Outsourcing Routing using SDN: The Case for a Multi-Domain Routing Operating System

The art of routing encompasses many more skills than the mere knowledge of how a routing protocol works. This includes the optimization of traffic flows via traffic en-gineering, correctly mapping Service Level Agreements (SLAs) to policies and then to low-level distributed configuration, coping with errors and scalability issues, while at the same time properly securing the network. Each of these oftentimes competing goals re-quires tuning several knobs in the routing protocol. Therefore, optimizing how packets are routed within an ISP to satisfy numerous operational and economic objectives is a very challenging problem. Although a number of advanced traffic engineering techniques have been proposed, for example based on integer-programming and multi-commodity-flow op-timization, network domains are usually run based on simple best practices that do not necessarily meet all the specific needs of an ISP. In addition, the router configuration code an ISP needs to develop, debug, and update is extensive, while the manual configuration of routers requires many work-hours and is an error-prone process. In this work, we propose the unconventional idea of outsourcing the routing control logic of an ISP to an external trusted provider, i.e., the service contractor1. Outsourcin