Document from the year 2020 in the subject Computer Science - Technical Computer Science, grade: 15, , course: COMPUTER NETWORKS, language: English, abstract: SDN need can be explained with the help of real life analogy corresponding to water supply system. Water reservoir has pipes (data cables) attached to it to carry water (data) to the destination. Water regulation is done with the help of numerous valves (routers and switches).Plumber (network admin) is the in charge of addition, up gradation of pipes and valves. As the pipe changes, corresponding valves need to be changed. This is costly and time consuming process, which causes lot of overhead in case of frequent infrastructural updates as the valves need individual-manual intervention. Bulk updation may cause installation errors or are more likely to faulty installations. Considering the above scenario it is desirable to have remotely controlled updation (increased width, new connections, extensions etc) regarding the pipe (data cables)& valves (switches and routers). So if this analogy is applied to real networking scenario, the SDN concept comes in picture. SDN provides programmable switches& routers which can be controlled remotely and will not require any manual intervention.