Transmission and Multiplexing (TM); Generic requirements of transport functionality of equipment; Part 4-1: Synchronous Digital Hierarchy (SDH) path layer functions
The present document specifies a library of basic building blocks and a set of rules by which they are combined in order to describe transport functionality of equipment. The library comprises the functional building blocks needed to completely specify the generic functional structure of the European Transmission Hierarchies. Equipment which is compliant with the present document shall be describable as an interconnection of a subset of these functional blocks contained within the present document. The interconnections of these blocks shall obey the combination rules given. The generic functionality is described in EN 300 417-1-1 [6].