Orange Juniper Telefonica Nokia Huawei Technologies Delivery of network services assumes that appropriate setup is provisioned over the links that connect customer termination points and a provider network. The required setup to allow successful data exchange over these links is referred to as an attachment circuit (AC), while the underlying link is referred to as "bearer". This document specifies a YANG service data model for ACs. This model can be used for the provisioning of ACs before or during service provisioning (e.g., Network Slice Service). The document also specifies a YANG service model for managing bearers over which ACs are established.