Company XYZ has just purchased Company ABC through a new acquisition. A business decision has been made to integrate the two company's networks, application, and several basic services. The initial…

Having Company ABC manage the firewall placed at Company XYZ's hub site ensures that access to ABC's internal resources - including the web intranet, file, print, SFTP servers, and authentication domain - is controlled by the trusted party rather than the partially trusted XYZ. Positioning the firewall at XYZ's hub site minimizes round-trip latency for XYZ users, addressing the performance requirement. This architecture satisfies both the partial-trust constraint and the onboarding of XYZ into ABC's authentication domain.

Allowing XYZ to manage the router ACLs controlling access to ABC's systems contradicts the partial-trust designation, as a partially trusted party should not control its own access permissions to the trusted party's resources.

Placing no restrictions on internal connectivity ignores the partial-trust requirement entirely and establishes no security boundary between the two companies' networks.

Placing servers at XYZ's hub site without ABC-managed access controls does not address the authentication and trust requirements and introduces risk by moving sensitive ABC resources into a less trusted environment.