Central Control Over Distributed Routing – Public Review

Modern network management is foremost a case of precise control: to implement practical traffic engineering and network security policies, a network operator needs to control the exact path traffic takes through a network. While conceptually simple, accomplishing this level of control is surprisingly difficult with traditional network control planes; in the end, the underlying distributed routing protocols provide the operator only with indirect controls over the traffic forwarded. Indeed, it was this inadequate control that motivated SDN and its wholesale departure from these proven, but distributed protocols.