Exam 14: Key Management and Distribution

Some sort of mechanism or protocol is needed to provide for the secure distribution of keys.

A __________ attack is when a protocol is insecure against an adversary who can intercept messages and can either relay the intercepted message or substitute another message.

A random number would not be a good choice for a nonce.

Each user must share a unique key with the key distribution center for purposes of key distribution.

Although public announcement of public keys is convenient, anyone can forge a public announcement.

For symmetric encryption to work the two parties to an exchange must share the same key and that key must be protected from access by others.

X.509 is an important standard because the certificate structure and authentication protocols defined in X.509 are used in a variety of contexts.

If A and B each has an encrypted connection to a third party C,C can deliver a key on the encrypted links to A and B.A _________ center is responsible for distributing keys to pairs of users as needed.

__________ indicates a restriction imposed as to the purposes for which,and the policies under which,the certified public key may be used.

The directory entry for each certification authority includes two types of certificates: forward certificates and ___________ .

With the __________ scheme,if an adversary succeeds in obtaining or computing the private key of the directory authority,the adversary could authoritatively pass out counterfeit public keys and subsequently impersonate any participant and eavesdrop on messages sent to any participant.

A __________ defines the procedures needed to revoke digital certificates.

A public-key certificate scheme alone does not provide the necessary security to authenticate the public key.

The topics of cryptographic key management and cryptographic key distribution are complex,involving cryptographic,protocol, and management considerations.

Communication between end systems is encrypted using a _________ key.

Key distribution often involves the use of __________ which are infrequently used and are long lasting.

If encryption is done at the __________ level a key is needed for every pair of users or processes that require communication.

Master keys can be distributed in some noncryptographic way such as physical delivery.

The strength of any cryptographic system rests with the ___________ .

__________ is the function that delivers a key to two parties who wish to exchange secure encrypted data.