Defense Red Switch Network
![A Multi Line Phone (MLP-1A), made by Electrospace Systems, which was part of the Defense Red Switch Network since 1983. The phone has the four extra MLPP buttons and 48 programmable buttons for access to both secure and nonsecure lines.[1]](/Images/godic/202501/10/Electrospace-mlp1a1432.jpg")
The Defense Red Switch Network (DRSN) is a dedicated telephone network which provides global secure communication services for the command and control structure of the United States Armed Forces. The network is maintained by the Defense Information Systems Agency (DISA) and is secured for communications up to the level of Top Secret SCI.