Experiences With Modeling Network Topologies At Multiple Levels Of Abstraction

Network management is becoming increasingly automated, and automation depends on detailed, explicit representations of data about the state of a network and about an operator's intent for its networks. In particular, we must explicitly represent the desired and actual topology of a network. Almost all other network-management data either derives from its topology, constrains how to use a topology, or associates resources (e.g., addresses) with specific places in a topology.MALT, a Multi-Abstraction-Layer Topology representation, supports virtually all network management phases: design, deployment, configuration, operation, measurement, and analysis. MALT provides interoperability across our network-management software, and its support for abstraction allows us to explicitly tie low-level network elements to high-level design intent. MALT supports a declarative style, simplifying what-if analysis and testbed support.We also describe the software base that supports efficient use of MALT, as well as numerous, sometimes painful lessons we have learned about curating the taxonomy for a comprehensive, and evolving, representation for topology.