Is your LAN ready for VoIP telephony?
Setting up your dmSwitchboard12 to use VoIP (Voice over IP) technology is a great way to save on call costs.
VoIP can provide an excellent service, but to use VoIP you need a good quality internet connection or your call quality will be compromised.
This Note gives guidelines for the LAN quality you will need in order to run a reliable dmSwitchboard12 using VoIP.
Shared ADSL
If you have a shared ADSL connection, because you're using your ADSL line for other purposes besides running your dmSwitchboard12, you need:
- An upstream connection speed of 200KB/sec (Kilobytes per second) for a connection, and
- 125KB/sec for each additional Personal Extension
You should contact your ADSL provider to check your expected connection speed.
Additionally, you can use one of the many online speed checkers, such as www.speedtest.net, to gauge the actual upload/download speeds for your connection.
Dedicated ADSL
If you have a dedicated ADSL connection, that is you have a separate ADSL line solely for running your dmSwitchboard12, then you need an upstream connection of 120kbps for each Personal Extension.
State of LAN
We recommend that you use:
- VoIP phones with static IP addresses
- A separate ADSL or subnet for to connect the VoIP phones
Hardware
The quality of your VoIP network is heavily dependent on the quality of the hardware that you use.
The standard routers and hubs supplied by ISPs to private customers are not robust enough to be used in a commercial setting. If you will be having more than three users on your system we recommend that you purchase commercial-grade hardware to support them. The cost of this equipment will be easily repaid by its reliability and resilience.
Contacting Support
You need to be aware that setting up a VoIP service is not always straightforward. You may face a number of technical challenges before your system operates smoothly. These will vary depending on your LAN topography, user requirements, hardware and software.
Although Support are able to offer advice and guidance on checking your LAN prior to using VoIP, this is not a free service.
Please contact support, buy phone or email, if you would like to discuss how they can help you.
VoIP Handsets
We have created a number of dmNotes to help you install and test VoIP phones (you can search for them under the handset's name).
Please be aware, however, that these handsets are neither supported nor supplied by dmClub. Please do not contact dmClub Support if you have any difficulties installing or operating them.
In this case, please contact the handset's vendor or the manufacturer.
Related content
You may find the following links useful:
http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
dmNote 3511 - Getting started with VoIP (includes SIP Server configuration details)