Hello, The NSI group has also been studying the G.800 terminology, and has attempted to make a table with the different terms in NSI, G.800 and NML. NSI G.800 NML --- ----- --- Layer Topology Layer Network N/A[1] Subnetwork Subnetwork Network/SwitchMatrix[2] Link Link Link[3] Port Link Point Port Forwarding Port Forwarding Point Port Segment Link connection Link Subnet connection Segment Access Port Access Group Port?[4] [1]: The Layer topology concept is not something that we describe explicitly. Nor do I think that we really need a name for it. It describes a group of nodes on the same layer. We can describe nodes, and are planning to describe what layer nodes are on. Getting this group of nodes is then just a simple query. [2]: A Subnetwork in G.800 terminology is the place where the switching occurs. However, the subnetwork concept is used at different abstraction levels, and we have not decided yet how to represent different abstraction levels. [3]: The Link concept is still somewhat vague. G.800 uses the term Link to describe a connection between two ports (G.800: points). However, they also describe a concept of multiplexing using forwarding ports, creating a bundle of links on the client layer, this bundle is not explicitly named in G.800. I'm not entirely sure whether NSI Link concept is the NML Link concept, or the G.800 bundle (or both). [4]: Access Port is the point at which a client connects to the network. In my mind NML does not need to make a special distinction for this, and we can just call it a Port. Jeroen.