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Purchasing a router may sound like a pretty simple task. This however can become somewhat challenging when VOIP comes into play.
There a couple of core functions that your choice of router …

Skills Covered by this Module

General Internet Connectivity concepts.
Using the Firewall Checker as a first check to identify Firewall Configuration errors or warnings.
Firewall Configuration – Port Forwarding.
Firewall Configuration – Quality of Service (QoS).

Relevant Course Materials

A …

Downgrading or Upgrading the firmware of a Grandstream GXW-4104, GXW-4108 gateway for use with 3CX Phone System for Windows

TFTP stands for Trivial File Transfer Protocol simply because of its simplicity.  It is mainly used for automated file transfers between machines on UDP Port 69.  In a VoIP environment TFTP is used to upload …

Many users are battling with Sonicwall devices, and even though 3CX cannot provide support for this, we have the following notes to hopefully help you with your configuration.

Correct Router Configuration is a key element in ensuring correct communications between 3CX PhoneSystem and external entities such as external extensions, VoIP Provider services, and other Bridged PBXs.
NAT and/or PAT
When a network host A sends …

If you have been asking yourself how to secure 3CX PhoneSystem, read on…

In this article we will describe the configuration of a hardware router with a very attractive quality-price ratio. The Draytek 2820 is a ADSL 2/2+ Router/Firewall with advanced features such as the capability to establish …

This document will provide an overview of the more common concepts which need to be kept in mind when configuring 3CX PhoneSystem inside your network infrastructure, including the following topics:

NAT Configuration
STUN Resolution
DNS Resolution in a …

In order for 3CX Phone System to communicate successfully with VoIP providers and Remote Extensions, your firewall/router device must be configured for SIP operation. To maximize your chances of success, make sure you choose a …

Click to download the stand-alone SIP Proxy Manager
What is the 3CX SIP Proxy manager
The SIP Proxy Tunnel can combine all SIP (signaling) and RTP (media) VoIP Packets from one location (typically a remote office) …