Sign In

Communications of the ACM

Research highlights

Technical Perspective: Treating Networks Like Programs

Why are my packets being dropped? Why does my Internet connection keep resetting? Programmers developing software have access to a panoply of tools including compilers, debuggers, static and dynamic checkers. Unfortunately, network operators have access to only crude tools such as TraceRoute and Ping. These tools have remained unchanged for decades while networks have grown increasingly complicated: load balancers spread traffic using unknown hash functions, and firewalls interdict messages based on cryptic rules that human operators enter, sometimes incorrectly. In a world of services accessed from tablets and mobile devices, network failures are a debilitating source of operational expenditures.

On the surface, networks with their collections of routers, switches, network interface cards, and cabling do not resemble code. But one can view the entire network as a "program" that takes packets from the input edges of the network and outputs packets to the output edge after possibly rewriting the packet. The forwarding table at routers can, for instance, be viewed as a large Switch statement across destination addresses.


No entries found

Log in to Read the Full Article

Sign In

Sign in using your ACM Web Account username and password to access premium content if you are an ACM member, Communications subscriber or Digital Library subscriber.

Need Access?

Please select one of the options below for access to premium content and features.

Create a Web Account

If you are already an ACM member, Communications subscriber, or Digital Library subscriber, please set up a web account to access premium content on this site.

Join the ACM

Become a member to take full advantage of ACM's outstanding computing information resources, networking opportunities, and other benefits.

Subscribe to Communications of the ACM Magazine

Get full access to 50+ years of CACM content and receive the print version of the magazine monthly.

Purchase the Article

Non-members can purchase this article or a copy of the magazine in which it appears.