Application Notes

Telchemy is pleased to present the following series of Application Notes for free download. These documents provide a brief introduction to VoIP and IP Video performance management concepts and terminology, and present guidelines for managing media service quality in specific network environments.

IP Video Performance Management

Measuring the Quality of Video Streaming Services Describes commonly used video streaming methods and protocols, and explains how objective measurement tools can be used to monitor and manage viewer QoE. Apr 2015
IP Video Encoding Explained Explains how video is encoded and transmitted over IP, describes common impairments that can affect video perceptual quality, and lists some basic approaches to IP video performance management. Sep 2012
Understanding IP Video Quality Metrics Describes some of the typical issues and problems affecting IPTV service quality, the testing methods used to measure quality, and the primary video quality metrics and what they represent. Sep 2012
TVQM Video Quality Metrics Describes some of the typical issues and problems affecting IP Video service quality and describes Telchemy's Video Quality Metrics (TVQM), which provide key insights into video service performance. Sep 2012
Managing IPTV Performance Describes some of the typical issues and problems affecting IPTV service quality, and introduces a cost-effective approach to service quality monitoring. Sep 2012


Voice over IP Performance Management

Managing Enterprise IP Telephony Describes typical issues that network managers encounter when deploying Enterprise IP Telephony and introduces the standards-based management framework that allows them to detect, address, and resolve these problems. Apr 2017
Voice Quality Measurement Describes commonly used call quality measurement methods, explains the metrics in practical terms and describes acceptable voice quality levels for Voice over IP services. Nov 2014
Impact of Delay on VoIP Services Describes the sources of delay in Voice over IP services, the impact of this delay on conversational quality and, how to define acceptable levels of delay in service level definitions or agreements. Jan 2006
Impact of Echo on VoIP Services Describes why echo occurs, what effects it has on voice quality, how echo cancellation and suppression work and how to troubleshoot echo problems. Jan 2006
Data and Fax Modem Performance on VoIP Services Describes the typical performance issues that users and designers of both data modems of all types, and Analog Telephone Adaptors (ATAs) face when using Voice over IP (VoIP). Jul 2006
Voice Quality Estimation in Wireless & TDM Environments Describes the impact of noise, signal level, echo, frame erasure and other common problems on voice quality in digital cellular and TDM environments. Apr 2006
Managing IP Centrex & Hosted PBX Services Describes typical performance issues that service providers encounter when deploying Hosted PBX / IP Centrex networks and introduces a management framework that enables them to detect, address and resolve these problems. May 2004
Managing Wireless LANs and Wi-Fi Services Describes typical performance issues that enterprises and service providers encounter when deploying VoIP over wireless LANs (VoWLANs) and Wi-Fi services and introduces a management framework that enables them to detect, address and resolve these problems. Jan 2005
Six Steps to Getting Your Network Ready for Voice over IP Provides enterprise network managers with a six step methodology, including pre-deployment testing and network readiness assessment, to follow when preparing their network for Voice over IP service. Jan 2005
Managing Cable Telephony Services Describes typical performance issues that cable operators encounter when deploying cable telephony networks and introduces a management framework that enables them to detect, address and resolve these problems. Jun 2004