2 Is the Lamport hash protocol vulnerable to dictionary attack by an eavesdropper? Can some- one impersonating the server do a dictionary attack?

The National Security Agency of the United States developed the SHA1 hashing algorithm. What are the potential downsides of its use?

Which ADT table implementations performs better on the average if the retrieve operation is the major operation of the applications, balanced binary search tree or hash table? Why? Which ADT table implementations is most appropriate if the application requires every single retrieve operation to be done efficiently, balanced binary search tree or hash table? Why? (Think of an emergency system that cannot allow an unpredictable delay from any single retrieval.)

What is the benefit of hash index table?