Enhancing the BRAS through virtualization

Broadband Remote Access Servers (BRASes) are crucial middleboxes in DSL access networks, providing the first IP point in the network for subscribers and enforcing operator policies. The number of functions provided by BRASes, combined with the key role they play in the network, means that these devices are expensive, difficult to change, and constitute a single point of failure. In order to overcome these limitations, we propose to virtualize the BRAS and to enhance it with a control interface that can be exploited by management systems in order to introduce live session migration and higher reliability. Our proof-of-concept implementation shows that our virtual software BRAS is able to handle thousands of sessions while forwarding and shaping traffic at rates of millions of packets per second on commodity hardware, and that the live session migration feature enables the implementation of high-reliability scenarios.