 FUNDAMENTAL CONCEPTS IN TRAFFIC MANAGEMENT Modern multiservice networks where Internet Protocol (IP) has ended up the de facto network protocol create a situation that is only going to be exacerbated in the future. Numerous applications that share the common network medium are sometimes radically different in nature and consequently have completely different performance requirements (as dictated by the expectations of users). Because fundamental network resources are finite, an optimal use of these resources is mandated, not only for the sake of efficiency, but also (and more importantly) for the sake of profitability. Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. TRAFFIC MANAGERS TRAFFIC MANAGERS TABLE 15.1 Different Traffic Manager Requirements for Different Applications Applications Capabilities Number of Queues Profiles Support Needed Carrier-class metro Fast forwarding and 1,000-4,000 Small number of and core routers simple behavior aggregated Random Early aggregate (BA)- flows Detection (RED) based classification profiles Multiservice Fast forwarding, and Large number Large number of Fine granularity with switching sophisticated RED profiles Weighted RED classification and (WRED), Early Packet policing/shaping Discard (EPD), and Partial Packet Discard (PPD), both per-class and per-flow behaviors, embedded Segmentation and Reassembly (SAR) for an Asynchronous Transfer Mode (ATM) interface of packet- based networks, and support for frame-relay switching Boundary routers Fast forwarding, and Large number Large number of Fine granularity with at the network sophisticated RED profiles WRED, EPD, and PPD, access point (NAP) classification and both per-class and per- policing/shaping flow behavior, embedded SARing for an ATM interface of packet-based networks and end capabilities for frame-relay and ATM Ethernet and access Less fast forwar