[Q.46] In TCP sliding window protocol, if window size is N, sender can transmit up to:
Sliding window permits N unacknowledged frames in transit.
[Q.47] Which encryption algorithm is an asymmetric (public key) cipher?
RSA is an asymmetric cipher; AES, DES, Blowfish are symmetric.
[Q.48] Which HTTP status code indicates '404 Not Found'?
404 indicates the requested URL/resource was not found on the server.
[Q.49] In symmetric key cryptography, if 'n' users wish to communicate securely pairwise, how many secret keys are required?
Pairwise symmetric keys = C(n,2) = n(n-1)/2.
[Q.50] Which protocol operates at the Application Layer of OSI model to securely transfer web pages?
HTTPS is an Application layer protocol combining HTTP with TLS/SSL encryption.