These appear to be concept designs of GDI troops.
The weaponry bears some resemblance to the Heckler & Koch XM-8 Battle Rifle, and the system as a whole shares some striking comparison to the U.S. Army's Future Force Warrior program.
As a reference, the U.S. Army's Future Warrior program is the closest comparison to Tiberian Sun's concept of a future soldier.
Note the assault vest on the left and the body armor on the right.
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