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Addressing Issues of Cloud Resilience, Security and Performance through Simple Detection of Co-locating Sibling Virtual Machine Instances

Most current Infrastructure Clouds are built on shared tenancy architectures, with resources shared amongst 
large numbers of customers. However, multi tenancy can lead to performance issues (so-called “noisy 
neighbours”) and also brings potential for serious security breaches such as hypervisor breakouts. 
Consequently, there has been a focus in the literature on identifying co-locating instances that are being 
affected by noisy neighbours or suggesting that such instances are vulnerable to attack. However, there is 
limited evidence of any such attacks in the wild. More beneficially, knowing that there is co-location 
amongst your own Virtual Machine instances (siblings) can help to avoid being your own worst enemy: 
avoiding your instances acting as your own noisy neighbours, building resilience through ensuring hostbased 
redundancy, and/or reducing exposure to a single compromised host. In this paper, we propose and 
demonstrate a test to detect co-locating sibling instances on Xen-based Clouds, as could help address such 
needs, and evaluate its efficacy on Amazon’s EC2.