Which of the following is associated with the term Enterprise Systems Connection? (Choose all that apply)

A.
ESCON switch

B.
Black box

C.
Director

D.
None of the above

Explanation:
The term Enterprise Systems Connection (ESCON) comes from the IBM mainframe marketing world. It refers to the highly available, though relatively simple to configure, ESCON switches (also called black boxes or directors) that first connected servers and storage devices.
References:
Charles J. Brooks, Server+ Certification Exam Cram 2 (Exam SK0-002), QUE Publishing, Indianapolis, 2006, pp. 283-290.