Türk Telekom

ISDN PA subscription is proper for file transfer, LAN connections, visual communications, PC communication, internet service providers and for big companies; ISDN BA is proper for more small and medium sized enterprises and home users.

ISDN BA (128 Kbps) is sufficient for videophone. Voice is transferred through one of the B channels and video is transferred through the other one. However, since ISDN PA (2 Mbps) is a very large bandwidth, it is not economical for only videophone.

When ISDN BA and ISDN PA are considered, B channels are used for voice or data; and D channels are used for signalling or X.25 package network. There are 30 B and 1 D channels on ISDN PA. Its rate is 2 Mbps. In fact it is based on E1 interface. According to Japanese standard, it operates in the same environment with 24 channels and 1.54 Mbps, in other words T1. It is generally used for connection between PBX of big companies and Türk Telekom exchange.

For a faster internet access, where you can take advantage of gradually increasing voice, video and multimedia data, ISDN BA provides more effective and economical connection with connection within a few seconds and at 64 or 128 kbps access rate.

While the transfer is done at 28.8 Kbps with standard V.34 modem over existing telephone lines, this speed goes up to almost 4 times of it, 128 Kbps, at ISDN without compression. When compared to 14.4 Kbps (V.23 bit) modem, your speed is increased approximately 10 times.

Three main elements are needed:
ISDN line supplied by our company
ISDN equipment
ISDN Internet Service Provider

No. To use ISDN line, ISDN card or terminal adaptor is needed.

MSN-Multiple Subscriber Number:

It is the feature to have the same number for each device (maximum 8 terminals) to connect ISDN line or to use more than one numbers for one terminal device.

DDI-Direct Dialling In:

It is the feature which the callers can reach subscriber by dialling Prefix + extension.

Sub Addressing:

It is the feature that the subscriber can define logical addresses for terminal devices. With the digits to be defined after telephone number, more than one addresses for a single ISDN number will be identified to the devices connected to line.

User To User Signalling- UUS:

It is the feature of performing transfer of short message or scaled data by using D signalling channel.

AOC- Appraisal of Charge:

It is the feature of seeing charge information or credit amount related to call, during establishing call, during call or at the end of the call.

CUG- Closed User Group:

It is the feature that one or more than one certain group members communicate with each other over a special virtual network.

CLIR- Calling Line Identification Restriction:

It is the feature that seeing the caller's number by the other party can be restricted.

COLP- Connected Oriented Link Protocol:

It is the feature that the connected terminal’s number can be seen. It can be used in the cases especially when the device (fax etc.) of the called party is not available, or when confirmation for if the sent data was transferred to the right place or not.

COLR- Connected Line Identification Restriction:

It is the feature that restricts sending the number information of the called subscriber to the calling party. CLIP- Connected Line Identification Presentation:
It is the feature that the number of the calling subscriber is seen. It is a feature that the called subscriber would receive.

Call Hold:

It is the feature that the subscriber puts the subscriber that he/she speaks on hold and makes another call.

Call Barring:

Restriction of Outgoing Calls is a feature that the subscriber may switch it on or off for all or definite outgoing calls.

Call Waiting:

It is the feature that the subscriber is informed about an incoming call with a warning tone when he/she is engaged. The subscriber either puts the call on hold and establishes connection with the new caller or chooses one of the calls and ends the other.

Call Forward B / U / NR:

• It is the feature that the incoming calls are diverted to numbers that defined earlier. Call diversion can be done in three different ways:
• Subscriber is engaged – B: Incoming calls are diverted if the subscriber is engaged.
• All Calls – U: All incoming calls are diverted.
• No Response – NR: Incoming calls are diverted if there is no response although ring tones at a number that defined earlier were ringed.

Conference Calling:

It is the feature that more than two subscriber can call each other.

Terminal Portability:

It is the feature that the subscriber parks his/her terminal device, while communication (connection) is still continuing, and plugs it to another socket connected to the same access and continues his/her call or communication from where he/she left.

Call Transfer:

It is the feature that an incoming call to the subscriber is transferred to another subscriber.

MCID- Malicious Call Identification:

It is the feature that disturbing calls can be located from the exchange.

CCBS- Call Completion on Busy Subscriber:

It is the feature that in case that the number that is called is engaged, the call is performed automatically when the number is not engaged any more.

Line Hunting:

It is the feature that incoming calls are dispersed in the order that is defined earlier.

In order to display the Undertaking of ISDN Service Level that contains the methods, principles and standards related to the processes of availability, application, allocation and establishment of this service, click. PDF