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Integrated Solutions Digital Network (ISDN) is a postpaid solution currently available for corporate and business users in major cities.

ISDN is the digitalization of the access line between the exchange and the customer's premises, with a powerful signaling system associated with it.

The ISDN digital access provides the users with the possibility of initializing end-to-end digital connections that can support Voice, Data and a variety of added solutions. TTCL supports Primary Rate Access (PRA) 30B+D which has 30 bearer channels with 64kb/s capacity each and the solution is intended for those who want to connect ISDN PABXs.

ISDN solution is a fraud free solution and hence guarantees user a secure communication. TTCL enterprise use with ISDN solutions will also be able to use ISDN VAS solutions such as;

  • Calling Line Identification (CLI)
  • Multiple subscriber numbers (MSN)
  • Direct Dialing Inward (DDI)
  • Call forwarding
  • Conference call
  • Sub addressing (SUB)

Terms and conditions


How to Subscribe

Visit nearest TTCL customer Service office available countrywide or call 100 by using your TTCL line or Call 022 2100100 from any network