Figure compares a manual QoS configuration task to an AutoQoS task. A total of 34 lines have been left off the figure so it will fit on the page.

Content 5.1 Introducing Cisco AutoQoS 5.1.2 Cisco AutoQoS Evolution Cisco AutoQoS has evolved into two implementations: Cisco AutoQoS VoIP and Cisco AutoQoS for the Enterprise . Cisco AutoQoS VoIP
Cisco AutoQoS VoIP offers straightforward capabilities to automate VoIP deployments for customers who want to deploy IP telephony but who lack the expertise or staffing to plan and deploy IP QoS and IP services. Cisco AutoQoS VoIP is the first release of Cisco AutoQoS and automates QoS settings for VoIP deployments only. This feature automatically generates interface configurations, policy maps, class maps, and access control lists (ACLs). Cisco AutoQoS VoIP automatically employs Cisco Network-Based Application Recognition (NBAR) to classify voice traffic and mark it with the appropriate differentiated services code point (DSCP) value. You can instruct Cisco AutoQoS VoIP to rely on, or trust, the DSCP markings previously applied to the packets. Cisco AutoQoS for the Enterprise
Cisco AutoQoS for the Enterprise expands its capabilities beyond VoIP and addresses the QoS requirements of enterprise converged networks. Cisco AutoQoS for the Enterprise adds an important step—users can observe the applications discovered during the observation phase (Auto Discovery) and review the QoS policy that Cisco AutoQoS for the Enterprise suggests without deploying that policy. Cisco AutoQoS for the Enterprise blends the design and implementation of QoS, based on the most common enterprise scenarios, into two major steps:

Using NBAR discovery techniques, Cisco AutoQoS automatically discovers which applications the enterprise network uses and generates an optimal policy. This step employs the NBAR discovery mechanism.
Cisco AutoQoS then implements the generated policy.

Figure shows the hardware and software requirements for Cisco AutoQoS.

Content 5.1 Introducing Cisco AutoQoS 5.1.3 Deploying Cisco AutoQoS on Switches Deploying Cisco AutoQoS VoIP on Switches
There are various LAN commands, depending on the platform and operating system (Cisco IOS software versus Cisco Catalyst operating system software). For the Cisco IOS software-based Catalyst 2960 and Catalyst 3560 Series switches, there are two Cisco AutoQoS configuration commands: One command is for IP phone connections, and the other is for trusted connections to other network devices. However, a single command is enough to enable Cisco AutoQoS VoIP. Cisco AutoQoS VoIP in the LAN fulfills these QoS requirements:

A single command enables Cisco AutoQoS VoIP in a LAN, and another command provides support for Cisco IP Phone and Cisco IP Communicator equipment.
Cisco AutoQoS automatically configures QoS parameters for optimal voice performance based upon Cisco best-practice recommendations, extensive lab testing, and input from a broad base of Cisco Unified Communications customer installations.
Cisco AutoQoS VoIP determines trust and extended trust boundary settings automatically. A user can bypass the IP phone and connect a PC directly to a switch, but trust is disabled when you remove the IP phone.
Cisco AutoQoS VoIP configures class of service (CoS) to DSCP (to egress queue) mapping.
Cisco AutoQoS VoIP determines optimal priority queuing (PQ) and weighted round robin (WRR) configuration settings for static, dynamic-access, voice VLAN (VVLAN), and trunk ports.

To configure the QoS settings and the trusted boundary feature for Cisco IP phones, you must enable CDP version 2 or later on the switch port, where the IP phone is connected. If you enable the trusted boundary feature, a syslog displays a warning message if CDP is not enabled or if CDP is running version 1. You need to enable CDP only for the Cisco IP phone QoS configuration; CDP does not affect the other components of the automatic QoS features. Figure summarizes these points. Configuring Cisco AutoQoS on Cisco Catalyst Switches
For Cisco IOS-based Catalyst switches, there are two Cisco AutoQoS VoIP configuration commands. Figure shows the command syntax. One command is for trusted connections to other network devices, and the other is for Cisco IP phone connections:

The auto qos voip trust interface configuration command activates Cisco AutoQoS VoIP on a Cisco IOS-based switch and sets the ingress interface to trust the ingress CoS QoS marking received in the packet. It also reconfigures the egress queues on the interface.
The auto qos voip cisco-phone interface configuration command enables the trusted boundary feature. The trusted boundary feature uses the CDP to detect the presence or absence of a Cisco IP phone. When AutoQoS detects a Cisco IP phone, the ingress classification on the interface is set to trust the QoS label received in the packet. When a Cisco IP phone is absent, AutoQoS sets the ingress classification to not trust the QoS label in the packet. It also reconfigures the egress queues on the interface. This command extends the trust boundary if an IP phone is detected.

Do not use these commands if there are previous QoS configurations on the switch. However, you can tune the generated Cisco AutoQoS configuration parameters (Cisco AutoQoS template) after using these commands. Note
Both commands, in the same format, also apply to Cisco Catalyst 4500 Series Switches. As with Cisco Catalyst 2960 (EI) and 3560 Switches, Cisco Catalyst 4500 Series Switches do not support the Cisco SoftPhone option. When Cisco AutoQoS VoIP is enabled on the first interface, QoS is globally enabled (mls qos global configuration command). Example: Cisco AutoQoS VoIP Switch Configuration
The example in Figure shows how to enable Cisco AutoQoS VoIP to trust the QoS marking received in incoming packets when the switch is connected to the trusted device (router) using the Fast Ethernet interface 0/24. The example also shows how to enable Cisco AutoQoS VoIP to trust the QoS marking received in incoming packets when the device connected to Fast Ethernet interface 0/11 is detected and is a Cisco IP phone.

Content 5.1 Introducing Cisco AutoQoS 5.1.4 Cisco AutoQoS for the Enterprise: Router Deployment Restrictions General Restrictions
The VoIP feature is supported on the following interfaces, data-link connection identifiers (DLCIs), and permanent virtual circuits (PVCs) only:

Serial interfaces with Point-to-Point Protocol (PPP) or High-Level Data Link Control (HDLC)
Frame Relay (point-to-point subinterfaces only)
Low-speed and high-speed ATM PVCs in point-to-point subinterfaces
Frame Relay-to-ATM Interworking links

Note
Synchronous serial interfaces are classified as low speed if the bandwidth is less than or equal to 768 kbps. A synchronous serial interface is classified as high speed if its bandwidth is greater than 768 kbps. This classification is also true for ATM PVCs. Figure summarizes these restrictions. Serial Interface Restrictions
For a serial interface with a low-speed link, Multilink PPP (MLP) is configured automatically. The serial interface must have an IP address. When you configure MLP, this IP address is removed and put on the MLP bundle. You must meet these conditions to ensure that the traffic goes through the low-speed link:

You must have Cisco AutoQoS for the Enterprise configured at the both ends of the link.
The amount of bandwidth configured must be the same on both ends of the link.

Frame Relay DLCI Restrictions
Cisco AutoQoS has the following restrictions in Frame Relay environment:

You cannot configure Cisco AutoQoS on a Frame Relay DLCI if a map class is attached to the DLCI.
If a Frame Relay DLCI is already assigned to one subinterface, you cannot configure