How to provide quality of service (QoS) guarantees in routing and switching systems has become one of the key research topics in the areas of routing and switching technologies. Differentiated services architecture (DiffServ) is known as a promising way for supporting QoS in a high-speed backbone network scenario. However, the measurement indexes for realtime multimedia traffic, which plays very important roles in next generation internet, are not so clearly defined. In this paper, a new service architecture called SOQG (Service Orient QoS Guarantees) aiming at providing QoS guarantees for multimedia traffic is first proposed. SOQG classifies the internet traffic into five classes: EF, JCC, BCG-H, BCG-L and BE. Then, Based on this architecture, we propose a new switch called load balanced differentiated universal service support switch (LBDU). LBDU consists of three modules: BCU (Bandwidth Control Unit), LBS (Load Balanced Scheduling) and XOS ( Cross-point Output Scheduling). We evaluate LBDU by comprehensive simulations. As expected, LBDU can provide delay and bandwidth guarantees for both EF and JCC traffic.