In this paper, we propose an approach to flow-unaware admission control, which is combination with an aggregate packet-forwarding scheme, improves scalability of networks while guaranteeing end-to-end deadlines for real-time applications.We achieve this by using an off-line delay computation and verification step, which allows to reduce the overhead at admission control while keeping admission probability and resources utilization high.Our evaluation data show our system's admission probabilities are very close to those of significantly more expensive flow-aware approaches. At the same time, admission control overhead during flow establishment is very low. Our results therefore support the claim from the DS architecture literature that scalability can be achieved through flow aggregation without sacrificing resource utilization and with significant reduction in run time overhead.