The correct testing method is vital for the evaluation of VoIP services

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "The correct testing method is vital for the evaluation of VoIP services"

Transcription

1 The correct testing method is vital for the evaluation of VoIP

2 No part of this brochure may be copied or published by means of printing, photocopying, microfilm or any other process whatsoever without prior permission in writing by Nextragen GmbH; nor may it be stored, processed, reproduced or distributed using electronic systems. Kindly note that the used designations and brand names of the respective companies are subject to trade or brand mark protection or are protected by patents. Copyright: 2012 Nextragen GmbH Stand: 02/2012 Publisher: Nextragen GmbH Lise-Meitner-Str Flensburg Germany 2

3 Management Summary TraceSim evaluates the speech quality of VoIP calls based on several testing methods. These methods are very different from each other and are suitable for differing purposes. In addition, not every method responds to the individual requirements of the respective testing situation. This paper will discuss the basics and fundamental differences of two of the most common measurement methods: E-model and PRESQ algorithm. Generally, all testing methods evaluate the speech quality of VoIP connections on a scale of one (poor quality) to five (excellent quality). This system is called Mean Opinion Score (MOS). MOS is defined in the ITU-T standard P.800. However, an MOS value stated in a testing protocol or in a Service Level Agreement (SLA) can only deliver an interpretable result of the actual network quality if the underlying testing method is known. Depending on the method various MOS values can be measured. For instance, MOS values resulting from measurements according to the E-model and the PESQ algorithm cannot be compared with each other. As a result, it should be made clear which testing method the MOS value is based on, which can be expressed as follows: MOS E-model = MOS value according to the E-model MOS PESQ = MOS value according to PESQ The ITU standard goes even further to define in more detail the characteristics of the MOS values. In practice and for testing purposes, however, information about the respective testing method used suffices. First, let us turn out attention to the E-model. The E-Model Considers Packet Parameters Only The E-model is defined in the ITU standard Rec. G.107. During E-model tests, the data streams of the RTP packets (RTP streams) are captured and evaluated according to the behaviour of the packet parameters. Such parameters include: Packet loss: packets which get lost during transportation; Jitter: average deviation from the network mean latency; Delay: delay between the sender and the receiver; Codec: VoIP codec used to decode the language. The four parameters are subsequently provided to the E-model algorithm which calculates the MOS value of the RTP stream. The E-model checks whether all packets of the respective RTP stream have arrived. In simple network setups (with one media gateway), this allows for an interpretable network quality evaluation. For instance, if the testing results of a simple LAN deliver negative MOS values, the RTP streams are obviously corrupted and the desired speech quality cannot be produced. Also, a series of subsequent tests can show whether the quality has improved or not. Yet, this testing method quickly comes up against limiting factors. The E-model can only measure the quality in LANs, but not the content of the RTP packets which carry important information, such as language. Neither can the E-model deliver proper MOS values when testing across various network segments. Figure 1 illustrates the methodological limitations of the E-model. The example shows a typical company network with two VoIP network locations covering three network segments (IP - ISDN/WAN - IP) which are connected via gateways. Such gateways convert VoIP packets into ISDN packets and vice versa. 3

4 Figure 1: The E-model can only measure erroneous RTP packets within the respective network segment. Errors which have been inherited from one segment to another are ignored since the correction packets do not carry information about the language (here: packet loss). MOS values of the VoIP quality based on the E-model method do not provide any information about the end-to-end (covering all three segments) network quality. Network A and network B must be measured separately and will deliver different MOS values. Codec errors in the gateways and transmission errors in the ISDN network cannot be identified. Reasons include during packet conversion from one format into the other the time stamps are newly generated, packet errors (jitter or placket loss) are reset. This measurement method considers packet layers, yet no packet content (the actual language). E-model tests are only carried out from one measurement point to another measurement point. Consequently, the E-model fails to calculate the end-to-end quality values and cannot deliver a complete evaluation of the entire network setup. If instead of the ISDN connection, a WAN is installed between network A and network B, network providers will often introduce a codec conversion, e. g. from G.711 to G.729, to save bandwidth. This conversion divides the network again into three segments. If such network setup is tested according to the E-model, no values about the end-to-end network quality can be delivered. Instead, the measured MOS values can only serve to determine the quality of the individual segments. The problem remains: inherited errors are ignored in the evaluation of the subsequently measured network segments. PESQ Takes The Transmitted Language Into Account The PESQ algorithm is based on the specification defined in the ITU-T standard Re. P.862. The PESQ algorithm uses the language signals in order to calculate the MOS values. A reference signal is compared with the received signal sent across the entire network. This method takes into account the language quality between the sender and the receiver on an end-to-end basis. 4

5 Figure 2: MOS values based on PESQ. Changes and quality impairments at the receiver s end are identified by comparing the reference signal with the received signal. The MOS value delivers an end-to-end evaluation of the speech quality of the entire network. The PESQ algorithm measures the speech signal which means that any signal changes or errors in the transmission path are registered. Compared to the E-model (which only provides information about packet transportation errors (e.g. packet loss, jitter, etc.) within a network segment), the PESQ algorithm evaluates the entire network from end to end. Also, quality impairments (errors occurring during codec conversion, e.g. from IP to ISDN), resulting from the conversion of codecs at network gateways are measured. Conclusion The difference between the two measuring methods lies in the parameters which are reflected in the MOS values. The E-model only refers to the characteristics of RTP packets. PESQ, on the other hand, calculates MOS values based on real speech signals. In particular, when a communication path is made up of several segments including media gateways, the E-model delivers ambiguous statements which can lead to a misinterpretation of the actual speech quality. Yet, the E-model is used on most of the measurement solutions which is due to two reasons: in simple setup the E-model delivers MOS values which sufficiently reflect the actual speech quality, the algorithm can be implemented into measurement devices whilst saving on licenses (other methods require licenses). However, as learned earlier on, stating of MOS values without indication on which testing method (E-model or PESQ) the values are based, does not provide any information about the actual network quality. Today, PESQ is the market standard by providers of professional measurement solutions. Due to recent advances and developments in the IP sector, the PESQ algorithm no longer covers all relevant network parameters. In 2011 the ITU introduced a new recommendation: ITU-T Rec. P.863 named Perceptual Objective Listening Quality Analysis (POLQA). POLQA upgrades PESQ and adds significant new capabilities for wideband and super-wideband ( Hz) voice signals along with support for most recent voice coding and VoIP transmission technologies. POLQA is suited to evaluate, optimize and monitor the voice quality of next-generation networks. In the course of the expansion of Next Generation Networks over the next few years, POLQA will become more and more relevant for providers of fixed IP networks and of wireless networks. 5

6 About Nextragen Nextragen GmbH is specialised in the development of Monitoring, Analysing and Testing software for VoIP/ video solutions to ensure the quality of End2End (QoS, QoE) for Next Generation Networks and triple-play. The company was founded in 2009 and is based in the Flensburg in Germany. Nextragen s customers, including carriers, enterprise customers and telecommunication businesses, make use of our solutions to monitor, analyse and test the quality, reliability and availability of VoIP and video applications. Nextragen s products, solutions and are 100% made in Germany and are distributed globally through certified partners. For more information, visit the company website at 6

7 Nextragen GmbH Lise-Meitner-Str Flensburg Telefon: Fax: Errors and omissions expected. 7

TraceSim 3.0: Advanced Measurement Functionality. of Video over IP Traffic

TraceSim 3.0: Advanced Measurement Functionality. of Video over IP Traffic TraceSim 3.0: Advanced Measurement Functionality for Secure VoIP Networks and Simulation of Video over IP No part of this brochure may be copied or published by means of printing, photocopying, microfilm

More information

CUSTOMER BENEFITS OF NEXTRAGEN PRODUCTS. Lise-Meitner-Str. 2 24941 Flensburg Germany Tel: +49 (0) 461 9041 4440 www.nextragen.de

CUSTOMER BENEFITS OF NEXTRAGEN PRODUCTS. Lise-Meitner-Str. 2 24941 Flensburg Germany Tel: +49 (0) 461 9041 4440 www.nextragen.de CUSTOMER BENEFITS OF NEXTRAGEN PRODUCTS Lise-Meitner-Str. 2 24941 Flensburg Germany Tel: +49 (0) 461 9041 4440 www.nextragen.de Solutions for Carriers Testing: Nextragen delivers security throughout the

More information

A Generic Algorithm for Midcall Audio Codec Switching

A Generic Algorithm for Midcall Audio Codec Switching A Generic Algorithm for Midcall Audio Codec Switching Haytham Assem, Mohamed Adel, Brendan Jennings, David Malone, Jonathan Dunne and Pat O Sullivan TSSG, Waterford Institute of Technology,Ireland Hamilton

More information

Active Monitoring of Voice over IP Services with Malden

Active Monitoring of Voice over IP Services with Malden Active Monitoring of Voice over IP Services with Malden Introduction Active Monitoring describes the process of evaluating telecommunications system performance with intrusive tests. It differs from passive

More information

VoIP QoS. Version 1.0. September 4, 2006. AdvancedVoIP.com. sales@advancedvoip.com support@advancedvoip.com. Phone: +1 213 341 1431

VoIP QoS. Version 1.0. September 4, 2006. AdvancedVoIP.com. sales@advancedvoip.com support@advancedvoip.com. Phone: +1 213 341 1431 VoIP QoS Version 1.0 September 4, 2006 AdvancedVoIP.com sales@advancedvoip.com support@advancedvoip.com Phone: +1 213 341 1431 Copyright AdvancedVoIP.com, 1999-2006. All Rights Reserved. No part of this

More information

Troubleshooting Common Issues in VoIP

Troubleshooting Common Issues in VoIP Troubleshooting Common Issues in VoIP 2014, SolarWinds Worldwide, LLC. All rights reserved. Voice over Internet Protocol (VoIP) Introduction Voice over IP, or VoIP, refers to the delivery of voice and

More information

Evaluating Data Networks for Voice Readiness

Evaluating Data Networks for Voice Readiness Evaluating Data Networks for Voice Readiness by John Q. Walker and Jeff Hicks NetIQ Corporation Contents Introduction... 2 Determining Readiness... 2 Follow-on Steps... 7 Summary... 7 Our focus is on organizations

More information

ETSI TS 101 329-2 V1.1.1 (2000-07)

ETSI TS 101 329-2 V1.1.1 (2000-07) TS 101 329-2 V1.1.1 (2000-07) Technical Specification Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); End to End Quality of Service in TIPHON Systems; Part 2: Definition

More information

Application Notes. Introduction. Contents. Managing IP Centrex & Hosted PBX Services. Series. VoIP Performance Management. Overview.

Application Notes. Introduction. Contents. Managing IP Centrex & Hosted PBX Services. Series. VoIP Performance Management. Overview. Title Series Managing IP Centrex & Hosted PBX Services Date July 2004 VoIP Performance Management Contents Introduction... 1 Quality Management & IP Centrex Service... 2 The New VoIP Performance Management

More information

R&S IP-GATE IP gateway for R&S MKS9680 encryption devices

R&S IP-GATE IP gateway for R&S MKS9680 encryption devices Secure Communications Product Brochure 0.00 R&S IP-GATE IP gateway for encryption devices R&S IP-GATE At a glance The R&S IP-GATE is an IP interface for the encryption device. Used with the, the R&S IP-GATE

More information

Traffic Characterization and Perceptual Quality Assessment for VoIP at Pakistan Internet Exchange-PIE. M. Amir Mehmood

Traffic Characterization and Perceptual Quality Assessment for VoIP at Pakistan Internet Exchange-PIE. M. Amir Mehmood Traffic Characterization and Perceptual Quality Assessment for VoIP at Pakistan Internet Exchange-PIE M. Amir Mehmood Outline Background Pakistan Internet Exchange - PIE Motivation Preliminaries Our Work

More information

Application Note. Pre-Deployment and Network Readiness Assessment Is Essential. Types of VoIP Performance Problems. Contents

Application Note. Pre-Deployment and Network Readiness Assessment Is Essential. Types of VoIP Performance Problems. Contents Title Six Steps To Getting Your Network Ready For Voice Over IP Date January 2005 Overview This provides enterprise network managers with a six step methodology, including predeployment testing and network

More information

Tech Note. Introduction. Definition of Call Quality. Contents. Voice Quality Measurement Understanding VoIP Performance. Title Series.

Tech Note. Introduction. Definition of Call Quality. Contents. Voice Quality Measurement Understanding VoIP Performance. Title Series. Tech Note Title Series Voice Quality Measurement Understanding VoIP Performance Date January 2005 Overview This tech note describes commonly-used call quality measurement methods, explains the metrics

More information

12 Quality of Service (QoS)

12 Quality of Service (QoS) Burapha University ก Department of Computer Science 12 Quality of Service (QoS) Quality of Service Best Effort, Integrated Service, Differentiated Service Factors that affect the QoS Ver. 0.1 :, prajaks@buu.ac.th

More information

QoS in VoIP. Rahul Singhai Parijat Garg

QoS in VoIP. Rahul Singhai Parijat Garg QoS in VoIP Rahul Singhai Parijat Garg Outline Introduction The VoIP Setting QoS Issues Service Models Techniques for QoS Voice Quality Monitoring Sample solution from industry Conclusion Introduction

More information

Application Notes. Introduction. Sources of delay. Contents. Impact of Delay in Voice over IP Services VoIP Performance Management.

Application Notes. Introduction. Sources of delay. Contents. Impact of Delay in Voice over IP Services VoIP Performance Management. Application Notes Title Series Impact of Delay in Voice over IP Services VoIP Performance Management Date January 2006 Overview This application note describes the sources of delay in Voice over IP services,

More information

Service resiliency and reliability Quality of Experience Modelling requirements A PlanetLab proposal. PDCAT'08 - Dunedin December 1-4, 2008

Service resiliency and reliability Quality of Experience Modelling requirements A PlanetLab proposal. PDCAT'08 - Dunedin December 1-4, 2008 PlaNetLab Options from Massey University Richard Harris Presentation Outline Service resiliency and reliability Quality of Experience Modelling requirements A PlanetLab proposal PDCAT'2008 Dunedin 2 (c)

More information

MultiDSLA. Measuring Network Performance. Malden Electronics Ltd

MultiDSLA. Measuring Network Performance. Malden Electronics Ltd MultiDSLA Measuring Network Performance Malden Electronics Ltd The Business Case for Network Performance Measurement MultiDSLA is a highly scalable solution for the measurement of network speech transmission

More information

VoIP Quality of Service:

VoIP Quality of Service: VoIP Quality of Service: Now that VoIP -- Voice over Internet Protocol, or "digital telephone," as it is sometimes rebranded -- has gone mainstream, it's important to have a solid understanding of the

More information

ZyXEL V100 Support Notes. ZyXEL V100. (V100 Softphone 1 Runtime License) Support Notes

ZyXEL V100 Support Notes. ZyXEL V100. (V100 Softphone 1 Runtime License) Support Notes ZyXEL V100 (V100 Softphone 1 Runtime License) Support Notes Version 1.00 April 2009 1 Contents Overview 1. Overview of V100 Softphone...3 2. Setting up the V100 Softphone.....4 3. V100 Basic Phone Usage.....7

More information

Application Note. Introduction. Definition of Call Quality. Contents. Voice Quality Measurement. Series. Overview

Application Note. Introduction. Definition of Call Quality. Contents. Voice Quality Measurement. Series. Overview Application Note Title Series Date Nov 2014 Overview Voice Quality Measurement Voice over IP Performance Management This Application Note describes commonlyused call quality measurement methods, explains

More information

Requirements of Voice in an IP Internetwork

Requirements of Voice in an IP Internetwork Requirements of Voice in an IP Internetwork Real-Time Voice in a Best-Effort IP Internetwork This topic lists problems associated with implementation of real-time voice traffic in a best-effort IP internetwork.

More information

Encapsulating Voice in IP Packets

Encapsulating Voice in IP Packets Encapsulating Voice in IP Packets Major VoIP Protocols This topic defines the major VoIP protocols and matches them with the seven layers of the OSI model. Major VoIP Protocols 15 The major VoIP protocols

More information

INTERNATIONAL TELECOMMUNICATION UNION 42!.3-)33)/. /&./.4%,%0(/.% 3)'.!,3

INTERNATIONAL TELECOMMUNICATION UNION 42!.3-)33)/. /&./.4%,%0(/.% 3)'.!,3 INTERNATIONAL TELECOMMUNICATION UNION )454 ( TELECOMMUNICATION (03/96) STANDARDIZATION SECTOR OF ITU 42!.3-)33)/. /&./.4%,%0(/.% 3)'.!,3 6)35!, 4%,%0(/.% 3934%-3!.$ 4%2-).!, %15)0-%.4 &/2,/#!,!2%!.%47/2+3

More information

An Introduction to VoIP Protocols

An Introduction to VoIP Protocols An Introduction to VoIP Protocols www.netqos.com Voice over IP (VoIP) offers the vision of a converged network carrying multiple types of traffic (voice, video, and data, to name a few). To carry out this

More information

Indepth Voice over IP and SIP Networking Course

Indepth Voice over IP and SIP Networking Course Introduction SIP is fast becoming the Voice over IP protocol of choice. During this 3-day course delegates will examine SIP technology and architecture and learn how a functioning VoIP service can be established.

More information

Speech Quality Measurement Tools for Dynamic Network Management

Speech Quality Measurement Tools for Dynamic Network Management Speech Quality Measurement Tools for Dynamic Network Management Simon Broom, Mike Hollier Psytechnics, 23 Museum Street, Ipswich, Suffolk, UK IP1 1HN Phone +44 (0)1473 261800, Fax +44 (0)1473 261880 simon.broom@psytechnics.com

More information

Fundamentals of VoIP Call Quality Monitoring & Troubleshooting. 2014, SolarWinds Worldwide, LLC. All rights reserved. Follow SolarWinds:

Fundamentals of VoIP Call Quality Monitoring & Troubleshooting. 2014, SolarWinds Worldwide, LLC. All rights reserved. Follow SolarWinds: Fundamentals of VoIP Call Quality Monitoring & Troubleshooting 2014, SolarWinds Worldwide, LLC. All rights reserved. Introduction Voice over IP, or VoIP, refers to the delivery of voice and multimedia

More information

Curso de Telefonía IP para el MTC. Sesión 2 Requerimientos principales. Mg. Antonio Ocampo Zúñiga

Curso de Telefonía IP para el MTC. Sesión 2 Requerimientos principales. Mg. Antonio Ocampo Zúñiga Curso de Telefonía IP para el MTC Sesión 2 Requerimientos principales Mg. Antonio Ocampo Zúñiga Factors Affecting Audio Clarity Fidelity: Audio accuracy or quality Echo: Usually due to impedance mismatch

More information

Quality Estimation for Streamed VoIP Services

Quality Estimation for Streamed VoIP Services Quality Estimation for Streamed VoIP Services Mousa Al-Akhras and Hussein Zedan STRL, De Montfort University, Leicester, UK makhras@dmu.ac.uk, hzedan@dmu.ac.uk http://www.cse.dmu.ac.uk/strl/index.html

More information

Receiving the IP packets Decoding of the packets Digital-to-analog conversion which reproduces the original voice stream

Receiving the IP packets Decoding of the packets Digital-to-analog conversion which reproduces the original voice stream Article VoIP Introduction Internet telephony refers to communications services voice, fax, SMS, and/or voice-messaging applications that are transported via the internet, rather than the public switched

More information

MOS Technology Brief Mean Opinion Score Algorithms for Speech Quality Evaluation

MOS Technology Brief Mean Opinion Score Algorithms for Speech Quality Evaluation MOS Technology Brief Mean Opinion Score Algorithms for Speech Quality Evaluation Mean Opinion Score (MOS) is commonly used to rate phone service speech quality, expressed on a scale from 1 to 5, where

More information

Monitoring VoIP Call Quality Using Improved Simplified E-model

Monitoring VoIP Call Quality Using Improved Simplified E-model Monitoring VoIP Call Quality Using Improved Simplified E-model Haytham Assem, David Malone Hamilton Institute, National University of Ireland, Maynooth Hitham.Salama.2012, David.Malone@nuim.ie Jonathan

More information

VoIP Monitor Professional

VoIP Monitor Professional Malden Electronics Speech Performance Assessment Product Brochure Brochure Issue 1 Malden Electronics Ltd. 2005 1 Product Overview is a software tool for non-intrusive assessment of speech quality and

More information

Speech Performance Solutions

Speech Performance Solutions Malden Electronics Speech Performance Solutions The REFERENCE for Speech Performance ssessment Speech Performance Solutions Issue 1.0 Malden Electronics Ltd. 2005 1 Product Overview Overview Malden Electronics

More information

Voice and Fax/Modem transmission in VoIP networks

Voice and Fax/Modem transmission in VoIP networks Voice and Fax/Modem transmission in VoIP networks Martin Brand A1Telekom Austria ETSI 2011. All rights reserved Name : Martin Brand Position: Senior IT Specialist at A1 Telekom Vice Chairman ETSI TC INT

More information

APTA TransiTech Conference Communications: Vendor Perspective (TT) Phoenix, Arizona, Tuesday, 3.19.13. VoIP Solution (101)

APTA TransiTech Conference Communications: Vendor Perspective (TT) Phoenix, Arizona, Tuesday, 3.19.13. VoIP Solution (101) APTA TransiTech Conference Communications: Vendor Perspective (TT) Phoenix, Arizona, Tuesday, 3.19.13 VoIP Solution (101) Agenda Items Introduction What is VoIP? Codecs Mean opinion score (MOS) Bandwidth

More information

Voice over Wi-Fi Voice Quality Assessment Test

Voice over Wi-Fi Voice Quality Assessment Test Location of Test: Azimuth Systems Headquarters, Acton, MA Date of Test: August 23 25, 2005 Voice over Wi-Fi Voice Quality Assessment Test A CT Labs Summary Report for Azimuth Systems and Empirix, Inc.

More information

VoIP Analysis Fundamentals with Wireshark. Phill Shade (Forensic Engineer Merlion s Keep Consulting)

VoIP Analysis Fundamentals with Wireshark. Phill Shade (Forensic Engineer Merlion s Keep Consulting) VoIP Analysis Fundamentals with Wireshark Phill Shade (Forensic Engineer Merlion s Keep Consulting) 1 Phillip D. Shade (Phill) phill.shade@gmail.com Phillip D. Shade is the founder of Merlion s Keep Consulting,

More information

Designing Fiber Optic / Ethernet Networks for Industrial and Emergency Applications

Designing Fiber Optic / Ethernet Networks for Industrial and Emergency Applications White Paper: Designing Fiber Optic / Ethernet Networks for Industrial and Emergency Applications Learn more about our Innovations at www.norphonic.com DISCLAIMER This publication is a guide for reference

More information

Application Note. Using PESQ to Test a VoIP Network. Prepared by: Psytechnics Limited. 23 Museum Street Ipswich, Suffolk United Kingdom IP1 1HN

Application Note. Using PESQ to Test a VoIP Network. Prepared by: Psytechnics Limited. 23 Museum Street Ipswich, Suffolk United Kingdom IP1 1HN Using PESQ to Test a VoIP Network Application Note Prepared by: Psytechnics Limited 23 Museum Street Ipswich, Suffolk United Kingdom IP1 1HN t: +44 (0) 1473 261 800 f: +44 (0) 1473 261 880 e: info@psytechnics.com

More information

Agilent Technologies Performing Pre-VoIP Network Assessments. Application Note 1402

Agilent Technologies Performing Pre-VoIP Network Assessments. Application Note 1402 Agilent Technologies Performing Pre-VoIP Network Assessments Application Note 1402 Issues with VoIP Network Performance Voice is more than just an IP network application. It is a fundamental business and

More information

Quality parameters and standards for Telecommunications and Broadcasting networks (Study of Specifications and Recommendations)

Quality parameters and standards for Telecommunications and Broadcasting networks (Study of Specifications and Recommendations) Quality parameters and standards for Telecommunications and Broadcasting networks (Study of Specifications and Recommendations) Executive summary This document is the study report for the Quality parameters

More information

Measuring VoIP QoS. Going Beyond Can You Hear Me Now? Kaynam Hedayat. MPLScon May 2005

Measuring VoIP QoS. Going Beyond Can You Hear Me Now? Kaynam Hedayat. MPLScon May 2005 Measuring VoIP QoS Going Beyond Can You Hear Me Now? Kaynam Hedayat MPLScon May 2005 Overview Why Real-Time VoIP Quality Assurance Matters? Challenges - Going Beyond Can You Hear Me Now? Monitoring Technologies

More information

VoIP / SIP Planning and Disclosure

VoIP / SIP Planning and Disclosure VoIP / SIP Planning and Disclosure Voice over internet protocol (VoIP) and session initiation protocol (SIP) technologies are the telecommunication industry s leading commodity due to its cost savings

More information

Assessing the quality of VoIP transmission affected by playout buffer scheme and encoding scheme

Assessing the quality of VoIP transmission affected by playout buffer scheme and encoding scheme Assessing the quality of VoIP transmission affected by playout buffer scheme and encoding scheme Miroslaw Narbutt, Mark Davis Communications Network Research Institute Dublin Institute of Technology Wireless

More information

A Quality of Experience based Approach for Wireless Mesh Networks*

A Quality of Experience based Approach for Wireless Mesh Networks* A Quality of Experience based Approach for Wireless Mesh Networks* Anderson Morais, and Ana Cavalli Télécom SudParis, France {anderson.morais, ana.cavalli}@it-sudparis.eu Abstract. Wireless Mesh Network

More information

User's Guide bintec R1200 / R1200w(u) / R3000 / R3000w / R3400 / R3800(wu) VoIP

User's Guide bintec R1200 / R1200w(u) / R3000 / R3000w / R3400 / R3800(wu) VoIP User's Guide bintec R1200 / R1200w(u) / R3000 / R3000w / R3400 / R3800(wu) VoIP Copyright December 14, 2006 Funkwerk Enterprise Communications GmbH Version 0.9 Purpose Liability Trademarks Copyright Guidelines

More information

Performance Evaluation of VoIP Services using Different CODECs over a UMTS Network

Performance Evaluation of VoIP Services using Different CODECs over a UMTS Network Performance Evaluation of VoIP Services using Different CODECs over a UMTS Network Jianguo Cao School of Electrical and Computer Engineering RMIT University Melbourne, VIC 3000 Australia Email: j.cao@student.rmit.edu.au

More information

TEMPORARY DOCUMENT. IPTV Performance Monitoring and Reporting

TEMPORARY DOCUMENT. IPTV Performance Monitoring and Reporting INTERNATIONAL TELECOMMUNICATION UNION STUDY GROUP 12 TELECOMMUNICATION STANDARDIZATION SECTOR STUDY PERIOD 2009-2012 TD 140rev1 (GEN/12) English only Original: English Question(s): 13/12 Geneva, 3-12 November

More information

PARAMETRIC SIMULATION OF IMPAIRMENTS CAUSED BY TELEPHONE AND VOICE OVER IP NETWORK TRANSMISSION

PARAMETRIC SIMULATION OF IMPAIRMENTS CAUSED BY TELEPHONE AND VOICE OVER IP NETWORK TRANSMISSION PARAMETRIC SIMULATION OF IMPAIRMENTS CAUSED BY TELEPHONE AND VOICE OVER IP NETWORK TRANSMISSION PACS REFERENCE: 43.72 KB Rehmann, Sebastian; Raake, Alexander; Möller, Sebastian Institute of Communication

More information

WHITE PAPER. IP Telephony Ensuring your Structured Cabling is Suitable

WHITE PAPER. IP Telephony Ensuring your Structured Cabling is Suitable WHITE PAPER IP Telephony Ensuring your Structured Cabling is Suitable Ensuring your Structured Cabling is suitable for IP Telephony Discussions on the impact that a network's structured cabling system

More information

INFORMATION DOCUMENT DRIVE TEST METHODOLOGY FOR QUALITY OF SERVICE MEASUREMENTS

INFORMATION DOCUMENT DRIVE TEST METHODOLOGY FOR QUALITY OF SERVICE MEASUREMENTS INFORMATION DOCUMENT DRIVE TEST METHODOLOGY FOR QUALITY OF SERVICE MEASUREMENTS CONSULTATION PROCESS Background The Uganda Communications Commission is in the process of reviewing the QoS standards for

More information

Unified Communications Group. Designing for Adoption: Real-time Audio in the Real World

Unified Communications Group. Designing for Adoption: Real-time Audio in the Real World Unified Communications Group Designing for Adoption: Real-time Audio in the Real World Information in this document, including URL and other Internet Web site references, is subject to change without notice.

More information

920-803 - technology standards and protocol for ip telephony solutions

920-803 - technology standards and protocol for ip telephony solutions 920-803 - technology standards and protocol for ip telephony solutions 1. Which CODEC delivers the greatest compression? A. B. 711 C. D. 723.1 E. F. 726 G. H. 729 I. J. 729A Answer: C 2. To achieve the

More information

Network performance objectives for IP-based services Amendment 1: New Appendix XII Considerations for low speed access networks

Network performance objectives for IP-based services Amendment 1: New Appendix XII Considerations for low speed access networks International Telecommunication Union ITU-T Y.1541 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 (12/2013) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION

More information

Quality of Service Testing in the VoIP Environment

Quality of Service Testing in the VoIP Environment Whitepaper Quality of Service Testing in the VoIP Environment Carrying voice traffic over the Internet rather than the traditional public telephone network has revolutionized communications. Initially,

More information

Level 1 Technical. Networking and Technology Basics. Contents

Level 1 Technical. Networking and Technology Basics. Contents Level 1 Technical Networking and Technology Basics Contents 1 Glossary... 2 2 IP Networking Basics... 4 Fundamentals... 4 IP Addresses... 4 Subnet Masks... 5 Network Communication... 6 Transport Protocols...

More information

Achieving PSTN Voice Quality in VoIP

Achieving PSTN Voice Quality in VoIP Achieving PSTN Voice Quality in VoIP Voice over Internet Protocol (VoIP) is being widely deployed to offer users low-cost alternatives for long-distance and international telephone calls. However, for

More information

QoS Mapping of VoIP Communication using Self-Organizing Neural Network

QoS Mapping of VoIP Communication using Self-Organizing Neural Network QoS Mapping of VoIP Communication using Self-Organizing Neural Network Masao MASUGI NTT Network Service System Laboratories, NTT Corporation -9- Midori-cho, Musashino-shi, Tokyo 80-88, Japan E-mail: masugi.masao@lab.ntt.co.jp

More information

Version 0.1 June 2010. Xerox WorkCentre 7120 Fax over Internet Protocol (FoIP)

Version 0.1 June 2010. Xerox WorkCentre 7120 Fax over Internet Protocol (FoIP) Version 0.1 June 2010 Xerox WorkCentre 7120 Fax over Internet Protocol (FoIP) Thank you for choosing the Xerox WorkCentre 7120. Table of Contents Introduction.........................................

More information

B12 Troubleshooting & Analyzing VoIP

B12 Troubleshooting & Analyzing VoIP B12 Troubleshooting & Analyzing VoIP Phillip Sherlock Shade, Senior Forensics / Network Engineer Merlion s Keep Consulting phill.shade@gmail.com Phillip Sherlock Shade (Phill) phill.shade@gmail.com Phillip

More information

Assessment of VoIP quality across ADSL downlinks

Assessment of VoIP quality across ADSL downlinks Assessment of VoIP quality across ADSL downlinks Technische Universität Dresden Chair of Telecommunications Qin Dai 16.11.06 Contents 2 Introduction and motivation VoIP quality vs. ADSL downlinks VoIP

More information

New Models for Perceived Voice Quality Prediction and their Applications in Playout Buffer Optimization for VoIP Networks

New Models for Perceived Voice Quality Prediction and their Applications in Playout Buffer Optimization for VoIP Networks New Models for Perceived Voice Quality Prediction and their Applications in Playout Buffer Optimization for VoIP Networks Dr. Lingfen Sun Prof Emmanuel Ifeachor University of Plymouth United Kingdom {L.Sun;

More information

Performance Analysis of the Opus Codec in VoIP Environment Using QoE Evaluation

Performance Analysis of the Opus Codec in VoIP Environment Using QoE Evaluation Performance Analysis of the Opus Codec in VoIP Environment Using QoE Evaluation Péter Orosz, Tamás Skopkó, Zoltán Nagy, and Tamás Lukovics Faculty of Informatics University of Debrecen Debrecen, Hungary

More information

SIP Trunking and Voice over IP

SIP Trunking and Voice over IP SIP Trunking and Voice over IP Agenda What is SIP Trunking? SIP Signaling How is Voice encoded and transported? What are the Voice over IP Impairments? How is Voice Quality measured? VoIP Technology Confidential

More information

Voice over IP Probe! for Network Operators and! Internet Service Providers

Voice over IP Probe! for Network Operators and! Internet Service Providers Voice over IP Probe! for Network Operators and! Internet Service Providers Product Presentation September 2011 2011 ADVENAGE GmbH Agenda Voice over IP Probe Key Facts VoIP Probe in a Nutshell Use Cases

More information

Analysis and Simulation of VoIP LAN vs. WAN WLAN vs. WWAN

Analysis and Simulation of VoIP LAN vs. WAN WLAN vs. WWAN ENSC 427 Communication Networks Final Project Report Spring 2014 Analysis and Simulation of VoIP Team #: 2 Kadkhodayan Anita (akadkhod@sfu.ca, 301129632) Majdi Yalda (ymajdi@sfu.ca, 301137361) Namvar Darya

More information

PETER CUTLER SCOTT PAGE. November 15, 2011

PETER CUTLER SCOTT PAGE. November 15, 2011 Future of Fax: SIP Trunking PETER CUTLER SCOTT PAGE November 15, 2011 QUESTIONS AND ANSWERS TODAY S SPEAKERS Peter Cutler Vice President of Sales Instant InfoSystems Scott Page Subject Matter Expert Dialogic

More information

INTERNATIONAL TELECOMMUNICATION UNION. SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK Interworking with other networks

INTERNATIONAL TELECOMMUNICATION UNION. SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK Interworking with other networks INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU V.150.0 (01/2003) SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK Interworking with other networks Modem

More information

Accuracy Analysis on Call Quality Assessments in Voice over IP

Accuracy Analysis on Call Quality Assessments in Voice over IP Accuracy Analysis on Call Quality Assessments in Voice over IP Yi Han, John Fitzpatrick, Liam Murphy, Jonathan Dunne School of Computer Science and Informatics University College Dublin Email: yi.han@ucdconnect.ie,

More information

R&S IP-GATE IP gateway for ISDN encryption devices

R&S IP-GATE IP gateway for ISDN encryption devices Secure Communications Product Brochure 0.00 R&S IP-GATE IP gateway for ISDN encryption devices R&S IP-GATE At a glance The R&S IP-GATE is an IP interface for the most recent models of the R&S MKS9680 and

More information

MULTI-STREAM VOICE OVER IP USING PACKET PATH DIVERSITY

MULTI-STREAM VOICE OVER IP USING PACKET PATH DIVERSITY MULTI-STREAM VOICE OVER IP USING PACKET PATH DIVERSITY Yi J. Liang, Eckehard G. Steinbach, and Bernd Girod Information Systems Laboratory, Department of Electrical Engineering Stanford University, Stanford,

More information

THE ANALYSIS AND SIMULATION OF VOIP

THE ANALYSIS AND SIMULATION OF VOIP ENSC 427 Communication Networks Spring 2013 Final Project Presentation THE ANALYSIS AND SIMULATION OF VOIP Presented by Team #3: Demet Dilekci Conrad Wang Jiang Feng Xu ddilekci@sfu.ca cjw11@sfu.ca jfxu@sfu.ca

More information

Combining Voice over IP with Policy-Based Quality of Service

Combining Voice over IP with Policy-Based Quality of Service TechBrief Extreme Networks Introduction Combining Voice over IP with Policy-Based Quality of Service Businesses have traditionally maintained separate voice and data networks. A key reason for this is

More information

ANALYSIS OF LONG DISTANCE 3-WAY CONFERENCE CALLING WITH VOIP

ANALYSIS OF LONG DISTANCE 3-WAY CONFERENCE CALLING WITH VOIP ENSC 427: Communication Networks ANALYSIS OF LONG DISTANCE 3-WAY CONFERENCE CALLING WITH VOIP Spring 2010 Final Project Group #6: Gurpal Singh Sandhu Sasan Naderi Claret Ramos (gss7@sfu.ca) (sna14@sfu.ca)

More information

Quality of Service (QoS) and Quality of Experience (QoE) VoiceCon Fall 2008

Quality of Service (QoS) and Quality of Experience (QoE) VoiceCon Fall 2008 Quality of Service (QoS) and Quality of Experience (QoE) VoiceCon Fall 2008 John Bartlett NetForecast, Inc. john@netforecast.com www.netforecast.com VoIP Deployment Realities VoIP is not just another application

More information

Introduction to Packet Voice Technologies and VoIP

Introduction to Packet Voice Technologies and VoIP Introduction to Packet Voice Technologies and VoIP Cisco Networking Academy Program Halmstad University Olga Torstensson 035-167575 olga.torstensson@ide.hh.se IP Telephony 1 Traditional Telephony 2 Basic

More information

WAN Data Link Protocols

WAN Data Link Protocols WAN Data Link Protocols In addition to Physical layer devices, WANs require Data Link layer protocols to establish the link across the communication line from the sending to the receiving device. 1 Data

More information

KPIs for Mobile Services

KPIs for Mobile Services KPIs for Mobile Services MTSI - Multimedia Telephony Services over IMS Effects of Transmission Performance on Multimedia QoS STQ Mobile represented by K. Adler, J. Gustafsson, G. Heikkilä ETSI 2007. All

More information

VoIP Provisioning Test Solutions

VoIP Provisioning Test Solutions VoIP Provisioning Test Solutions Active Service Assurance The World s Smallest VoIP Service Quality Tester Start tests and view results using Tektronix s PocketDQ Software. Compatible with any web-enabled

More information

Voice over IP. Overview. What is VoIP and how it works. Reduction of voice quality. Quality of Service for VoIP

Voice over IP. Overview. What is VoIP and how it works. Reduction of voice quality. Quality of Service for VoIP Voice over IP Andreas Mettis University of Cyprus November 23, 2004 Overview What is VoIP and how it works. Reduction of voice quality. Quality of Service for VoIP 1 VoIP VoIP (voice over IP - that is,

More information

Performance Evaluation of Different Modulation Coding for Scheduling Services over VoIP in WIMAX Networks

Performance Evaluation of Different Modulation Coding for Scheduling Services over VoIP in WIMAX Networks Performance Evaluation of Different Modulation Coding for Scheduling Services over VoIP in WIMAX Networks Hussein M. Hathal Al- Mustansiriyah University, College of Engineering, Electrical Engineering

More information

Measurement of IP Transport Parameters for IP Telephony

Measurement of IP Transport Parameters for IP Telephony Measurement of IP Transport Parameters for IP Telephony B.V.Ghita, S.M.Furnell, B.M.Lines, E.C.Ifeachor Centre for Communications, Networks and Information Systems, Department of Communication and Electronic

More information

Padma Charan Das Dept. of E.T.C. Berhampur, Odisha, India

Padma Charan Das Dept. of E.T.C. Berhampur, Odisha, India Volume 5, Issue 3, March 2015 ISSN: 2277 128X International Journal of Advanced Research in Computer Science and Software Engineering Research Paper Available online at: www.ijarcsse.com Measuring Quality

More information

NCTU-VT: a freeware for wireless VoIP performance measurement

NCTU-VT: a freeware for wireless VoIP performance measurement WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2012; 12:318 324 Published online 12 May 2010 in Wiley Online Library (wileyonlinelibrary.com)..963 RESEARCH ARTICLE NCTU-VT: a

More information

Voice over IP Basics for IT Technicians

Voice over IP Basics for IT Technicians Voice over IP Basics for IT Technicians White Paper Executive summary The IP phone is coming or has arrived on desk near you. The IP phone is not a PC, but does have a number of hardware and software elements

More information

Troubleshooting Voice Over IP with WireShark

Troubleshooting Voice Over IP with WireShark Hands-On Course Description Voice over IP is being widely implemented both within companies and across the Internet. The key problems with IP voice services are maintaining the quality of the voice service

More information

UNDERSTANDING SIP TRUNKING

UNDERSTANDING SIP TRUNKING UNDERSTANDING SIP TRUNKING CHAPTER ONE: THE ORIGINS OF SIP The Internet as we know it began as ARPANET (a.k.a. the Advanced Research Projects Agency Network) in 1969. ARPANET started out as a four-node

More information

Voice Over IP Performance Assurance

Voice Over IP Performance Assurance Voice Over IP Performance Assurance Transforming the WAN into a voice-friendly using Exinda WAN OP 2.0 Integrated Performance Assurance Platform Document version 2.0 Voice over IP Performance Assurance

More information

Analog-to-Digital Voice Encoding

Analog-to-Digital Voice Encoding Analog-to-Digital Voice Encoding Basic Voice Encoding: Converting Analog to Digital This topic describes the process of converting analog signals to digital signals. Digitizing Analog Signals 1. Sample

More information

A realisitic VoIP traffic generation and evaluation tool for OMNeT++

A realisitic VoIP traffic generation and evaluation tool for OMNeT++ A realisitic VoIP traffic generation and evaluation tool for OMNeT++ Mathias Bohge Telecommunication Networks Group, TU Berlin Einsteinufer 25, 1587 Berlin, Germany bohge@tkn.tu-berlin.de Martin Renwanz

More information

A New Adaptive Redundancy Control Algorithm For VoIP Applications

A New Adaptive Redundancy Control Algorithm For VoIP Applications A New Adaptive Redundancy Control Algorithm For VoIP Applications Haytham Assem, David Malone Hamilton Institute, National University of Ireland Maynooth, Ireland Email: {Hitham.Salama.2012, David.Malone}@nuim.ie

More information

1. Introduction. VOIP, Version 1.6e T.O.P. BusinessInteractive GmbH Page 1 of 11

1. Introduction. VOIP, Version 1.6e T.O.P. BusinessInteractive GmbH Page 1 of 11 1. Introduction VOIP, Version 1.6e T.O.P. BusinessInteractive GmbH Page 1 of 11 1.1 Telephone and Data Networks...3 1.2 The classic Telecommunication System and Connections...4 1.3 The Voice over IP Concept

More information

Perceived Speech Quality Prediction for Voice over IP-based Networks

Perceived Speech Quality Prediction for Voice over IP-based Networks Perceived Speech Quality Prediction for Voice over IP-based Networks Lingfen Sun and Emmanuel C. Ifeachor Department of Communication and Electronic Engineering, University of Plymouth, Plymouth PL 8AA,

More information

VoIP in 802.11. Mika Nupponen. S-72.333 Postgraduate Course in Radio Communications 06/04/2004 1

VoIP in 802.11. Mika Nupponen. S-72.333 Postgraduate Course in Radio Communications 06/04/2004 1 VoIP in 802.11 Mika Nupponen S-72.333 Postgraduate Course in Radio Communications 06/04/2004 1 Contents Introduction VoIP & WLAN Admission Control for VoIP Traffic in WLAN Voice services in IEEE 802.11

More information

Implementation of Voice over IP and Audio over IP in the Studio environment

Implementation of Voice over IP and Audio over IP in the Studio environment Mediatech 2015 Implementation of Voice over IP and Audio over IP in the Studio environment Wilfried Hecht, Managing Director AVT Audio Video Technologies GmbH Nordostpark 12 90411 Nuernberg Germany Email:

More information

VOICE over IP H.323 Advanced Computer Network SS2005 Presenter : Vu Thi Anh Nguyet

VOICE over IP H.323 Advanced Computer Network SS2005 Presenter : Vu Thi Anh Nguyet VOICE over IP H.323 Advanced Computer Network SS2005 Presenter : Vu Thi Anh Nguyet 1 Outlines 1. Introduction 2. QoS in VoIP 3. H323 4. Signalling in VoIP 5. Conclusions 2 1. Introduction to VoIP Voice

More information

VoIP 101. E911-Enhanced 911- Used for providing emergency service on cellular and internet voice calls.

VoIP 101. E911-Enhanced 911- Used for providing emergency service on cellular and internet voice calls. If you ve been researching phone systems for awhile, you ve probably heard the term VoIP. What s the definition? Do you need certain hardware for it to work? There are a few questions that should be answered

More information

VOICE OVER IP AND NETWORK CONVERGENCE

VOICE OVER IP AND NETWORK CONVERGENCE POZNAN UNIVE RSITY OF TE CHNOLOGY ACADE MIC JOURNALS No 80 Electrical Engineering 2014 Assaid O. SHAROUN* VOICE OVER IP AND NETWORK CONVERGENCE As the IP network was primarily designed to carry data, it

More information