September/October 2011

ISA Certified Automation Professional (CAP) program

Certified Automation Professionals (CAPs) are responsible for the direction, design, and deployment of systems and equipment for manufacturing and control systems.

CAP question

Which of the following network security technologies does not use encryption?

A. Digital Signatures

B. Virtual Local Area Network (VLAN)

C. Virtual Private Network (VPN)

D. Wired Equivalent Privacy (WEP)

CAP answer

The correct answer is B. A virtual local area network (VLAN) is achieved through configuration of Ethernet switches and not encryption. It divides a physical network into smaller logical networks to increase performance, improve manageability, and simplify network design.

Answer A is not correct because digital signatures are encrypted. Information signed, such as a contract or data record, is compressed via a cryptographic one-way function (a hash) into a short bit string.

Answer C is not correct because a virtual private network (VPN) is an encrypted private network that operates as an overlay on a public infrastructure.

Answer D is not correct because Wired Equivalent Privacy (WEP) is an encryption algorithm for IEEE 802.11 wireless networks, originally intended to provide data confidentiality comparable to a wired network.

Reference: ANSI/ISA-TR99.00.01-2400 Security Technologies for Manufacturing and Control Systems