In this paper we propose a new model for providing QoS guarantees to real time multimedia applications in mobile ad hoc networks. Our model assures equal delay for each packet at every hop in the path, and handles network congestion through the use of call admission control and congestion control mechanisms. The effectiveness of our proposed solution in meeting desired QoS differentiation at a specific node and from end-to-end are assessed by simulation using a queueing network model implemented in QNAP. The experiments results show that our proposed solution provides consistent proportional differentiation for any service class and validates our claim even under bursty traffic and fading channel conditions.