Huawei Technologies Futurewei Huawei Technologies Cisco Huawei Technologies A transport network is a server-layer network to provide connectivity services to its client. The topology and tunnel information in the transport layer has already been defined by generic Traffic- engineered models and technology-specific models (e.g., OTN, WSON). However, how the client signals are accessing to the network has not been described. These information is necessary to both client and provider. This draft describes how the client signals are carried over transport network and defines YANG data models which are required during configuration procedure. More specifically, several client signal (of transport network) models including ETH, STM-n, FC and so on, are defined in this draft.