© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Module Summary Cisco IOS software provides a range of QoS tools that address the needs of voice, video, and data applications. Small, medium, and large enterprise QoS solutions encompass classification and marking, congestion avoidance, congestion management, and link- efficiency mechanisms. QoS includes the mechanisms that give network managers the ability to control the mix of bandwidth, delay, variances in delay (jitter), and packet loss in the network.