Cryptography is sometimes said to be brittle, in the sense that it can be very strong, but when it breaks, it (generally) completely shatters. In contrast, some security features can "bend" without...

Cryptography is sometimes said to be brittle, in the sense that it can be very strong, but when it breaks, it (generally) completely shatters. In contrast, some security features can "bend" without breaking completely—security may be lost as a result of the bending, but some useful level of security remains.

a. Other than cryptography, give an example where security is brittle.

b. Provide an example where security is not brittle, that is, the security can bend without completely breaking.