QoS Implications of NGN Architectures

Transcription

1 QoS Implications of NGN Architectures Preliminary Conclusions from STF 363 ETSI STQ Workshop 1-2 July ETSI, Sophia Antipolis, France Joachim Pomy, Consultant STF 363 Leader ETSI All rights reserved

2 Agenda STF-363: The Project Stakeholders Services in NGN from a Users' Perspective Changes in Users' Behaviour Market Mechanisms Standardization Gaps Regulatory Aspects Real World Conclusions 2

3 STF-363: The Project Specialist Task Force 363, a project team: Pietro Schicker (Swisscom, Switzerland) Peter Pocta (University of Zilina, Slovakia) Joachim Pomy (Telecommunications & Int'l Standards, Germany) QoS implications of NGN architectures Study of real world architectures Interviews of Network Operators Detailed technical questionnaire Direct interviews & personal consultation Interviews with selected manufacturers Consideration of possible regulatory aspects Conclusions Current QoS "landscape" Need for new standards to enable better QoS 3

4 Stakeholders Network operators and service providers Want confirmation that existing or planned NGN architectures will lead to satisfactory QoS across multiple interconnected NGNs. Want to learn which improvements in architectures may be needed Users Will benefit from the ability of network operators and service providers to provide guaranteed QoS voice services on NGNs Manufacturers Want to know that currently available terminals are suitable for use with NGN services Confirmation of network architecture suitability will give guidance on the required performance of routers and media gateways. Regulators Want to have a better assurance that users are not adversely affected as PSTN services migrate to NGN 4

5 Services in NGN from a Users' Perspective New services introduced in NGN IPTV - more to come, but no intent to standardize! Migration of existing services from PSTN to NGN Voice Telephony Facsimile ISDN clearchannel bearer service End-to-End QoS as perceived by the user Level of QoS Contracted? - check your contract! Regulated? - rely on market forces! Delivered? - how can the user measure! Stability, availability? - and more aspects! QoS for services migrated to NGN (over IP) not (yet) the same QoS as in PSTN (over TDM) 5

6 Changes in Users' Behaviour Users tend to be much more reluctant to accept lower quality This is quoted frequently True for some sorts of social calls Definitively NOT true for sensible business calls Does it help network operators when defining QoS for their network? High quality has to be provided when demanded by business customers or other sensible clients But the distribution of quality acceptance over time and areas cannot be matched with the occurrence of impairments in the network Not really useful for designing networks Users switch between different communication devices Wireline, wireless, PC, PDA etc Depending on place, task, purpose And depending on QUALITY 6

7 Market Mechanisms Forces of the Market will bring users into a position where they can obtain the end-to-end QoS they wish to perceive Has been postulated for a long time in Europe Has been proven to be more than questionable Mostly, contracts between users and network operators have a longterm binding character do not contain any QoS provisions Currently, traditional Telcos have no incentive to provide high end-to-end QoS for their NGN customers Number of customers remains stable In parallel the commercial company value In contrast are Internet based communication service providers Receive their revenue not directly from users But by other business models which rely on a high (and increasing) number of users of the service every day Customers not satisfied with end-to-end QoS will stop using the service Consequently the number of customers decreases immediately and so the company value Thus the incentive to offer high end-to-end QoS to the user is extremely high. 7

8 Standardization Gaps (1) Objective Performance Indicator for Interaction Quality (IQ) Interaction Quality as perceived by the user depends on delay & task In NGN network operators have no real control of either Delay is a technical term Communication task are difficult to model Network operators want to know whether their customers are satisfied with the possibility to interact in a call Low delay as in PSTN implies user satisfaction with IQ But high delay does not automatically imply user dissatisfaction An indicator could help operators to determine critical areas in their network Interconnection issues with other operators Efficiently launch measurement campaigns Inclusion of QoS Parameters of IP Terminals in User Profiles Could help to improve network adaptation to terminals Increase operators knowledge about terminal parameters In conjunction with "QoS continuity" proposed by STF-360 8

9 Standardization Gaps (2) Inclusion of QoS Parameters of IP Terminals in User Profiles Could help to improve network adaptation to terminals Increase operators knowledge about terminal parameters In conjunction with "QoS continuity" proposed by STF-360 IP-based Home Gateways and Other Media Gateways New Standard on Voice Transmission Requirements from a QoS Perspective as perceived by the User Following the same concept as the 4 VoIP Standards (ES , ES , ES & ES ) Definition of high voice quality device instead of minimum quality Analogue Loop in IP terminals and gateways for delay testing Remotely controlled from the network Not seen by the customer 9

10 Regulatory Aspects Satisfactory Telecommunications Quality vital for economy Businesses rely on it Users prefer to pay for satisfactory services only high quality could be an incentive to spend more money Mandatory reporting of QoS figures Already started in some EU countries Must be improved to be meaningful for users Terminate Early (TME) options for the customer contract New standards (?) for users to proof the level of QoS perceived Appropriate regulatory interventions in cases where customers of NGN operators are extremely unsatisfied with the end-to-end QoS provided to them 10

11 Preliminary Conclusions Many operators show a high interest in providing good end-to-end QoS to their customers Discrepancy between intention and ability Large difficulties for operators to collect all QoS relevant information No proper end-to-end transmission planning for NGN is in place Operators do not adhere to a common set of requirements and/or standards in order to obtain end-to-end QoS Obtaining end-to-end QoS between users of different operators' NGNs needs further investigation / standardization. In some countries regulation is in place for end-to-end quality Based on E-model or on assumption about delay After migration to NGN PSTN services no longer work as expected ISDN clearmode V.90 / V.34 Modems Facsimile via G.711 channels Facsimile via T.38 with compatibility / version problems G.8261 (Synchronous Ethernet) being deployed does it solve the problems? 11

12 Contact: Joachim Pomy Telecommunications & Int'l Standards 12