Century IT blog

VoIP Jitter & Packet Loss

November 29th, 2010



One of the biggest design and installation mistakes we come across in many other 3CX VoIP installations is perhaps the intended sharing of a single business broadband connection with 3CX VoIP trunks and all of the other business internet activities e.g. Surfing, downloads, email, mobile and remote access etc.


Trying to ‘stuff’ everything down a single broadband connection is not a good idea, on a busy or saturated broadband connection, the first service to experience problems will typically be the VoIP Siptrunk Traffic, callers will begin to experience ‘Jitter’ (delays in the voice conversation by each party) and ‘packet loss’ (conversation drops out – parts of the conversation are not heard).


Most modern business broadband routers support a feature called QOS (Quality of Service) whereby VoIP traffic can be prioritised by the router. Basically what happens is that VoIP traffic is prioritised over other types of internet traffic i.e. Surfing & Email, basically internet traffic which does not require ‘real time’ communication over the broadband connection.


3cx voip telephone systems

This QOS feature does help ‘share’ a broadband connection relatively succesfully but in our experience there are times again when upon broadband saturation VoIP traffic will begin to suffer Jitter and Pack Loss.


If you are suffering from Jitter and Packet Loss the other consideration is your Internet Service Provider, would your ISP know if they have a system where they prioritise VoIP Traffic over their network and the Internet? If they don’t then it doesn’t really matter that you have the right equipment and configuration, VoIP traffic problems will occur further upstream.




What do we recommend?


  • We would advise against sharing a broadband connection, 3CX Sip traffic with other computer network systems & services


  • We would recommend you select an Internet Service Provider (ISP) who specialise in VoIP and can offer a prioritised VoIP traffic service


  • Look at what VoIP Codec you are using and perform a mathematical calculation against your available bandwidth


  • Why not use a 3CX recommended VoIP SIp Trunk provider who have a dedicated VoIP Service


  • Speak to us about a dedicated VoIP gateway to interface your existing BT phone lines, we have solutions for PSTN, ISDN2e, ISDN30 and mobile/gsm networks



3cx voip telephone systems



If you think you are suffering from a broadband / VoIP traffic capacity or bottleneck problem, in the first instance try this VoIP Tester


VoIP Tester – VoIP Tester

Why not give us a call to discuss how we can expertly support your 3CX VoIP Telephone System investment or make productivity improvement recommendations?



Century IT Services – Providing expert 3CX VoIP Telephone Installations & Support in Hampshire, Dorset, Wiltshire, Surrey, Sussex, & Berkshire.