Communications satellite
From Halopedia, the Halo wiki
Template:FOF-1 Communication satellites (COM Sats) are small, automated satellites placed in orbit around UNSC colonies and space to relay COM signals.
They are found in orbit above several major UNSC worlds, including Earth, Reach, and Sigma Octanus IV. They can be accessed through the planetary network, and AIs such as Cortana have done so for various purposes.