6th European Conference - Academic Conferences

Marco Carvalho et al.
systems starts to become reality, as new adopters begin to leverage the capabilities of these
combined technologies for high-end systems development.
Following several industry initiatives, the United States (US) Government begins to consider the new
landscape. For example the Central Intelligence Agency (CIA) has recently reported it is investing in
cloud analytics, cloud widgets and services, cloud security-as-a-service, cloud enterprise data
management and cloud infrastructure, using commercial IT technologies to analyze multi-lingual data,
audio, Twitter tweets, video and text messages that add layers of complexity to intelligence gathering
(Yasin, 2010).
When properly managed and coordinated, the new environment provides the means and tools for
large-scale distributed systems development, including on-demand resource allocation, dynamic
resource management, diversity in services and capabilities, intrinsic replication for data recovery and
several other capabilities. The challenge, however, is to coordinate all these powerful features in
order to enable resilient mission-critical systems.
In this paper we introduce an organic approach to mission resilience in large-scale and adaptive
computational environments. In particular, we focus on the issues of mission continuity and
survivability in response to attacks, as well as runtime system management and adaptation. In section
2 we briefly discuss the proposed challenges and requirements of mission critical systems for SOA
and cloud environments, as well as some background discussions on service discovery and
orchestration. In section 3 we introduce our biologically-inspired approach on organic resilience for
mission-critical systems, followed by some preliminary discussions on the proposed ideas, and
conclusions.
2. Mission critical systems in the cloud
As previously defined, the goal of resilient mission critical systems is to ensure the successful
execution and completion of the mission while remaining mission-capable in response to localized
failures and attacks. In the context of this work we are primarily concerned with the availability and
integrity aspects of the problem. While data exfiltration and privacy are important and challenging
issues in the cloud environments, they are not considered in the scope of this work. We are primarily
concerned with attacks or failures that may directly disrupt the mission. While there are multiple ways
to describe and represent a mission we will consider that a mission can be represented as a set of
workflows, or a set of strictly ordered sequences of tasks, as illustrated in Figure 1.
In this example, a mission is composed as a set of workflows. Each workflow is composed by a set of
ordered tasks and may represent, for instance, a set of image processing steps to be performed on
imagery collected by surveillance aerial vehicles. Each processing step, represented by the task (A,
F, G, and A) must be performed in strict order, and services 1, 4 and 7 have been tasked to jointly
execute the workflow. It is important to note that service selection in this example may refer to the
orchestration of services provided by a supporting Service Oriented Architecture (SOA) in the cloud.
Figure 1: Distributed execution of a mission represented as a set of workflows
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