The abbreviation DTMF stands for Dual Tone Multiple-Frequency, also called Touch Tone. This can be a code that is used to send information with radio och phone. The prestigious American company Bell Labs that is owned by Nokia is the developer of DTMF.

The tones you hear when pressing buttons on a phone, it DTMF. Every click sends two tones on two different frequencies.Every number have their own, predestined frequencies. Number 1 consists of the tones 697 and 1209 Hz for example. The system has also proved reliability.

DTMF came to the US in the 1940s as a streamline of a system for telephony that then was built on the impulse system, with a rotary dial. Many that grew up in the 1970s or earlier are used to phones with rotary dials which were much more ineffective to call with.

  • DTMF is a way to send information over vast distances
  • The US based company Bell Labs invented the technique
  • DTMF technique isn’t interruption sensitive and is considered reliable
  • DTMF is a standard in phone telephony companies
  • The previous system was phones with rotary dials
  • Every number is coded with 2 tones on predestined frequencies
  • Number recognition technique is excepted to be the next big breakthrough in the field

Bell Labs – The pioneer in telecommunication

Similarly to how long we’ve had access to the telegraph and telephony in whole, we’ve needed ways to interact with systems in a mechanical way. Signaling systems have been developed to fill that need – both in regard to routing and calling, as well as integrating with a telephony system.

The first versions of phone signalling were pulse calls. Rotating phones interrupted electric connections when they turned, which resulted in electric pulses that were produced and were read as commandos. The first DTMF sound producing phones were introduces by Bell Systems. This version was far more easy to use and worked noticeably faster.

Bell Labs is an American research company in telecommunication and is owned by Nokia, hence the new name “Nokia Bell Labs”. The company was founded in 1925 and is associated with the progress in information technology and telecommunication.

DTMF set a completely new standard in telephony and was a huge breakthrough. The Touch Tone phones became a necessity in industrially developed countries. The earlier system didn’t have tones, the numbers instead corresponded a number of pulses and took longer to dial.

DTMF is just one of many Bell Lab’s inventions. This research company has also contributed with important progress in sun-cell technology, transistor technology and program language. They also invented the operating system Unix and the first 32-bit micro processor (BELLMAC-32A). It’s interesting to see that the successful company now remains in nordic possession through Nokia.

DTMF masking

In many organisations, the contact center is a vital organ of their service operation. And this can also suffice as a bigger hub for transaktions. Because of this it’s important to find a solution that is safe and effective, and one of these solutions is DTM masking. Instead of reading out numerical numbers to a service representative, you click buttons on your keypad and every click generates a corresponding signal that is sent through the phone line. Before it reaches the contact center it’s picked up by a unit that converts it to data packets, and then transfers it further to the final destination. This allows companies to handle sensitive data without it directly being managed by someone in the contact center, and it’s also a substitute for functions like record or pause.

DTMF supression can be used to manage card payments over the phone. And instead of customers reading out their card numbers out loud, they can easily share the numbers by clicking the corresponding buttons on the phone. During the process, the clicks are picked upp in data and the agent will neither see nor hear the numbers. Instead they only hear tones that correspond to zeros or ones that represent masked numbers on the screen in real time. When the customer has clicked all the numbers needed, and the system has verified that the information is correct, the transaction will be transferred to the payment service. During this time no sensitive data is actually managed directly and it also isn’t stored anywhere. And most importantly, the agent can communicate at the same time and help them troubleshoot if needed.

The DTMF masking benefits

DTMF masking is first of all a really easy way to make sure that you’re PCI DSS compliant, and secondly; it comes with a row of useful benefits. The solution has been implemented in many companies and is one of the few solutions that allow you to manage sensitive data in a safe way while still being able to maintain the same level of service.

  1. Better customer service – Since the agent can stay on the phone the entire time of the process, no calls need to be transferred. This allows the agent to talk while the transaction is being processed and alleviates if any errors should occur.
  2. Less management time – The solution makes it easy for the customer with just having to click their numbers once, and this also decreases the possibility of errors during the transaction. The information also doesn’t have to be reproduced or corrected by CSR , which also means that a representative doesn’t have to read or confirm any information from the customer. The CSR can therefore be free to conclude all the activities instead.
  3. Better CSR–  To not have a CSR representative exposed to sensitive data form the customer removes the need to have strict PCI DSS controls. CSR may access the tools needed to do their job but don’t have to go through any extensive security measures.
  4. Less exploitation risk – Since the card information isn’t stored or managed directly in the contact center and its infrastructure, hackers can’t access any information

The future of DTMF

The Touch Tone function is something you need to activate in modern mobile phones and you can in general call without it. In december 2010, most companies began replacing DTMF with voice recognition, and it’s safe to assume that in the long run it will be completely replaced by new systems.

Before there was a close connection between DTMF and radio, but even radio is merging over to web-based solutions that don’t require Touch Tone. However, it’s important to note that DTMF is a system that has been in use for a long time despite of how fast new technique is developed today.

Voice recognition is built on the fundamental idea that phones and computers learn to understand human language. Instead of sending tones we just have to say the numbers out loud instead. However, Touch Tone  isn’t completely out of the game quite yet, it will be around for a while.

Last update 10/12-19