Classification is placed on transmissions sent and received by UNSC personnel in order to determine the extent of restriction that is to be placed on the information contained in the transmission. The information can have varying degrees of importance, which can also be determined by the transmission's Encryption Code.
BGX Directive: Under this directive, it appears a communique should be classified as restricted when officers wish to communicate with one another. As well, sharing of the Cole Protocol falls under the restricted classification, even to broad groups of Navy Personnel.
XXX-XD Directive: Under this directive, it appears communique should be rated restricted when a UNSC AI communicates with an officer.
BGX Directive: Under this directive, this classification is also used by military personnel to communicate with one another. More specifically, it is used when one commander wishes to communicate with as many UNSC ships as they can within range while still maintaining a level of secrecy.
BGX Directive: Under this directive, this classification is for a higher-level of secrecy. It is designed to be used exclusively when ship captains communicate with one another, or when Admirals wish to communicate with lower ranking ship commanders.
BXG Directive, Cole Directive, General Directive: Under all three of these directives, this classification is used for communication between Senior officers, about SPARTAN deployment.
SECTION III X-RAY DIRECTIVE: Under this directive, this classification is to ensure that no one is supposed to see the information on the file except the sender and the recipient. It is used exclusively by members of ONI Section Three.