Caller ID: the difference between DTMF and FSK
DTMF vs FSK
There are 2 types of caller ID. For landline phones, you'll have DTMF, and via cable, you'll have FSK. DTMF is only supported in the Netherlands, and FSK is both in the Netherlands and Belgium. In addition, DTMF only works with KPN, while FSK works with all other providers. Almost all our phone support both DTMF and FSK.
The differences
DTMF providers
DTMF stands for Dual Tone Multi Frequency. KPN is the only provider that uses DTMF for caller ID. If you have a KPN phone plan and you have a landline phone that supports FSK, the caller ID won't work via the KPN network. Do you always want to be sure of caller ID via KPN? Choose a landline phone that supports both DTMF and FSK. Luckily, almost all our phones do so.
FSK providers
FSK stands for Frequency Shift Keying and is used by providers such as Ziggo and Tele2. In Belgium too, mainly FSK is used. Compared to DTMF there are more possibilities at FSK than just number display. This way the name display can also be sent. If in doubt, always contact your provider. ** Please note: ** phones support FSK and / or DTMF only in the countries for which they were designed.
