auxiliary operation vs off-line operation

auxiliary operation and off-line operation both are nouns.

Word	Noun	Adjective	Verb	Adverb
auxiliary operation	Yes	No	No	No
off-line operation	Yes	No	No	No

As nouns, auxiliary operation and off-line operation are synonyms defined as:

auxiliary operation and off-line operation: a operation performed by off-line equipment not under the control of the central processing unit

auxiliary operation (noun)	off-line operation (noun)
a operation performed by off-line equipment not under the control of the central processing unit	a operation performed by off-line equipment not under the control of the central processing unit