Date Added: Aug 2012
Middleboxes are ubiquitous in today's networks and perform a variety of important functions, including IDS, VPN, firewalling, and WAN optimization. These functions differ vastly in their requirements for hardware resources (e.g., CPU cycles and memory bandwidth). Thus, depending on the functions they go through, different flows can consume different amounts of a middlebox's resources. While there is much literature on weighted fair sharing of link bandwidth to isolate flows, it is unclear how to schedule multiple resources in a middlebox to achieve similar guarantees. In this paper, the authors analyze several natural packet scheduling algorithms for multiple resources and show that they have undesirable properties.