A Policy-aware Switching Layer for Data Centers

This paper addresses the need for more control over middlebox traversal in today's data centers. Data centers use a variety of middleboxes to improve the performance and security of services but existing networks provide suboptimal means to coerce traffic through a specific path of middleboxes. For this reason, the authors propose a policy-aware layer (PLayer) for data centers that is flexible, efficient and resilient to stern network conditions. Essentially, the solution is to wrap another layer of headers on each ethernet frame in order to track its progress through the policy (intended series of middleboxes).

In many ways, the ideas here are similar to the one that advocated a smoother integration of middleboxes into the Internet backbone by adding new identifiers. However, the solution proposed here appears to integrate rather seamlessly and with less overhead. The applications are also very obviously relevant (unlike the other middlebox paper, which didn't have a very convincing motivation in my opinion) and the concepts are generally explained clearly. I didn't completely understand the use of MAC addresses for pswitch-routing.