Computer Laboratory

Technical reports

Access control for network management

Dongting Yu

January 2017, 108 pages

This technical report is based on a dissertation submitted May 2016 by the author for the degree of Doctor of Philosophy to the University of Cambridge, Robinson College.

Abstract

Network management inherently involves human input. From expressing business logic and network policy to the low level commands to networking devices, at least some tasks are done manually by operators. These tasks are a source of error whose consequences can be severe, since operators have high levels of access, and can bring down a whole network if they configure it improperly.

Software-Defined Networking (SDN) is a new network technology that brings even more flexibility (and risk) to network operations. Operators can now easily get third-party apps to run in their networks, or even host tenants and give them some control over their portion of the network. However security has not caught up, and it is easy for these third parties to access network resources without permission.

Access control is a mature concept; it has been studied for decades. In this dissertation I examine how access control can be used to solve the above network management problems. I look at the Border Gateway Protocol (BGP) from an operations perspective and propose a mandatory access control model using role-based policies to separate long-term invariants from day-to-day configurations. As a result the former would not be accidentally violated when configuring the latter, as this is a significant source of BGP misconfigurations today. Then, for SDN, I propose to add access control to controllers so that virtual controllers and applications that run within them cannot have unlimited access to the network infrastructure, as they do currently. Adding attribute-based access control makes the system much less fragile while it still retains the essential flexibility provided by SDN. Lastly, I propose a hierarchical architecture which, with SDN, can isolate security compromises even when some devices are physically compromised. This is achieved by using access control to both enable network access and deny unexpected connections.

Full text

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BibTeX record

@TechReport{UCAM-CL-TR-898,
  author =	 {Yu, Dongting},
  title = 	 {{Access control for network management}},
  year = 	 2017,
  month = 	 jan,
  url = 	 {http://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-898.pdf},
  institution =  {University of Cambridge, Computer Laboratory},
  number = 	 {UCAM-CL-TR-898}
}