There are two cruxes of issues identified in differentiated services (diffserv) networks: One is TCP dynamics over Assured Services, and the other is the interaction of TCP and UDP flows for Assured Forwarding Per Hop Behavior (PHB). Therefore, we argue unfair distribution of excess bandwidth in an over-provisioned networks as well as unfair degradation in an underprovisioned network for TCP and UDP flows traffic. First, we consider Two Markers System (TMS) that we have proposed, which is able to properly mark packets and fairly share the bandwidth to each flow for their targeted sending rates. Next, we present simulation results to illustrate the effectiveness of TMS scheme over TCP and UDP interaction. That is, flows in Two Markers System somewhat fairly share the excess bandwidth and experience degradation in proportion to their target rates.