network control

As with all network control papers, the QoS Design Guide needed to be updated and expanded after a couple years. During this time, customers increasingly were struggling with how best to deploy QoS for videoconferencing and different types of data applications. Therefore, the scope of the original design guide was expanded to include these applications, and a second version of the document was released in August 2002. At the time, all design guides originating from the solutions engineering team were rebadged as Solution Reference Network Designs (SRNDs), to set them apart from the many (often unverified and not scale-tested) design guides available on Cisco.com. Thus, the second version of this document was titled the Enterprise QoS SRND

Shortly thereafter, the QoS Baseline was completed and released internally. Because the QoS Baseline conflicted with some of the (DSCP marking) recommendations published in the QoS SRND, it took precedence and required the Enterprise QoS SRND to be rewritten to be compliant with the QoS Baseline. This caused changes in the document because the marking recommendations put forward in the Enterprise QoS SRND reflected the best practices for an enterprise, but not necessarily for a service provider. As the lines between enterprise and service provider are not only blurring but also requiring a level of cooperation previously unprecedented (as discussed in additional detail in Chapter 15, "MPLS VPN QoS Design"), it is important for a single set of marking recommendations to be used for both enterprise and service provider network control guides