January 18, 2021
Hot Topics:

Selecting a VoiceXML Gateway

  • By Jonathan Eisenzopf
  • Send Email »
  • More Articles »

As vendors continue to introduce new VoiceXML gateways, the task of selecting the right solution has become more difficult. This article will provide you with a number of selection criteria to help you ask the right questions when evaluating VoiceXML gateway options.


A VoiceXML gateway is the server software that handles interactions between callers on standard analog lines (or VoIP) and voice applications on a Web server. In a way, the fact that a common standard exists for IVR functionality means that VoiceXML gateways could soon become a commodity technology offered by every phone device manufacturer. Until the time when VoiceXML functionality comes standard with your PBX or phone system, you may be stuck with the difficult task of selecting an independent VoiceXML vendor.

Vendor Standardization

If your company has standardized on a particular vendor for networking or telephony gear, your best bet is to contact the vendor to see if they offer a VoiceXML gateway product. If they do, chances are that it will be easier to integrate the vendor's product with your other equipment. Cisco, Lucent, Nortel, and Siemens are all examples of companies who can provide a VoiceXML gateway that integrates with their telephony and/or networking equipment.

Have your requirements in hand

Don't make the mistake of letting the vendor dictate your selection criteria. This happens when you start talking to vendors before you have determined what your needs actually are. It's very easy to fall into the trap of comparing vendors based on a differentiator that one vendor emphasizes when it may not be of any value to your company.

Before you approach the first vendor, make sure you have the following information at hand:

  • Expected call volume - How many calls do you expect per day? How many simultaneous calls do you expect at peak volumes?
  • Legacy system - What equipment will the VoiceXML gateway need to integrate with? Common equipment that you need to be concerned with would be your PBX, ACD, phone system, or IVR system.
  • TTS channels - Will your system require any text-to-speech functionality, or will every prompt be be-recorded?

Deciding Factors: Cost, Support, Ease of Integration, and Development Tools

Once you have narrowed your list of potential vendors, your decision will likely be based on cost, the quality and level of customer support, the level of complexity required to integrate the solution with your existing infrastructure, and the development tools that come with the VoiceXML gateway.

Most vendors use the same underlying hardware and software, so performance, scalability and reliability of all platforms will be comparable with some exceptions. 

One area where vendors differ is in the way they extend the platform to integrate with other systems. For example, one vendor may offer seamless integration with Java application servers, while another focuses on packing high-performance into a single connected platform. Another vendor may focus on integrating with automated outbound call systems or call distributors. Some vendors support Windows, some Unix, some both. Based on your specific integration needs, you should be able to narrow the number of qualified vendors down to 2 or 3.

Another area you should focus on is development tools. Each vendor provides their own unique set of development tools that are tuned to work with their platform. Have one of your developers work with the tool to ensure that it meets your expectations and needs. Because VoiceXML itself is a fairly new technology, not all of the development tools are fully mature, so be careful.

Then ask yourself what you will expect from the vendor in terms of technical support. Are they ready to provide the needed level of support?

Page 1 of 2

This article was originally published on September 28, 2002

Enterprise Development Update

Don't miss an article. Subscribe to our newsletter below.

Thanks for your registration, follow us on our social networks to keep up-to-date