Merlin: A Language for Provisioning Network Resources

This paper presents Merlin, a new framework for managing resources in software-defined networks. With Merlin, administrators express high-level policies using programs in a declarative language. The language includes logical predicates to identify sets of packets, regular expressions to encode forwarding paths, and arithmetic formulas to specify bandwidth constraints. The Merlin compiler uses a combination of advanced techniques to translate these policies into code that can be executed on network elements including a constraint solver that allocates bandwidth using parameterizable heuristics. To facilitate dynamic adaptation, Merlin provides mechanisms for delegating control of sub-policies and for verifying that modifications made to sub-policies do not violate global constraints. Experiments demonstrate the expressiveness and scalability of Merlin on real-world topologies and applications. Overall, Merlin simplifies network administration by providing high-level abstractions for specifying network policies and scalable infrastructure for enforcing them

Scalable Network Management with Merlin

This paper presents the Merlin network management framework. With Merlin, network administrators express functionality such as accounting, bandwidth provisioning, and traffic filtering in a high-level policy language, and use automated tools and mechanisms to implement them. The framework includes: (i) a declarative language for specifying policies, (ii) infrastructure for distributing, refining, and coordinating enforcement of policies, and (iii) a run-time monitor that inspects incoming and outgoing traffic on end hosts. We describe Merlin's policy language and enforcement infrastructure, illustrate the use of Merlin on case studies, and present experimental results demonstrating that Merlin is more efficient and scalable than equivalent implementations based on programmable switches and centralized middleboxes. Overall, Merlin simplifies the task of network administration by providing high-level abstractions and tools for specifying and enforcing rich network policies