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In this work, we consider the network slice composition problem for Service Function Chains (SFCs), which addresses the issue of allocating bandwidth and VNF resources in a way that guarantees the availability of the SFC while minimizing cost. For the purpose of satisfying the availability requirement of the SFC, we adapt a traffic-weighted availability model which ensures that the long-term fraction of traffic supported by the slice topology remains above a desired threshold. We propose a method for composing a single or multi-path slice topology and for properly dimensioning VNF replicas and bandwidth on the slice paths. Through simulations, we show that our proposed algorithm can reduce the total cost of establishment compared to a dedicated protection approach in 5G networks.
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Availability-guaranteed slice composition for service function chains in 5G transport networks
Availability is a key service metric when deploying service function chains (SFCs) over network slices in 5G networks. We study the problem of determining the composition of a slice for a service function chain and the mapping of the slice to the physical transport network in a way that guarantees availability of the SFC while minimizing cost. To improve the availability, we design a slice that provides multiple paths (possibly with non-disjoint routing over the physical infrastructure) for hosting SFCs, and we determine the appropriate dimensioning of bandwidth on each path. Our simulation results show the effectiveness of our approach in terms of the cost of establishing the SFC and the SFC acceptance ratio.
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- Award ID(s):
- 2008856
- PAR ID:
- 10209156
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of Optical Communications and Networking
- Volume:
- 13
- Issue:
- 3
- ISSN:
- 1943-0620; JOCNBB
- Format(s):
- Medium: X Size: Article No. 14
- Size(s):
- Article No. 14
- Sponsoring Org:
- National Science Foundation
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