Teleservices and Bearer Services

Teleservices are defined at the user interfaces but the bearer services at the network interfaces of the terminal equipment as can be seen in figure 5.3.1.:

• teleservices are telecommunication services which provide full communication in between users according to the agreed protocol of network operators including the terminal equipment functions

bearer services are telecommunication services providing the signal transmission capabilities in between network access points

Teleservice

Bearer service

w

w

Terminal

Telecom network

Terminal

Fig 5.3.1 Definitions of teleservices and bearer services

Fig 5.3.1 Definitions of teleservices and bearer services

Bearer services have not direct connection to the end users, but have importance to connect correctly terminal equipment. So concerning applications the barrier services have only secondary importance and there will be presented by some examples.

The ISDN bearer services include:

• 64 kbit/s, unrestricted, 8 kHz, structured circuit-mode bearer service,

• alternate speech and 64 kbit/s, unrestricted, 8 kHz, structured, circuit-mode bearer service,

• virtual call and permanent virtual circuit packet-mode bearer service Teleservices are directly used by end users. The benefits of standardised teleservices are the smooth interworking of network operators, economy of scale in manufacturing and selling terminal equipment which means safe and cheap communication.

The widely spread ISDN teleservices are:

• telephony - providing two-way real time conversation on the network in between users,

• teletex - transmission of documents as teletex coded information from memory to memory on the network,

• G4 telefax - transmission of documents using Group 4 faximile coding on ISDN

• videotex - access and downloading text and graphical information extended with mailbox functions,

• 7 kHz telephone - good quality two-way real-time voice transmission using 507000Hz bandwidth on ISDN

The most popular standardised GSM teleservices:

• emergency calls

• short messages - terminated in the handset (SMS MT/PP)

• short messages - initiated by handset (SMS MO/PP)

• short messages - broadcasted within the cell (SMS CB)

• alternated voice and telefax G3

• automatic telefax G3

Some details concerning the teleservices listed above are the followings.

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Responses

  • frank
    What is bearer service in ISDN?
    1 year ago
  • LIVIANA
    Which is good telecom bearer?
    18 days ago

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