From Path of the Vampire Wiki
When entering a system during a hack you will encounter one of nine layouts, commonly referred to as system maps. Each 'node' is represented by a square on the maps below. Each node has a specific function and is protected by a specific type of countermeasure - in order to combat these, scripts are required.
You will always start your hack in the Gateway node at 10_10 of any system.
|Node||Type||Protection||Scripts required (optional)|
|F||File||Tracer (sometimes)||Decrypt, Transfer, (Silence/Delete)|
|G||Gateway||Authentication, Sentinel||Mask, Stealth, (Delete)|
|S||Security||Authentication, Sentinel, Warrior, Triangulate||Mask, Stealth, Armor, Silence, (Delete)|