This document defines a limited common set of Diffserv PHBs and codepoints (DSCPs) to be applied at (inter)connections of two separately administered and operated networks, and explains how this approach can simplify network configuration and operation. Many network providers operate MPLS using Treatment Aggregates for traffic marked with different Diffserv Per Hop Behaviors, and use MPLS for interconnection with other networks. This document offers a simple interconnection approach that may simplify operation of Diffserv for network interconnection among providers that use MPLS and apply the Short-Pipe tunnel mode. While motivated by the requirements of MPLS network operators that use Short-Pipe tunnels, this document is applicable to other networks, both MPLS and non-MPLS.