Network quality of service for the enterprise: A broad overview

One of the biggest challenges facing the Internet today is to scale to an infrastructure that can provide quality-of-service (QoS) to a wide variety of applications and traffic types. As the Internet continues to grow at a rapid pace and new applications emerge, the task of managing bandwidth becomes more important. This implies that the traditional "best-effort" service that is provided by TCP/IP is no longer sufficient in many cases. The concept of QoS has evolved to meet the increasing need for bandwidth management. This paper provides an overview of what QoS is why we need it, and what the current approaches for implementing it are. The paper also compares some existing vendor products in the QoS space and finally provides insights into some of the vexing problems that still remain difficult to solve for QoS designers.