SOP
From the Metal Gear Wiki
SOP (standing for Sons of the Patriots, sometimes referred to as simply "The System") is an advanced system controlled by The Patriots' proxy-AI systems that allows the government to track and keep check on every soldier deployed in combat action by using and controlling the nanomachines that are inside every soldier (incluiding state militaries and PMCs). It was developed by ArmsTech Security after the Manhattan Incident in 2009.
SOP serves three main functions. The first is to allow multiple members of a military unit to share each other's senses and work more efficiently as a team. The system basicly runs a unit like a network of computers, each man able to see what the others see, feel what they feel, and rapidly (split second in some instances) corrdinate tactics. This provides a massive tactical advantage to whomever uses it.
The second function is to monitor the chemical balance of every soldier engaged in combat action. This allows the nanomachines to induce an artificial "combat high" by controlling the release of adrenaline and endorphins, elevating the senses and accuracy of every soldier. Furthermore, it allowed accurate monitoring of a soldier's oral intake and excrements (water, food and sweat). This refined information allowed commanders to make more informed decisions on the flow of combat. Soldiers under SOP also have their emotions suppressed so that they feel less fear and remorse than other soldiers might. One's sense of pain is subject to the same treatment, stopping minor injuries from getting into the way during combat (allowing, for example, a soldier to get shot in a minor place without even flinching).
The third main function of SOP is to monitor and control the use of weapons on a battlefield. As every soldier's personal weapons (save for the few "naked guns") are "ID Locked" to them as a result of the SOP system, only authorised individuals soldiers can use that locked weapon. It can also prevent soldiers from firing on their own, and stops them from committing atrocious acts and violating human rights. Although the intended function is to prevent PMCs from attacking their own clients. SOP governs all small arms and ammunition, as well as vehicles like helicopters and tanks. It does not, however, govern anything larger than small arms, leaving weapons such as missiles locked for usage by a higher-authority system.
As of 2014, all state armies and PMCs are known to have the SOP implanted in them and even law enforcement agencies and paramilitaries were adopting them. Of course, militias and rebel armies did not have access to the system, which explains why they lost many battles to state armies. Meryl's Rat Patrol 01 team is one example.
[edit] Liquid Ocelot's Insurrection
See Liquid Sun, Solid Sun, Third Sun, Twin Suns, Old Sun and Naked Sin
Liquid Ocelot, being the head of the PMC Mother Company Outer Heaven, had built an army with enough firepower to rival the US Military and was intending to use this massive army to challenge The Patriots. However, thanks to the limitations of the system he was unable to attack them as he knew they would simply lock his entire army down. What Liquid originally intended to do was take the system offline, but to do this he required the cells of Big Boss which acted as a key to the system. He conducted two tests on his own PMC troops, one in the Middle East and one in South America using his own cells and the cells of his "brother" Solid Snake respectively. While both these tests partially succeeded, the withdrawal from the system drove the troops to the brink of insanity, as they were unable to cope with the emotions and memories that had before been suppressed, some even suffering fatal heart attacks from the shock.
Even though Liquid had pieced together the broken GW AI, it was not enough to access SOP directly. He later "stole" Big Boss' corpse from Big Mama and used it to fully gain control of SOP (it was later revealed that the corpse was actually the corpse of Solidus Snake, but his genes were identical to that of Big Boss, so they worked just as well. It was also later revealed that Big Mama was also in league with Ocelot as well, and that the theft was both their ideas.). With SOP under Liquid's control (renamed "Guns of the Patriots" by him), private armies around the world were crippled, leaving only Liquid's own PMCs unaffected.
The Sons of the Patriots system was destroyed by the FOXALIVE virus created by Naomi Hunter and Sunny, along with the rest of the Patriots' AI matrix. However, with the system destroyed, this would also cripple PMCs as well as state armies worldwide, leaving behind a uncertain fate.
[edit] Metal Gear Online
In Metal Gear Online, the SOP system allows players to see where their teammates are at any given time and allows them to know if an ally has fallen into a trap, needs backup, has been killed/stunned, and the exact location, however the system needs to be activated by standing next to a comrade and pressing/holding the Triangle button. In addition, if one accidentally shoots their own teammate, the system will lock the gun, preventing them from firing for a few moments.
As well as being a gameplay tool, SOP can also be used by the opposing team. A player can capture an enemy and hack into their SOP system using a Scanning Plug to allow them to see all enemies linked to the one being scanned. Additionally, during the Base Mission mode, payers can buy an "SOP Destablizer", which, when placed on the enemy base, will render all opposing players unable to move or attack for 30 seconds, similar to how Guns of the Patriots worked.
