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原作者： Rafal Stankiewicz,Piotr
Cholda,and Andrej Jajszczyk,AGH
University of Science and Technology
汇报人 : 马林

• What is QoX
• QoX stands for:
– QoS: Quality of Service
– CoS: Classes of Service
– GoS: Grade of Service
– QoR: Quality of Resilience
– QoE: Quality of Experience

• Three levels of QoS
• Intrinsic QoS
 The ability of a network to provide the functions Related to communica-
Tion between users
• Perceived QoS
 QoS requirements of the customer
 QoS offered by the provider
 QoS achieved by tne provider
 QoS perceived by the customer

• ITU-T
 six classes:1.Real-time,jitter sensitive , high interaction;2.Realtime,jitter sensitive,interactive;3.Transaction data , highly interactive;4.transaction data , interactive;5.Low loss only;6.Traditional applications of default IP network.
• IEFT
 The requirement of each service class are described qualitatively as a tolerance to packet loss , delay and jitter.
 There is no strict values or bounds for the parameters per CoS.

• 3GPP
 Four classes:1.Conversational;2.streaming;3.Interactive;4.Background
• IEEE:

• GoS
 Applies to circuit switched networks and describes all phenomena occurring during connection setup , release and maintenance.
 Parameters : 1.connection set up delay;2.probability of end-to-end blocking;3.delay in authentication;4.probability of breaking an active connection.
QoR
 Network survivability against failures
 Parameters: the probability that a service is operational.

• Definition:
 The overall acceptability of an application or service , as perceived subjectively by the end-user
• Factors influencing QoE

• QoE Evaluation Method
 Subjective testing
 Objective testing
 Network planning models(belong to Objective testing)