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The Internet is composed of many interconnected, interoperating networks. With the recent advances in Future Internet design, multiple new network architectures, especially Information-Centric Networks (ICN) have emerged. Given the ubiquity of networks based on the Internet Protocol (IP), it is likely that we will have a number of different interconnecting network domains with different architectures, including ICNs. Their interoperability is important, but at the same time difficult to prove. A formal tool can be helpful for such analysis. ICNs have a number of unique characteristics, warranting formal analysis, establishing properties that go beyond, and are different from, what have been used in the state-of-the-art because ICN operates at the level of content names rather than node addresses. We need to focus on node-to-content reachability, rather than node-to-node reachability. In this paper, we present a formal approach to model and analyze information-centric interoperability (ICI). We use Alloy Analyzer’s model finding approach to verify properties expressed as invariants for information-centric services (both pull and push-based models) including content reachability and returnability. We extend our use of Alloy to model counting, to quantitatively analyze failure and mobility properties. We present a formally-verified ICI framework that allows for seamless interoperation among a multitude of network architectures. We also report on the impact of domain types, routing policies, and binding techniques on the probability of content reachability and returnability, under failures and mobility.
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Survivable virtual network mapping with content connectivity against multiple link failures in optical metro networks
Network connectivity, i.e., the reachability of any network node from all other nodes, is often considered as the default network survivability metric against failures. However, in the case of a large-scale disaster disconnecting multiple network components, network connectivity may not be achievable. On the other hand, with the shifting service paradigm towards the cloud in today’s networks, most services can still be provided as long as at least a content replica is available in all disconnected network partitions. As a result, the concept of content connectivity has been introduced as a new network survivability metric under a large-scale disaster. Content connectivity is defined as the reachability of content from every node in a network under a specific failure scenario. In this work, we investigate how to ensure content connectivity in optical metro networks. We derive necessary and sufficient conditions and develop what we believe to be a novel mathematical formulation to map a virtual network over a physical network such that content connectivity for the virtual network is ensured against multiple link failures in the physical network. In our numerical results, obtained under various network settings, we compare the performance of mapping with content connectivity and network connectivity and show that mapping with content connectivity can guarantee higher survivability, lower network bandwidth utilization, and significant improvement of service availability.
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- Award ID(s):
- 1818972
- PAR ID:
- 10177996
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of Optical Communications and Networking
- Volume:
- 12
- Issue:
- 11
- ISSN:
- 1943-0620; JOCNBB
- Format(s):
- Medium: X Size: Article No. 301
- Size(s):
- Article No. 301
- Sponsoring Org:
- National Science Foundation
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