Chapter 1: X.800 Security Services

Question 1

What does it say about authentication and what are the two types of authentication?

Answer 1

Authentication: the assurance that the communicating entity is the one that it claims to be.

Peer-entity: provide confidence in the identity of the entities connected. Peer = two entities that implement the same protocol. Used at the establishment of or during the data transfer phase of a connection.

Data-origin: in a connection-less transfer, provides in the source of received data. Provides no protection against tampering

Question 2

What does it say about access control?

Answer 2

The prevention of unauthorised use of resources.

NETSEC: the ability to limit and control access to host systems and applications via communication links

Question 3

What does it say about data confidentiality and what types of confidentiality does it mention?

Answer 3

The protection of data from unauthorised disclosure.

Connection: the protection of all user data on a connection

Connection-less_ the protection of all user data in a single data block

Selective-field:
The confidentiality of selected field within the user data on a connection or in a single data block

Traffic-flow: the protection of the information that might be derived from observation of traffic flows.

Question 4

What does it say about data integrity and what types of integrity does it list?

Answer 4

Data integrity: the assurance that the data sent by an authorised entity has not been tampered with.

Connection integrity with recovery:
Provides integrity for all users on a connection and detects tampering and replay of data, with recovery attempts

Connection integrity without recovery:
Same as above but without recovery.

Selective-field connection integrity:

Connection-less integrity: provides integrity for single connection-less data block and may take the form of detection of tampering. Limited replay detection may be provided as well.

Selective-field connection-less integrity: provides integrity for selected fields within a single connection-less data block; takes the form of determining if the field has been tampered with

Question 5

What does it say about non-repudiation and what two types does it list?

Answer 5

Non-repudiation: Provides protection against denial by one of the entities involved in a communication of having participated in all or part of the communication

Origin:
Proof that the message was sent by the specified party

Destination: proof that the message was received by the specified party.