[5]: 7 The satellites are designed to identify any possible future ballistic missile launches, from outer space, and complement early warning radars such as the Voronezh.
[10] Oko has two types of satellites: US-KMO are in geosynchronous orbits and have an infrared telescope to identify ballistic missile launches.
[8]: 40 [8]: 52 Oko is part of the Main Centre for Missile Attack Warning[13] which is under the Space Command (KK) of the Russian Aerospace Defence Forces.
[1][6] Information on the new EKS system is scarce but it appears that it was designed by Energia Corp in 1999-2000 and was selected against a proposal from Oko manufacturer NPO Lavochkin.
[20] In 2011, the Russian MoD sued Energia for the delay, claiming that a contract extension issued until May 2010 was invalid and asking for 262 million rubles in compensation.
[24] The first EKS satellite (Kosmos 2510, EKS-1, Tundra 11L) was eventually launched from Plesetsk on 17 November 2015 using a Soyuz-2.1b rocket[2] and as of May 2020[update] there were four in service which is the minimum standard strength.