video card, network card etc. were separate extension card based. Cartridge DX 200: Computer units are standalone cards. Similar to modern PC architecture, where "everything" in integrated to the mother board. ATCA DX 200: Advanced Telecommunications Computing Architecture industry standard hardware. IPA2800: A specific version of Cartridge DX 200, suitable for very high throughput real-time media processing and transmission. Typical applications are Media gateways and Radio Network Controllers. Reborn Nokia Networks shifted its focus from hardware products to software and services. The highly valuable business logic was kept, while the products which used to be running on DX 200 hardware variants now available as cloud solutions, working on generic multi-purpose hardware of various vendors. The first generation of such products used virtual machines in place of DX 200 computer units. That software architecture supports virtual environments like Linux's KVM or VMware products. Resource usage dynamically adapts to needs, to have optimal performance while reducing costs. The next generation, in line with leading industry trends, is based on Linux, uses software containers, focused on microservices, dynamic service discovery and orchestration. In place of live migration offered by TNSDL language session data are stored in distributed database. While live migration happened from a certain computer to another one, in the new architecture those sessions may be moved to different containers, thus allowing scaling in (reducing the number of containers and VMs) in the system. And session data being stored in more generic serialized format (e.g. JSON) instead of binary structures allows more relaxed version updates. History Development of the system started at Televa, the Finnish state owned telecom equipment producer in the early 1970s, under the leadership of Keijo Olkkola. The first order was received in 1973 for a 100 subscriber local exchange for the small and remote island community of Houtskär, to be delivered in 1979. After the first installation in 1982, the DX 200 captured a 50% share of the Finnish fixed line exchange market. The exchange's modular design and development of microprocessors technology enabled a gradual increase in the system's capacity. By 1987 the installation base had grown to 400,000 subscriber lines. Early export markets included China, Nepal, United Arab Emirates, Sri Lanka, Sweden, Turkey and the Soviet Union. In 1984 development of a version of the exchange for the Nordic Mobile Telephone network was started. In 1991, the world's first GSM call was made using Nokia devices. Core