Here is a list of the medals you can earn in lockdown:
Mercenarie-100 kill
Purple heart-100 deaths
Interceptor-killed canister carrier 100 times
Biohazard-scored canister 100 times
Communications-250 conquest takeovers
Attendance-been on everyday for a week
Sharpshooter-90% accuracy for 20 games straight
Equipment-used every explosive twice in 1 server and gas mask.
Mine-planted 500 claymores
Veteran-played every game type on every map
Valor-win 20 consecutive clan matches