View All num of num See all Photos Bsnl This employer has taken extra steps to respond to reviews and provide job seekers with accurate company information, photos, and reviews. Interested for your company?Learn More. www.bsnl.co.in www.bsnl.co.in Work in HR? Unlock Free Profile Overview Reviews Salaries Interviews Jobs Photos Benefits 155 Reviews 98 Salaries 25 Interviews Follow Add Review or Salary Follow Add Review or Salary Bsnl 155 Interview Question Sub Divisional Engineer Interview Indore (India) Bsnl What is Signalling in telecom domain. Differentiate between CAS and CCS signalling. Tags: technical, logic, job-specific See more , See less 8 Answer Add Tags Flag as Inappropriate Thank you! Your feedback has been sent to the team and we'll look into it. Oops! We're sorry but your feedback didn't make it to the team. Your input is valuable to us — would you mind trying again? Send Answer Interview Answer 1 Answer ▲ 1 ▼ Signalling is the transfer of any signal ( notification of event ) from one end to another. In telecom we use signalling for Call Establishments, termination, routing, charging etc.CAS Signalling- It is channel associated signalling. As name indicates, it follows the same path of the voice channel. It is basically register signalling and it is slow compare to CCS signallingCCS Signalling- It is Common Channel Signalling. It is also names as CCS7 or SS7. It is using layered architecture similiar to TCP/IP layer protocol. It is very fast and efficient signalling. Now a days almost all telecom exchanges are using CCS 7 Signalling. Interview Candidate on Jul 5, 2012 Flag as Inappropriate Thank you! Your feedback has been sent to the team and we'll look into it. Oops! We're sorry but your feedback didn't make it to the team. Your input is valuable to us — would you mind trying again? Send Add Answers or Comments To comment on this, Sign In or Sign Up.