Data over signalling (sometimes data over signaling) or DoS, is a technique in

telecommunications Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...

in which primary

data Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted for ...

is sent over a signalling channel instead of the subscriber's

bearer channel A bearer channel is a DS-0 that carries call content i.e. one that does not carry signaling. In the common-channel signaling scheme for telecommunications, signaling is sent out-of-band, while all other traffic rides bearer channels. When a c ...

Background

Data over signalling was designed as a solution to the problem of transceiving simultaneous voice and data. Data over signalling can be utilized when the signalling channel is either channel associated or

common Common may refer to: As an Irish surname, it is anglicised from Irish Gaelic surname Ó Comáin. Places * Common, a townland in County Tyrone, Northern Ireland * Boston Common, a central public park in Boston, Massachusetts * Cambridge Com ...

. However, it is easier to implement when the signalling channel is channel associated, as the system does not have to demultiplex the data and signalling between multiple subscribers. DoS was designed so that mobile telephony subscribers could maintain a voice session on their bearer channel while still accessing data related services, such as

text messaging Text messaging, or texting, is the act of composing and sending electronic messages, typically consisting of alphabetic and numeric characters, between two or more users of mobile phones, tablet computers, smartwatches, desktops/laptops, or ...

References

Telecommunications techniques Data transmission Telephony {{telephony-stub