Cryptography

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Questions derived from the CISSP – CISSP ISC2 Self-Test Software Practice Test.

Objective: Cryptography
SubObjective: Understand the application and use of cryptography

Item Number: CISSP.4.1.8
Single Answer, Multiple Choice

Which function is NOT performed at the Physical layer of the OSI model?

1. Defining the size of the Ethernet cable
2. Defining the type of connector being used
3. Defining the type of encryption being used for the data
4. Defining the electrical features of the communication media

Answer:
C. Defining the type of encryption being used for the data

Tutorial:
The data encryption method being used is not defined at the Physical layer of the OSI model. Data Encryption is supported at the Data-Link, Network, Transport, Session, and Application layers of the OSI model.

The Physical layer deals with electrical impulses, light and radio signals, physical cables, cards, and other physical aspects of the communication medium. Defining the type of connectors being used and the size and distance limitations of the Ethernet cable are some other functions performed at the Physical layer.

Reference:
Wikipedia.org, OSI model, http://en.wikipedia.org/wiki/OSI_model