Step 1: The Class Map
The first step for configuring any QoS mechanism in the MQC is the configuration of a class-map.
Simply stated, the class map defines which traffic you want the router to match. This is the fundamental step that allows the router to differentiate one traffic type from another. This is traffic classification, and [...]

The Catalyst 5000 Family of switches requires CatOS software version 5.1(1) or higher for QoS feature support. The Catalyst 5000 Family of switches runs CatOS software up to CatOS software version 6.4. The Catalyst 5000 Family of switches does not support Native IOS software or the CatOS software version 7 train.
MLS changes the behavior of [...]

Catalyst 4000 CatOS switches provide for QoS classification and congestion management solely based on CoS values. The Catalyst 4000 IOS switches, discussed  CCIE R&S, support a wider range of QoS. For the Catalyst 4000 CatOS switches, a high- and low-priority transmit port queue with round-robin scheduling accomplish congestion management. The Catalyst 4000 CatOS switches do [...]

As established in the previous section, subnet bits cannot be all zeros or all ones in classful environments. Likewise, an IPv4 host address cannot have all its host bits set to zerothis setting is reserved for the address that routers use to represent the network or subnet itself. And the host bits cannot be set [...]

The  expedited forwarding (EF) PHB is designed to build a low-loss, low-latency, and low-jitter, assured bandwidth class. If all of those characteristics sound a bit like how you would want to treat VoIP traffic, you are already well on your way to understanding the purpose of this PHB.
Although RFC 2598 does not specifically say that [...]

Subnet Bandwidth Manager (SBM), defined by RFC 2814, is a signaling protocol that deals with RSVP-based admission control on 802-based networks. Today, SBM is primarily used in switched Ethernet environments for LAN-based admission control for RSVP flows. Simply stated, SBM is responsible for handling admission control for resource reservations.
On each managed segment, an election process [...]

The conventions used to present command syntax in this book are the same conventions used in the IOS Command
Reference. The Command Reference describes these conventions as follows:
•Vertical bars (|) separate alternative, mutually exclusive elements.
• Square brackets ([ ]) indicate optional elements.
• Braces ( ) indicate a required choice.
• Braces within brackets ( ) indicate a [...]

The problems of tail drop and global synchronization can both be addressed with congestion avoidance. Congestion avoidance is sometimes called active queue management, or Random Early Detection (RED). The Introduction section of RFC 2309 defines the need for active queue management as follows:
The traditional technique for managing router queue lengths is to set a maximum [...]