1 research outputs found
Research on Survivability Strategies of Virtual Network
Virtualization facilitates heterogeneous cloud applications to share the same
physical infrastructure with admirable flexibility, while resource efficiency
and survivability are critical concerns for virtual network embedding (VNE). As
more and more internet applications migrate to the cloud, the resource
efficiency and the survivability of VNs, such as single link failure or
large-scale disaster survivability, have become crucial issues. Separating the
VNE problem into node and link mapping sub-problems without coordination might
cause a high embedding cost. This dissertation presents two independent
approaches to solve the aforementioned challenges. First, we study two-stage
coordinated survivable VNE (SVNE) problem and propose an adaptive path
splitting based SVNE (APSS) scheme. We first develop a concise anchor node
strategy to restrict the solution space of the candidate substrate nodes, which
coordinates node mapping with link mapping to limit the distance spans of the
virtual links. Then, we employ an adaptive path splitting policy to provide
full protection against single-link failures with partial backup resource, and
design an agile frequency slot windows choosing mechanism to mitigate the
spectrum fragmentation for link resource efficiency. Simulation results
demonstrate that the proposed APSS scheme can achieve satisfactory performance
in terms of spectrum utilization and blocking ratio. Second, we propose a
synchronous evacuation strategy for VNs with dual virtual machines (VMs) inside
a disaster risk zone (DRZ), which suffer higher risks than the VNs with single.
The evacuation strategy exploits post-copy technique to sustain the online
service alive and enhances synchronous VM migrations to shorten the dual-VM
evacuation time. Numerical results show that the proposed strategy can
outperform the best-effort scheme in terms of average and total evacuation
times of dual-VMs.Comment: Master Degree Thesis at Chongqing University of Posts and
Telecommunication