Question: Who can issue a digital signature certificate to a subscriber?

Ans: A Certifying Authority can issue a digital signature certificate to a subscriber. The ICT Act, 2006 and the Certifying Authority can make the rules framed under the Act stipulates the methods for issuance of a digital signature certificate.
See More
Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), pp. 106-107.
And read more, the following suggested readings are enlisted here:
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Question: When can a digital signature certificate be revoked?

Ans: See  Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), pp. 108-109.
And read more, the following suggested readings are enlisted here:
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Question: What other provisions/Acts are not covered under the ICT Act?

Ans: Sec 87 of the ICT Act, 2006.
See more: Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), p. 154 & p. 69.
And read more, the following suggested readings are enlisted here:

Question: What other provisions/Acts are not covered under the ICT Act?

Ans: Sec 87 of the ICT Act, 2006.
See more: Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), p. 154 & p. 69.
And read more, the following suggested readings are enlisted here:

Question: What are the functions of Controller?

Ans:
See  Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), pp. 101-102.
And read more, the following suggested readings are enlisted here:

Question: What are the criminal offences stipulated by ICT Act 2006?

Ans:
See  Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), p. 139.
And read more, the following suggested readings are enlisted here:

Question: What are the civil offences stipulated by ICT Act 2006?

Ans:
See  Dr. Zulfiquar Ahmed, A Text Book on Cyber Law in Bangladesh, (Dhaka: National Law Book, 2009), p. 138.
And read more, the following suggested readings are enlisted here: