PLS ATTEMpT ALL QUESTIONS WITH NO PLAGIARISM

1. Consider two different worlds with respect to cryptographic applications:

World 1: the early 1970s;

World 2: today.

The cryptographic applications discussed in this chapter belong to the second of these worlds (indeed, many were unimaginable in the first of these worlds). At a fairly high and generic level, compare these two worlds by considering the following issues for each of them. In each of the two worlds:

(a) Who is using cryptography and for what applications?

(b) What type of cryptography is deployed?

(c) What security services are implemented?

(d) What technology is used to conduct cryptographic operations?

(e) How secure is a typical communication channel?

(f) How secure are the end points (the sender and receivers local environ- ments)?

(g) How reliable are the cryptographic mechanisms that are used?

(h) How straightforward is key management?

(i) Are there any security issues relating to cryptography in the first world that do not apply to the second world?

(j) Are there any security issues relating to cryptography in the second world that do not apply to the first world?

(k) Summarise the discussion by commenting on whether the role and effectiveness of cryptography has changed between these two worlds.