IP Performance Specifications Progress and Next Steps
July 11, 2002
Al Morton
End-to-End IP Network Performance
IP Network Cloud
NI
TE
NI
GW
GW
...
GW
GW
. . . GW
GW
LAN
TE
LAN
Network Section
Customer Installation
Network Section
Network Section
End-End Network (Bearer Service QoS)
Customer Installation
User-to-User Connection (Teleservice QoS)
TE Terminal Equipment
GW
Gateway
Router
Protocol Stack
NI
Network Interface
•Growth of real-time/CBR application use on IP nets
•VoIP, Multi-Media Conferencing, Streaming...
•New applications require stricter performance
Al Morton
Page 2
IP Packet Transfer Specifications
Delay Variation
IETF IPPM RFCs
2330
2330, I-D NPM w
Periodic Streams
2680
2679 (1-way)
2681 (Round Trip)
I-D on IPDV
Availability
2678
Framework
Sampling
Loss
Delay
Al Morton
ITU-T Recs.
I.380 cl 1 thru 5
(future work in
SG4 ?)
I.380 cl 5.5.6
I.380 cl 6.2
I.380 App I, Y.1540
cl 6.2.2
Y.1540 cl 7
Page 3
Evolution of IPPM and Question 6/13
 New RFCs
 Loss Patterns
 Bulk Transfer Capacity
 Current I-Ds
 Packet Reordering
 Active Meas. Protocol Req.
 IPPM MIB
 Newly Chartered Work on
 Link Bandwidth Capacity
Al Morton
 Performance Objectives
 Y.1541 (May 2002), six QoS
Classes
 Suggest QoS Signaling
Support/Methods
 Parameter Revisions
 Y.1540 (Nov 2002)
 “other” Packet Transfer
 MPLS?
Page 4
Y.1541 "Provisional IP QoS Classes”
Network
Performance
Parameter
IPTD
IPDV
IPLR
IPER
Nature of Network
Performance
Objective
Upper bound on the
mean IPTD
Upper bound on the
1-10 -3 quantile of
IPTD minus the
minimum IPTD
Upper bound on the
packet loss
probability
Upper bound
Class 0
Class 1
Class 2
Class 3
Class 4
Class 5
Unspecified
100ms
400 ms
100ms
400ms
1s
U
50ms
50 ms
U
U
U
U
1*10-3
1*10-3
1*10-3
1*10-3
1*10-3
U
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.
Al Morton
Page 5
Viewpoints of QoS
CUSTOMER
Customer’s
QOS
Requirements
QOS
Perceived
By Customer
SERVICE
PROVIDER
QOS Offered
By
Provider
QOS
Achieved by
Provider
From G.1000, Communications quality of service: A framework and definitions
Al Morton
Page 6
Elements of Service Provider’s IP QoS View
QoS Framework
Std IP Perf Parameters
Std IP QoS Classes
SLAs
SERVICE
PROVIDER
QOS Offered
By
Provider
Objectives
Reality
QOS
Achieved by
Provider
Al Morton
QoS Mechanisms
Std Active Meas.
Sampling Methodologies
Passive Monitoring
Page 7
QoS Agreements - Today and Tomorrow
Published
Req.
Reqmnts.
IS Manager
Design& Eng.
Objectives
Reality
Al Morton
Cooperating
Network
Request
ACK/REJ/Mod
Users
Provisioning
QoS Mech.
Apps
Reports
(SLAs)
Page 8
QoS Agreements - Viewed as 3 Entities
User
Requirements
IS Manager/
Requirements
Network:
Published
Req.
...
Design& Eng.
Objectives
Reality
Reports
Provisioning
QoS Mech.
Applications
Reports
(SLAs)
Perceived
QoS
Al Morton
Page 9
QoS Agreements - Future
User
QoS
Requirements
Application
Request
ACK/REJ/Mod
Application
Requirements
Cnfg.Choices
Objectives
Reality
Request
ACK/REJ/Mod
QoS Classes
& Decisions
Topo/Policy
Design/Eng.
Feedback
Provisioning
QoS Mech.
Monitoring
Reports
(SLAs)
Perceived
QoS
Al Morton
Network(s)
...
Page 10
Next Steps
 Define Process and Methods to ACHIEVE e-e Objectives
 Begin with Single networks and Static Agreements
 Static, with Two or Three Networks
 difficult with more networks (see draft M.2301)
 Build-in Flexibility (not too much)
 Network to Network Signaling for QoS
 In the “Oracle” model, each network has an entity with specific
knowledge and control capabilities. These entities use a signaling
protocol to communicate efficiently across network boundaries
(accept/reject/modify requests).
 Standardize Delay Variation Definitions
 Revisit IP Service Availability Function Definition
 Wide range of sensitivities across user applications
Al Morton
Page 11