Ok in thee story of halo the one thing that protected earth was Cole Protocol. It was the most important of one thing in the UNSC as it made sure no matter the cost Earths Location would not be found.
For those who dont know the Protocol was that in the case of a ship in UNSC hands getting into the clutches of the Covenant and managed to take data from it or got rather close to its data banks all Memory on the ship would be wiped ad it would self destruct.
Now heres how the idea works into game. when a Boarding party is sent a latches onto a ship theres a chance it will be lost, if lost for any moment of tiem to the enemy they will get a complete map of all your planets including their defenses and buildings (not how many ships are located at that planet)
This could be a huge advantage for the enemy
UNSC players however could get Cole Protocol unlocked in the Military Branch of Research, Where if a Boarded vessel is claimed or gets close to it will simply self destruct, note this will only be for capital and large frigates, small frigates will not follow the same rule.
On the covies hand captured vessels will only display the world they were built at, nothing more.