          4.5.2 Basic unidirectional operation . . . . . . . . . . 9
             4.5.2.1 Successful reservation. . . . . . . . . . . . 9
             4.5.2.2 Unsuccessful reservation . . . . . . . . . . .9
             4.5.2.3 Severe congestion. . . . . . . . . . . . . . .9
          4.5.3 Basic bidirectional operation . . . . . . . . . . 10
   5. Security Consideration. . . . . . . . . . . . . . . . . . . 10
   6. IANA Considerations. . . . . . . . . . . . . . . . . . . . .10
   7. Open issues. . . . . . . . . . . . . . . . . . . . . . . . .10
   8. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . .11
   9. Authors' Addresses. . . . . . . . . . . . . . . . . . . . . 11
   10. References . . . . . . . . . . . . . . . . . . . . . . . . 12
   11. Appendix: QoS models, QoS Signaling Models and Qspecs . . .12













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1. Introduction


   The Differentiated Services (Diffserv) architecture ([RFC2475], 
   [RFC2638]) was introduced as a result of efforts to avoid the 
   scalability and complexity problems of Intserv [RFC1633]. 
   Scalability is achieved by offering services on an aggregate basis 
   rather than per-flow and by forcing as much of the per-flow state 
   as possible to the edges of the network. The service 
   differentiation is achieved using the Differentiated Services (DS) 
   field in the IP header and the Per-Hop Behavior (PHB) as main 
   building blocks. Packets are handled at each node according to the 
   PHB indicated by the DS field in the message header.


   The Diffserv architecture does not specify any way for devices 
   outside the domain to dynamically reserve resources or receive 
   indications of network resource availability.  In practice, 
   service providers rely on subscription-time Service Level 
   Agreements (SLAs) that statically define the parameters of the 
   traffic that will be accepted from a customer.


   In [RMD], RMD was introduced as a possible method for dynamic 
   reservation of resources within a Diffserv domain.  It describes a 
   method for aggregating individual reservation request at the 
   ingress edge of the domain, two possible modes of operation for 
   internal nodes to admit aggregated requests (a stateless, 
   measurement-based mode, and a reduced-state reservation mode), and 
   a method to forward the original requests across the domain to the 
   egress edge and on.


   This document describes the RMD concept and specifies a data-path-
   coupled NSIS QoS Signaling Model that defines how the path-coupled 
   signaling provided by the NSIS QoS-NSLP (Next Steps In Signaling 
   Quality of Service ¡ NSIS Signaling Layer Protocol) can be used to 
   support RMD.  The RMD QoS Signaling Model uses the QoS-NSLP [QoS-
   NSLP] and the NTLP (NSIS Transport Layer Protocol) [NTLP] that are 
   being standardized by the NSIS working group. 


   The Quality of Service NSIS Signaling Layer Protocol (QoS-NSLP) 
   establishes and maintains states at nodes along the path of a data 
   flow for the purpose of providing or querying forwarding resources 
   for that flow [QoS-NSLP].  In QoS-NSLP the signaling is 
   independent of the underlying QoS model; it can signal for any QoS 
   provisioning method or QoS architecture, such as Diffserv 
   [RFC2475] or IntServ [RFC1633].  The method by which the protocol 
   signals for a specific QoS Model is called QoS Signaling Model.  A
   QoS Signaling Model defines specific QSpec objects, which are 
   carried in QoS-NSLP messages.  QSpec objects include QoS 
   descriptors and control information.  A QoS Signaling Model also 
   describes how QSpecs are processed.  More information on QoS 
   Models, QoS signaling models and QSpec is provided in the 
   Appendix.



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   In the RMD QoS signaling model, the edges of the Diffserv domain 
   support both the NSIS stateful and stateless/reduced state 
   operations, while the interior routers in the Diffserv domain 
   support only the NSIS stateless/reduced state operation.  Only 
   routers at the edges of a Diffserv domain support the QoS-NSLP 
   stateful operation.  Internal routers support either the QoS-NSLP 
   stateless operation, or a reduced-state operation with coarser 
   granularity than the edge nodes (e.g., per PHB).



2. Terminology


   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL 
   NOT", "SHOULD, "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" 
   in this document are to be interpreted as described in RFC 2119.



3. Overview of RMD QoS Model and QoS Signaling Model


3.1. RMD QoS Model


   The dynamic Diffserv QoS signaling model can be realized by using 
   the original concept of Resource Management in Diffserv (RMD) 
   framework [RMD].  In RMD, scalability is achieved by separating a 
   complex reservation mechanism used in edge nodes of a Diffserv 
   domain from a much simpler reservation mechanism needed in the 
   interior nodes.  In particular, it is assumed that edge nodes of a 
   Diffserv domain support per-flow QoS states in order to provide 
   QoS guarantees for each flow.  Interior nodes use only one 
   aggregated reservation state per traffic class or no states at 
   all.  This solution allows fast processing of signaling messages 
   and makes possible to handle large number of flows in the interior 
   nodes.  In this way, the RMD concept optimizes the NSLP/NTLP 
   functionality and processing. 


   In RMD two basic operation modes are described: a measurement 
   based admission control and a reservation based admission control. 
   The measurement-based algorithm uses the requested and available 
   resources as input to query the aggregated reservation state per 
   traffic class in the interior nodes.  The advantage of measurement 
   based resource management protocols is that they do not require 
   explicit reservation or release.  Moreover, when the user traffic 
   is variable, measurement based admission control could provide 
   higher network utilization than, e.g., peak-rate reservation. 
   However, this requires more complex implementation in interior 
   nodes and introduces an uncertainty of the availability of the 
   resources.  In case of the reservation-based method, each node in 
   the domain maintains one reservation state per traffic class. The 
   reservation is done in resource units. These resources are 
   requested dynamically per PHB and reserved on demand in all nodes 
   in the communication path from an ingress node to an egress node.



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3.2. RMD QoS Signaling Model Overview


   We denote the dynamic Diffserv QoS signaling model, which is based
   on the RMD concept, the RMD QoS signaling model.  The RMD QoS 
   signaling model supports both measurement- and reservation-based 
   admission control. In the first case QoS-NSLP states do not need 
   to be refreshed, therefore it is a stateless operation mode, while
   the reservation based methods is a reduced state operation mode.


   The RMD QoS Signaling Model uses a simple, hop-by-hop signaling 
   mechanism. When a new flow arrives with some requested resources 
   (typically bandwidth), a message indicating the required resources 
   is sent along the data path. Every node, one after the other, 
   checks the available resources on the data path of the flow with 
   either the reservation-based or the measurement-based method.  If 
   an intermediate node cannot accommodate the new request, it 
   indicates it by marking a single bit in the message.


   In the simplest case the domain wherein the RMD QoS signaling 
   model is applied is identical to a Diffserv administrative 
   domain.  However, the protocol can be extended for multiple domain
   as well.  The boundary nodes of the domain are NSIS aware edge 
   nodes (QNF ingress and QNF egress edges) and the interior nodes 
   are NSIS aware interior nodes (QNF interior).  The RMD QoS 
   Signaling Model uses the stateless/reduced state operation mode 
   defined in QoS-NSLP. 


  |------|   |-------|                           |------|   |------|
  | e2e  |<->| e2e   |<------------------------->| e2e  |<->| e2e  |
  | QoS  |   | QoS   |                           | QoS  |   | QoS  |
  |      |   |-------|                           |------|   |------|
  |      |   |-------|   |-------|   |-------|   |------|   |      |
  |      |   | local |<->| local |<->| local |<->| local|   |      |
  |      |   | QoS   |   |  QoS  |   |  QoS  |   |  QoS |   |      |
  |      |   |       |   |       |   |       |   |      |   |      |
  | NSLP |   | NSLP  |   | NSLP  |   | NSLP  |   | NSLP |   | NSLP |
  |st.ful|   |st.ful |   |st.less|   |st.less|   |st.ful|   |st.ful|
  |      |   |       |   |red.st.|   |red.st.|   |      |   |      |
  |      |   |-------|   |-------|   |-------|   |------|   |      |
  |------|   |-------|   |-------|   |-------|   |------|   |------|
  ------------------------------------------------------------------
  |------|   |-------|   |-------|   |-------|   |------|   |------|
  | NTLP |<->| NTLP  |<->| NTLP  |<->| NTLP  |<->| NTLP |<->|NTLP  |
  |st.ful|   |st.ful |   |st.less|   |st.less|   |st.ful|   |st.ful|
  |------|   |-------|   |-------|   |-------|   |------|   |------|
    QNI         QNF        QNF         QNF          QNF       QNR
   (end)  (ingress edge)(interior)  (interior) (egress edge)  (end)


      st.ful: statefull, st.less: stateless
      st.less red.st.: stateless or reduced state


   Figure 1   Protocol model of stateless/reduced state operation


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   The protocol model of the RMD QoS Signaling Model is shown in 
   Figure 1.  Consider an end-to-end QoS signaling model, i.e., 
   Intserv, in which NF nodes between End and Edge nodes install and 
   maintain per-flow QoS-NSLP states. In the Edge node of the 
   Diffserv domain, the end-to-end QoS-NSLP messages trigger the 
   generation of local dynamic Diffserv QoS-NSLP messages. The QSpec 
   of the end-to-end QoS-NSLP message is translated into RMD QSpec. 
   The original QoS-NSLP messages are sent directly to the next NTLP 
   stateful node, e.g. to the egress edge node. The local QoS-NSLP 
   messages are processed and interpreted in all interior NSLP 
   routers along the path, hop-by-hop, up to the egress edge node. 



4. RMD QoS Signaling Model detailed description


   This section describes the RMD QoS signaling model in details. 
   Particularly, we explain the role of stateless and reduced-state 
   QNEs, define the QSpec Object, the format of QoS NSLP messages, 
   how QSpecs are processed and used, and the protocol operation. 



4.1. Role of QoS NSLP Entities (QNEs)


   Edge nodes of an RMD domain can support both NSIS operation modes, 
   i.e., stateful and stateless/reduced state operation modes.  As 
   NSIS stateful nodes the edge nodes can store and administrate QoS-
   NSLP and NTLP states.  The interior nodes are either completely 
   stateless, i.e., they are not supporting any QoS-NSLP or NTLP 
   states as for measurement-based operation, or they are reduced 
   state nodes, i.e., they do not store NTLP states but they store 
   per PHB aggregated QoS-NSLP states as in reservation-based 
   operation.


   Note that the RMD domain may contain interior nodes that are not 
   NSIS aware nodes. Furthermore, some of these NSIS unaware nodes 
   may be used for measuring the traffic congestion level on the data 
   path.  These measurements, however, can be used by the RMD QoS 
   signaling model in the severe congestion operation (see Section 
   4.5.2.3).



4.2. Qspec Definition


   This section describes the Qspec that is used by the RMD QoS 
   signaling model.  There are two types of QSpec parameters: QoS 
   Descriptors, and Control Information. RMD QSpec parameters are 
   defined in [RMD], and will be updated in line with QSpec Template 
   draft [QSM-T].






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4.2.1. RMD QoS descriptors


   <bandwidth>:
   This parameter specifies the resources to be reserved in the nodes
   along the data path.  It can be number of resource units or 
   bandwidth. Bandwidth can be peak bandwidth, average bandwidth or 
   even effective bandwidth, depending on the implementation. The 
   default interpretation of this field is peak bandwidth. 


   <PHB>:
   This parameter specifies the traffic class for which resources 
   should be reserved


   Both these QoS descriptors are immutable and of the type "QoS 
   desired".



4.2.2. RMD control information 


   <M Bit>:
   In case of unsuccessful reservation in an interior QNF, this QNF 
   sets the M bit in order to notify the egress QNF. 


   <Hop Count>:
   The Hop Count is set to zero when a RESERVE message enters a 
   domain and increased by one at each interior QNF. However when a 
   QNF is reached that does not have sufficient resources to admit 
   the reservation, the M Bit is set, and the Hop Count value is 
   frozen. Hence the Hop Count counts the number of hops where the 
   reservation was successful.  In case of an unsuccessful 
   reservation the M Bit is set, and the egress QNF reacts by sending
   a RESPONSE message containing the Hop Count to the ingress QNF.  
   The ingress QNF uses the Hop Count value to remove the unnecessary
   reservations by an explicit tearing RESERVE message to the nodes 
   along the path where the reservation has already been made. 


   <S Bit>:
   In case of a route change refreshing RESERVE messages follow the 
   new data path, and hence resources are requested there.  However, 
   on the new path resources may not be sufficient to accommodate the
   new traffic. Congested interior nodes should notify edge QNFs 
   about the congestion, in order to terminate some of the flows. 
   The notification of the egress QNF is carried out by marking 
   either the data packets with dedicated DSCPs or by setting the S 
   Bit indicating severe congestion in the refresh message.  The 
   egress QNF decides which flows should be terminated and sends a 
   Response message to the Ingress edge with the flow ID and 
   indicating the severe congestion. Since refresh messages are 
   usually sent less frequently than the data packets a more 
   efficient method for the notification is marking the data packets 
   by changing the DSCP field.  



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  More details on the required control information for the RMD QoS 
  signaling model will be provided in a future version of this 
  draft.



4.2.3. Mapping of QSpec parameters onto generic QSpec Parameters


To be provided in a future version of this draft.



4.3. Message format


   The format of the messages used by the RMD QoS signaling model 
   complies with the QoS-NSLP specification. As specified in [QoS-
   NSLP], for each QoS-NSLP message type, there is a set of rules for 
   the permissible choice of object types.  These rules are specified 
   using Backus-Naur Form (BNF) augmented with square brackets 
   surrounding optional sub-sequences. The BNF implies an order for 
   the objects in a message. However, in many (but not all) cases, 
   object order makes no logical difference.  An implementation 
   should create messages with the objects in the order shown here, 
   but accept the objects in any permissible order. More details on 
   the message formats will be provided in the future versions of this
   draft.



4.4. State management


   The way of how the QoS-NSLP states are created and managed is 
   specified in [QoS-NSLP].  This section will describe how the 
   reservation states Resource Management Function of the reduced 
   states nodes are created and maintained.  More details on the state 
   management in the reduced state will be provided in the future.



4.5. Operation and sequence of events


   This section describes the operation and the sequence of events in
   the RMD QoS signaling model. More details on the operation and the
   sequence of events will be provided in future versions of this 
   draft.  This operation is similar to the protocol operation 
   described in [RMD]. 


   The transport characteristics for the 'local' reservation model
   can be different from that of the end-to-end reservation model. 
   GIMPS can be used in a different way for the edge-to-edge and 
   hop-by-hop sessions, (i.e. sending of messages in datagram mode, 
   and not retaining optional path state, i.e., NTLP stateless mode).
   The reduced state reservation can be updated independently of the
   per-flow end-to-end reservations.




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4.5.1. Edge discovery and addressing of messages


   This section describes the egress edge discovery and the 
   addressing of the signaling messages. 


   Mainly, the egress edge discovery can be performed either by using
   the NTLP discovery mechanism or by configuration.  The addressing 
   of signaling messages depends on the used NTLP transport mode. 


   The RMD QoS signaling messages that are processed only by the edge 
   nodes use the peer-peer addressing of the NTLP connection mode 
   (C).  While the RMD QoS signaling messages that are processed by 
   all nodes of the Diffserv domain, i.e., edges and interior nodes, 
   use the end-end addressing of the NTLP datagram (D) mode. More 
   details on the egress edge discovery and the addressing of the 
   signaling messages will be provided in a future version of this 
   draft.



4.5.2. Basic unidirectional operation


   This section describes the basic unidirectional operation and 
   sequence of events of the RMD QoS signaling model.  The following 
   basic operation cases are distinguished, more details can be 
   found in [RMD]. 



4.5.2.1. Successful reservation


   This section describes the operation of the RMD QoS signaling  
   model where a reservation is successfully accomplished. 



4.5.2.2. Unsuccessful reservation


   This section describes the operation where a request for 
   reservation cannot be satisfied by the RMD QoS signaling model. 



4.5.2.3. Severe congestion


   This section describes the operation of the RMD QoS signaling 
   model where a severe congestion occurs within the Diffserv domain.
   Severe congestion is an undesirable event, e.g after re-routing, 
   where the resources are not enough to meet the required QoS for 
   all the flows along the new path, therefore one or more flows 
   should be terminated. Interior nodes notify edge nodes by data 
   marking or marking the refresh messages.  In order to eliminate 
   severe congestion the degree of overload can also be indicated, 
   e.g. by using proportional marking. 




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   Congestion can also occur in an interior node due to the 
   underestimation of the data traffic, inappropriate policer 
   settings, or due to the uncertainty introduced by the measurement 
   method. 


   Severe congestion function of RMD can be used for implementiong 
   a lightweight  measurement based admission control within a 
   Diffserv domain.  It is possible that not all the nodes along the 
   path implement and run admission control, only a few interior 
   nodes are responsible for admission control.  In these nodes there
   may be predefined thresholds that can be set for the different 
   PHBs.  If the threshold is exceeded refresh messages or the data 
   packets can be marked to indicate the high load of different 
   PHBs.



4.5.3. Basic bidirectional operation


   This section describes the basic bidirectional operation and 
   sequence of events in the RMD QoS signaling model.  Combined 
   sender-receiver initiated reservation cannot be done in the domain
   because upstream NTLP states are not stored in interior routers. 
   Therefore bi-directional operation can be performed by two sender-
   initiated reservations.  However, if the edge nodes are common for
   both upstream and downstream direcrions, RMD offers significant  
   optimization.  More details will be provided in the next version 
   of this draft.



5. Security Consideration


Future versions of this draft will describe the security 
considerations associated with the RMD QoS signaling model. 



6. IANA Considerations


If the document creates a new IANA registry, or reserves new 
values for an existing IANA registry, an IANA considerations 
section should be included, see RFC 2434.



7. Open issues


This section describes the open issues related to the RMD QoS 
signaling model. More details on open issues will be provided in a 
future version of this draft.







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8. Acknowledgments


The authors express their acknowledgement to people worked earlier on
the RMD concept: Z. Turanyi, R. Szabo, A. Csaszar, A. Takacs, G. 
Pongracz, O. Pop, V. Rexhepi, D. Partain, M. Jacobsson, S. Oosthoek, 
P. Wallentin.  
   


9. Authors' Addresses


   Attila Bader
   Traffic Lab
   Ericsson Research
   Ericsson Hungary Ltd.
   Laborc u. 1 H-1037
   Budapest Hungary
   EMail: Attila.Bader@ericsson.com


   Lars Westberg
   Ericsson Research
   Torshamnsgatan 23
   SE-164 80 Stockholm
   Sweden
   EMail: Lars.Westberg@ericsson.com


   Georgios Karagiannis
   University of Twente
   P.O. BOX 217
   7500 AE Enschede
   The Netherlands
   EMail: g.karagiannis@ewi.utwente.nl


   Cornelia Kappler
   Siemens AG
   Siemensdamm 62
   Berlin 13627
   Germany
   Email: cornelia.kappler@siemens.com


   Tom Phelan
   Sonus Networks
   EMail: tphelan@sonusnet.com












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10. References


   [RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.
   and W. Weiss, "An Architecture for Differentiated Services", RFC 
   2475, December 1998


   [RFC2638] Nichols K., Jacobson V., Zhang L. "A Two-bit 
   Differentiated Services Architecture for the Internet", RFC 2638,
   July 1999


   [RFC1633] Braden R., Clark D., Shenker S., "Integrated Services in 
   the Internet Architecture: an Overview" RFC 1633


   [QoS-NSLP] Bosch, S., Karagiannis, G. and A. McDonald, "NSLP for 
   Quality-of-Service signaling", draft-ietf-nsis-qos-nslp-03 (work 
   in progress), May 2004.


   [QSM-T] Ash, J., Bader, A., Kappler C., "QoS-NSLP QSpec Template" 
   draft-ash-nsis-nslp-QSpec-00 (work in progress), February 2004.


   [RMD] Bader, A., "RMD (Resource Management in Diffserv) QoS-NSLP 
   model", draft-bader-rmd-qos-model-00 (work in progress), 
   February 2004.


   [QSM-CL] Kappler, C. "A QoS Model for signaling IntServ Controlled-
   Load Service with NSIS", draft-kappler-nsis-qosmodel-
   controlledload-00 (work in progress), February 2004.



11. Appendix: QoS models, QoS Signaling Models and QSpecs


   This section gives a description of QoS models, QSMs and QSpecs 
   and explains what is the relation between them. Once these 
   descriptions are contained in a stable form in the appropriate IDs
   (mainly QoS NSLP [2] and QSpec Template[3]) this Appendix will be 
   removed. 


   QoS NSLP is a generic QoS Signaling Protocol that can signal for 
   many QoS Models.  A QoS Model is a particular QoS provisioning 
   method or QoS architecture such a IntServ Controlled Load, 
   Guaranteed Service, DiffServ or RMD. 


   The definition of the QoS Model is independent from the definition
   of QoS-NSLP. Existing QoS Models do not specify how to use QoS 
   NSLP to signal for them.  Therefore, we need to define the QoS 
   Signaling Models (QSMs), specific to each QoS Model, which 
   describes the QoS Model specific signaling functions.  In this 
   draft we defined the RMD QoS Signaling Model to signal for RMD. 
   Another QoS Signaling Model was defined for IntServ Controlled 
   Load in [7].




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   A QSM should include the following information (for an 
   illustration see this draft):


   - Role of QNEs in the QoS Model: 
   E.g. location, frequency, statefulness...


   - QSpec Definition: 
   QoS NSLP carries QSM-specific information in the QSpec object. The
   QSpec is opaque to QoS NSLP.  It contains the QoS Signaling Model 
   specific control information and QoS description parameters. QoS 
   description parameters can have sub-objects e.g. corresponding to
   the TSpec, RSpec and AdSpec objects specified in RSVP.  QSM should
   specify QSpec.


   - Message Format 
   Objects to be carried in RESERVE, QUERY RESPONSE and NOTIFY 
   messgages


   - State Management
   It describes how QSpec info is treated and interpreted in the 
   Resource Management Function and QSM specific processing, e.g. 
   admission control, scheduling, policy control, QoS parameter 
   accumulation (e.g. delay)à


   - Operation and Sequence of Events
   Usage of QoS-NSLP messages to signal the QoS model.




Intellectual Property Statement


   Ericsson will issue an IPR statement about RMD.


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   Copies of IPR disclosures made to the IETF Secretariat and any 
   assurances of licenses to be made available, or the result of an 
   attempt made to obtain a general license or permission for the use
   of such proprietary rights by implementers or users of this 
   specification can be obtained from the IETF on-line IPR repository
   at http://www.ietf.org/ipr.





Bader, et al.                                                [Page 13]


INTERNET-DRAFT                                 RMD QoS signaling model



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Bader, et al.                                                [Page 14] 

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