Ask the Expert

Hardware and bandwidth requirements for VoIP

My company is asking me to supply them with 5 VoIP telephones. I have never dealt with setting up VoIP phones before. I want to be sure that I purchase the right equipment. First, what type of router, switches and hardware do I need to get VoIP working? Second, what type of bandwidth does VoIP require? I am working with 1 Mbps up and down. Is that enough,not enough or too much?

    Requires Free Membership to View

There are a number of questions to be asked and understood here. For example:

- Is it planned that the VoIP phones operate in a stand alone manner (e.g. dialing each other by IP address)

- Are these VoIP phones for remote workers?

- Do you need these VoIP phones to be reachable from an existing phone system (PBX)?

If the VoIP phones you select are based on open standards, your existing network infrastructure may be sufficient.

Each VoIP call using compressed voice (G.729) requires about 24 Kbps upstream and downstream. If this 1Mb/s connection is dedicated for this VoIP application, that is sufficient. If this 1Mbps connection is shared as a connection to the Internet some additional equipment may be required to ensure good voice quality.

A good idea would be to contact a reseller of VoIP equipment for help and advice.

http://www.zultys.com/index.jsp?tab=find_a_reseller.

This was first published in October 2005