IBM's networking broadband services (NBBS) is a unique network control point architecture capable of managing both asynchronous transfer mode (ATM) networks as well as more generic fast packet networks with variable size packets. The NBBS traffic management functions provide value-added enhanced variable bit rate (VBR) services based on statistical traffic descriptors in addition to providing ATM Forum compliant VBR services based on deterministic rule-based traffic descriptors. In this paper, we first summarize NBBS traffic management functions that are relevant to our study. These include traffic estimation, monitoring, policing and dynamic bandwidth adaptation procedures. The NBBS traffic estimation and adaptation module has a novel feature that continuously monitors the source traffic and dynamically adjusts the bandwidth reserved in the network links for the network connection when it detects a significant change in the connection traffic characteristics. The main contribution of this paper is to integrate all these functions in a trace driven simulation experiment to study their aggregate effect in a general network setting using actual traffic traces. Based on observed SNA, TCP, and compressed video traces we observed that NBSS dynamic bandwidth adaptation function provides a three-fold savings in bandwidth use compared to static peak bandwidth allocation in our case study. Our study also provides useful insights into network dimensioning problem in order to achieve a desired level of network availability for different services. Finally, we provide a simple formula for estimating the amount of bandwidth savings achieved through dynamic bandwidth adaptation versus static peak bandwidth allocation in a general network setting by making a comparison on the individual traces in isolation.