With the advent of high speed networks, the future communication environment is expected to comprise a variety of networks with widely varying characteristics. The next generation multimedia applications require transfer of a wide variety of data such as voice, video, graphics, and text which have widely varying access patterns such as interactive, bulk transfer, and real-time guarantees. Traditional protocol architectures have difficulty in supporting multimedia applications and high-speed networks because they are neither designed nor implemented for such a diverse communication environment. In this paper, we analyze the drawbacks of traditional protocol architectures and propose two alternative architectures for the next generation high-speed network environment: Direct Application Association and Integrated Layered Logical Multiplexing. We implement sample protocol stacks for each of the above models using the most widely used protocol stack (TCP/UDP-IP-Ethernet) in the context of the x-kernel. The performance of these protocol architectures is shown to be comparable to that of a traditional protocol architecture. They win by enabling the key requirements (Application specific Quality of Service) and optimizations (Integrated Layer Processing) necessary for future communication environments.