Space Development Agency (SDA)
The Space Development Agency (SDA) is a United States government entity that researches, develops, and fields next-generation technology for the United States’ Department of Defense’s National Defense Space Architecture.  The SDA was founded in March 2019 under the umbrella of the Undersecretary of Defense for Research and Engineering. The agency was designed to operate outside the existing architecture of the satellite acquisition system, i.e., to establish its own way of designing satellites, so that it could could establish itself as soon as possible. Key goals for the SDA include developing a LEO constellation (similar to Blackjack) and creating a surveillance mesh to track hypersonic glide weapons from unfriendly countries, namely China and Russia. 
For the LEO constellation, named JADC2, SDA released solicitations for 10 satellites to build the framework of its message transport layer. The idea behind JADC2 is to have a mesh of “sensors” and “shooters” operating all in space which will communicate information similar to a relay constellation. The end goal of JADC2 is to remove the ground station bottleneck across United States military programs and rely totally on optical links from a space-based sensor to its message transport layer. This will allow various military programs to skip ground station relays and use entirely space-based communications for exchanging information in one secure protocol, which differs from that of a traditional communications satellite network.  By 2026, it is expected that the SDA’s constellation will have global coverage. Currently, the SDA is an independent entity, but the United States Congress directed that the SDA be absorbed by the US Space Force no later than 2022.