What is Telephone Number System (TNS)?

intelli-CTi – Telephone Number System (TNS) What is it and why?

This article considers some of the data management hurdles faced when implementing Computer Telephony Integration (CTI), and why we implemented Telephone Number System (TNS) in our integrations.

CTI - What is Telephone Number System (TNS)

There are several scenarios to consider:

  1. Managing the numbers such that inbound calls can be matched to records within the application accurately and quickly
  2. Managing the numbers so that outbound calls can be dialled from the application successfully, including internationally
  3. Ensuring the format within the system is compatible with other system components. Here I am thinking about where data is perhaps synced to Outlook/mobile applications so user can dial out from those

In our experience most applications do little to assist the integrator. Dynamics 365 for example does nothing to manage the format of the data captured, it is a pure free form text field, you could apply a mask, but this would only cover a single country format.

Some systems may have separate fields for Country Code, Area Code etc, but that is not common.

So you need a capability within your integration to be able to deal with all manner of phone number entry examples:

  • 01329 222800
  • +44 1329 222800 ext 101
  • 0044 (0) 1329 222800 – 101
  • 44132922 2800 ext 101

You get the idea. These are just some of the ways a number may be entered, as human beings we can decipher this and make a reasonable guess as to what to dial, but as we know systems need a little more structure and uniformity to work effectively.

Our integration with Dynamics 365 includes TNS, which is a phone number data management sub system. This handles the task of applying a uniform structure to the data, which for inbound calls means that unless an entry is very poor in format or incomplete, we can return a very high hit rate. It also includes some other neat tricks such that the look up performance is fast! This combination provides a great user experience, a quick and accurate record lookup.

For outbound calls, you are reliant on the data held being complete, even if the format is somewhat inconsistent. At least then with a good knowledge of the various country code and area code dialling rules you stand a reasonable chance of building the outbound part of the integration to achieve a successful call.

So if you are considering building telephony integration, you need to consider the issue of managing phone numbers. Clearly the more you are able to do in the data capture process to enforce a standard the better. In our Infor CRM (Saleslogix) integration, we re-wrote the Account/Contact data capture process completely and included in that the explicit capture of the appropriate country code and segmentation of the area code and number. This was a LOT of work, you may not have that luxury or budget!

Without the ability to enforce the systematic phone number data capture, you have to rely on user training. We have found that the key incentive for the user to follow a standard format was the usability of the data on mobiles as a result.

We use what is known as the canonical format: +44 (01329) 222800

However, even with good training and the users doing the right thing, you still need to allow for other methods of data capture, like web captured leads etc that may not be so correct.

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See the intelli-CTi Help Center User Guidelines for important considerations of use.