Abstract--In heterogeneous networks such as today's Internet, the differentiated services architecture promises to provide QoS guarantees through scalable service differentiation. Traffic marking is an important component of this framework. In this paper, we propose two new aggregate markers that are stateless, scalable and fair. We leverage stateless Active Queue Management (AQM) algorithms to enable fair and efficient token distribution among individual flows of an aggregate. The first marker, Probabilistic Aggregate Marker (PAM), uses the Token Bucket burst size to probabilistically mark incoming packets to ensure TCP-friendly and proportionally fair marking. The second marker, Stateless Aggregate Fair Marker (F-SAM) approximates fair queueing techniques to isolate flows while marking packets of the aggregate. It distributes tokens evenly among the flows without maintaining per-flow state. Our simulation results show that our marking strategies show upto 30% improvement over ot...