Containers are in great demand because they are lightweight when compared to virtual machines. On the downside, containers offer weaker isolation than VMs, to the point where people run containers in virtual machines to achieve proper isolation. In this paper, we examine whether there is indeed a strict tradeoff between isolation (VMs) and efficiency (containers). We find that VMs can be as nimble as containers, as long as they are small and the toolstack is fast enough.

Video streaming dominates the Internet's overall traffic mix, with reports stating that it will constitute 90% of all consumer traffic by 2019. Most of this video is delivered by Content Delivery Networks (CDNs), and, while they optimize QoE metrics such as buffering ratio and start-up time, no single CDN provides optimal performance. In this paper we make the case for elastic CDNs, the ability to build virtual CDNs on-the-fly on top of shared, third-party infrastructure at a scale. To bring this idea closer to reality we begin by large-scale simulations to quantify the effects that elastic CDNs would have if deployed, and build and evaluate MiniCache, a specialized, minimalistic virtualized content cache that runs on the Xen hypervisor. MiniCache is able to serve content at rates of up to 32 Gb/s and handle up to 600K reqs/sec on a single CPU core, as well as boot in about 90 milliseconds on x86 and around 370 milliseconds on ARM32.

Network Function Virtualization is pushing network operators to deploy commodity hardware that will be used to run middlebox functionality and processing on behalf of third parties: in effect, network operators are slowly but surely becoming in-network cloud providers. The market for innetwork clouds is large, ranging from content providers, mobile applications and even end-users.

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.

Traditionally, the number of VMs running on a server and how quickly these can be migrated has been less than optimal mostly because of the memory and CPU requirements imposed on the system by the full-fledged OSes that the VMs run. More recently, work towards VMs based on minimalistic or specialized OSes has started pushing the envelope of how reactive or fluid the cloud can be. In this demo we will demonstrate how to concurrently execute thousands of Xen-based VMs on a single inexpensive server. We will also show instantiation and migraion of such VMs in tens of milliseconds, and transparent, wide area migration of virtualized middleboxes by combining such VMs with the multi-path TCP (MPTCP) protocol.