Complex sentence: As a high-assurance, MLS system, XTS-400 can be used in "cross-domain solutions", which typically need a piece of privileged software to be developed which can temporarily circumvent one or more security features in a controlled manner.
Split into simpler sentences: As a high-assurance, MLS system, XTS-400 can be used in "cross-domain" solutions. A cross-domain solution will typically require a piece of privileged software to be developed which can temporarily circumvent one or more security features in a controlled manner.