Cloud Network Sharing: Yuefeng Wang (NRG Seminar)

Starts:
11:00 am on Monday, November 4, 2013
Ends:
12:00 pm on Monday, November 4, 2013
Location:
MCS 148
Paper 1: FairCloud: Sharing the Network in Cloud Computing [From SIGCOMM 2012] Author: Lucian Popa, Gautam Kumar, Mosharaf Chowdhury, Arvind Krishnamurthy, Sylvia Ratnasamy and Ion Stoica Abstract: The network, similar to CPU and memory, is a critical and shared resource in the cloud. However, unlike other resources, it is neither shared proportionally to payment, nor do cloud providers offer minimum guarantees on network bandwidth. The reason networks are more difficult to share is because the network allocation of a virtual machine (VM) X depends not only on the VMs running on the same machine with X, but also on the other VMs that X communicates with and the cross-traffic on each link used by X. In this paper, we start from the above requirements–payment proportionality and minimum guarantees and show that the network-specific challenges lead to fundamental tradeoffs when sharing cloud networks. We then propose a set of properties to explicitly express these tradeoffs. Finally, we present three allocation policies that allow us to navigate the tradeoff space. We evaluate their characteristics through simulation and testbed experiments to show that they can provide minimum guarantees and achieve better proportionality than existing solutions. Paper 2: Chatty Tenants and the Cloud Network Sharing Problem [From NSDI 2013] Author: Hitesh Ballani, Keon Jang, Thomas Karagiannis, Changhoon Kim, Dinan Gunawardena and Greg O’Shea Abstract: The emerging ecosystem of cloud applications leads to significant inter-tenant communication across a datacenter’s internal network. This poses new challenges for cloud network sharing. Richer inter-tenant traffic patterns make it hard to offer minimum bandwidth guarantees to tenants. Further, for communication between economically distinct entities, it is not clear whose payment should dictate the network allocation. Motivated by this, we study how a cloud network that carries both intra- and inter-tenant traffic should be shared. We argue for network allocations to be dictated by the least-paying of communication partners. This, when combined with careful VM placement, achieves the complementary goals of providing tenants with minimum bandwidth guarantees while bounding their maximum network impact. Through a prototype deployment and large-scale simulations, we show that minimum bandwidth guarantees, apart from helping tenants achieve predictable performance, also improve overall datacenter throughput. Further, bounding a tenant’s maximum impact mitigates malicious behavior.