End-to-end QoS deployment techniques for Cisco Catalyst series switches
Examine various QoS components, including congestion management, congestion
avoidance, shaping, policing/admission control, signaling, link efficiency mechanisms, and classification and marking
Map specified class of service (CoS) values to various queues and maintain CoS values through the use of 802.1q tagging on the Cisco Catalyst 2900XL, 3500XL and Catalyst 4000 and 2948G/2980G CatOS Family of Switches
Learn about classification and rewrite capabilities and queue scheduling on the Cisco Catalyst 5000
Implement ACLs, ACPs, ACEs, and low-latency queuing on the Cisco Catalyst 2950 and 3550 Family of Switches
Understand classification, policying, and scheduling capabilities of the Catalyst 4000 and 4500 IOS Family of Switches
Configure QoS in both Hybrid and Native mode on the Catalyst 6500 Family of Switches Utilize Layer 3 QoS to classify varying levels of service with the Catalyst 6500 MSFC and Flexwan
Understand how to apply QoS in campus network designs by examining end-to-end case studies
Quality of service (QoS) is the set of techniques designed to manage network resources. QoS refers to the capability of a network to provide better service to selected network traffic over various LAN and WAN technologies. The primary goal of QoS is to provide flow priority, including dedicated bandwidth, controlled jitter and latency (required by some interactive and delay-sensitive traffic), and improved loss characteristics.
While QoS has become an essential technology for those organizations rolling out a new
Each Cisco IP Phone port has four queues comprised of a single threshold statically configured at 100 percent, 4q1t. Queue 0 functions as a high-priority queue for traffic with a CoS value of 5.
Spanning-tree bridge protocol data units (BPDUs) also use this queue. Voice traffic from the internal IP Phone appliance has a CoS value of 5 by default. All queues are serviced in a round-robin fashion. However, a timer maintains queue priority by limiting service to the low-priority queues when there is traffic in the high-priority queue. Subsequently, the Cisco IP Phone itself manages input and output scheduling for traffic traversing the integrated switch ports.
Voice VLANs and Extended Trust
Through the use of dot1q trunks, voice traffic from an IP Phone connected to an access port can reside on a separate VLAN and subnet. The workstation attached to the IP Phone might still reside on the access, or native, VLAN. This additional VLAN on an access port for voice traffic is referred to as a voice VLAN in Cisco IOS Software and auxiliary VLAN in CatOS. Subsequently, with the use of voice VLANs, all voice traffic is tagged to and from the Cisco IP Phone and
Catalyst switch. The Catalyst switches use Cisco Discovery Protocol (CDP) to inform the IP Phone of the voice VLAN ID. By default, Cisco IP Phone voice traffic has a CoS value of 5. Figure 2-9 provides an example logical depiction of a voice VLAN. A common network design is to deploy both voice VLANs with trusting configurations for Cisco IP telephony applications (such as Cisco IP Phones).
Figure 2-9. Example Logical Depiction of Voice VLAN
Another QoS option for IP Phones is extended trust. The switch can inform the IP Phone via CDP whether to trust ingress frames on its P1 port. The IP Phone may also be informed to overwrite the CoS value of the ingress frames on the P1 port with a specific CoS value. By default, the IP Phone does not trust frames arriving on the P1 port and rewrites the CoS value to 0 of any tagged frames. Untagged frames do not have CoS value.
Extended trust is a feature available to any device that can interpret the CDP fields describing the voice VLAN information. At the time of publication, Cisco IP Phones and other Cisco appliances are the only devices to use this feature.
Figure 2-10. Catalyst Extended Trust Concept
• Table of Contents
• Index
Cisco Catalyst QoS: Quality of Service in Campus Networks By Mike Flannagan CCIE® No. 7651, Richard Froom CCIE No. 5102, Kevin Turek CCIE No. 7284
Publisher: Cisco Press Pub Date: June 06, 2003
ISBN: 1-58705-120-6 Pages: 432
End-to-end QoS deployment techniques for Cisco Catalyst series switches
Examine various QoS components, including congestion management, congestion
avoidance, shaping, policing/admission control, signaling, link efficiency mechanisms, and classification and marking
Map specified class of service (CoS) values to various queues and maintain CoS values through the use of 802.1q tagging on the Cisco Catalyst 2900XL, 3500XL and Catalyst 4000 and 2948G/2980G CatOS Family of Switches
Learn about classification and rewrite capabilities and queue scheduling on the Cisco Catalyst 5000
Implement ACLs, ACPs, ACEs, and low-latency queuing on the Cisco Catalyst 2950 and 3550 Family of Switches
Understand classification, policying, and scheduling capabilities of the Catalyst 4000 and 4500 IOS Family of Switches
Configure QoS in both Hybrid and Native mode on the Catalyst 6500 Family of Switches Utilize Layer 3 QoS to classify varying levels of service with the Catalyst 6500 MSFC and Flexwan
Understand how to apply QoS in campus network designs by examining end-to-end case studies
Quality of service (QoS) is the set of techniques designed to manage network resources. QoS refers to the capability of a network to provide better service to selected network traffic over various LAN and WAN technologies. The primary goal of QoS is to provide flow priority, including dedicated bandwidth, controlled jitter and latency (required by some interactive and delay-sensitive traffic), and improved loss characteristics.
While QoS has become an essential technology for those organizations rolling out a new
• Table of Contents
• Index
Cisco Catalyst QoS: Quality of Service in Campus Networks By Mike Flannagan CCIE® No. 7651, Richard Froom CCIE No. 5102, Kevin Turek CCIE No. 7284
Publisher: Cisco Press Pub Date: June 06, 2003
ISBN: 1-58705-120-6 Pages: 432
End-to-end QoS deployment techniques for Cisco Catalyst series switches
Examine various QoS components, including congestion management, congestion
avoidance, shaping, policing/admission control, signaling, link efficiency mechanisms, and classification and marking
Map specified class of service (CoS) values to various queues and maintain CoS values through the use of 802.1q tagging on the Cisco Catalyst 2900XL, 3500XL and Catalyst 4000 and 2948G/2980G CatOS Family of Switches
Learn about classification and rewrite capabilities and queue scheduling on the Cisco Catalyst 5000
Implement ACLs, ACPs, ACEs, and low-latency queuing on the Cisco Catalyst 2950 and 3550 Family of Switches
Understand classification, policying, and scheduling capabilities of the Catalyst 4000 and 4500 IOS Family of Switches
Configure QoS in both Hybrid and Native mode on the Catalyst 6500 Family of Switches Utilize Layer 3 QoS to classify varying levels of service with the Catalyst 6500 MSFC and Flexwan
Understand how to apply QoS in campus network designs by examining end-to-end case studies
Quality of service (QoS) is the set of techniques designed to manage network resources. QoS refers to the capability of a network to provide better service to selected network traffic over various LAN and WAN technologies. The primary goal of QoS is to provide flow priority, including dedicated bandwidth, controlled jitter and latency (required by some interactive and delay-sensitive traffic), and improved loss characteristics.
While QoS has become an essential technology for those organizations rolling out a new
Summary
This chapter has given you a broad view of the QoS theories and mechanisms at Layer 2 and Layer 3, but hopefully left you hungry for more details. Those details are coming in each of the remaining chapters of this book. Now that you are familiar with the RFCs and overall concepts that drive the development of QoS mechanisms on Cisco devices, you will read about the very specific and often intricate details of these mechanisms on Cisco Catalyst platforms. You may find, as you read through some of the more detailed chapters, that you want to refer back to this chapter to see where a specific implementation detail fits into the end-to-end QoS strategy.
The next chapter includes a broad overview of QoS feature support on all Catalyst switches, and then focuses on QoS specifics on the Catalyst 2900XL, 3500XL, and 4000 CatOS Family of switches.
As you read the implementation specifics in the following chapters, keep an eye on the big picture of end-to-end QoS. From the Catalyst 3550 Family of switches to the Catalyst 4000 IOS Family of switches to the Catalyst 6500 Family of switches, think about how the configuration of each platform can be customized to fit the exact needs of your network. After all, you want to build a custom QoS policy that allows for the use of all the platforms in a single network, with a single end-to-end policy.
• Table of Contents
• Index
Cisco Catalyst QoS: Quality of Service in Campus Networks By Mike Flannagan CCIE® No. 7651, Richard Froom CCIE No. 5102, Kevin Turek CCIE No. 7284
Publisher: Cisco Press Pub Date: June 06, 2003
ISBN: 1-58705-120-6 Pages: 432
End-to-end QoS deployment techniques for Cisco Catalyst series switches
Examine various QoS components, including congestion management, congestion
avoidance, shaping, policing/admission control, signaling, link efficiency mechanisms, and classification and marking
Map specified class of service (CoS) values to various queues and maintain CoS values through the use of 802.1q tagging on the Cisco Catalyst 2900XL, 3500XL and Catalyst 4000 and 2948G/2980G CatOS Family of Switches
Learn about classification and rewrite capabilities and queue scheduling on the Cisco Catalyst 5000
Implement ACLs, ACPs, ACEs, and low-latency queuing on the Cisco Catalyst 2950 and 3550 Family of Switches
Understand classification, policying, and scheduling capabilities of the Catalyst 4000 and 4500 IOS Family of Switches
Configure QoS in both Hybrid and Native mode on the Catalyst 6500 Family of Switches Utilize Layer 3 QoS to classify varying levels of service with the Catalyst 6500 MSFC and Flexwan
Understand how to apply QoS in campus network designs by examining end-to-end case studies
Quality of service (QoS) is the set of techniques designed to manage network resources. QoS refers to the capability of a network to provide better service to selected network traffic over various LAN and WAN technologies. The primary goal of QoS is to provide flow priority, including dedicated bandwidth, controlled jitter and latency (required by some interactive and delay-sensitive traffic), and improved loss characteristics.
While QoS has become an essential technology for those organizations rolling out a new
Chapter 3. Overview of QoS Support on Catalyst Platforms and Exploring QoS on the Catalyst 2900XL, 3500XL, and Catalyst 4000 CatOS Family of Switches
Previous chapters described the necessity for QoS in campus networks and the fundamentals behind QoS operation. This chapter explains the various platform QoS features available across the Cisco Catalyst product family. A group of concise tables in the beginning of this chapter provides a quick reference for QoS features available for each Catalyst platform. In addition, this chapter, along with subsequent chapters, begins the product tour of the access layer Catalyst switches with the fewest QoS features and continues with the high-end core Catalyst switches with industry-leading QoS features. Although the access layer switches support only a few QoS features, these switches provide an excellent foundation for exploring QoS fundamentals in the campus network.
Specifically, this chapter covers the following topics:
Brief Per–Catalyst Platform QoS Features Table QoS Features Overview
QoS Features on the Catalyst 2900XL and 3500XL Switches QoS Features on the Catalyst 4000 CatOS Switches
The Cisco Catalyst 2900XL, 3500XL, and 4000 Family of switches share Layer 2 QoS features needed on access layer switches. These features include the following:
Classification Marking
Congestion Management
This chapter covers these topics on the respective platforms with command references,
examples, and case studies. Upon completion of this chapter, you will understand each Catalyst platform's supported QoS features and be able to configure the Catalyst 2900XL, 500XL, and 4000 CatOS Family of switches for packet classification, marking, and congestion management.
From a platform perspective, the Catalyst 4000 CatOS Family of switches must be distinguished from the Catalyst 4000 Cisco IOS Family of switches due to individual differences in QoS features and configuration. The supervisor engine model determines whether a Catalyst 4000 switch operates on CatOS or Cisco IOS. In addition, the Catalyst 4000 Layer 3 services module also has exclusive Layer 3 QoS features (discussed in Chapter 7, "Advanced QoS Features Available on the Catalyst 4000 IOS Family of Switches and the Catalyst G-L3 Family of Switches"). This chapter is only applicable to the Catalyst 4000 CatOS switches. Table 3-8 shows which Catalyst 4000 switches are applicable to this chapter.
• Table of Contents
• Index
Cisco Catalyst QoS: Quality of Service in Campus Networks By Mike Flannagan CCIE® No. 7651, Richard Froom CCIE No. 5102, Kevin Turek CCIE No. 7284
Publisher: Cisco Press Pub Date: June 06, 2003
ISBN: 1-58705-120-6 Pages: 432
End-to-end QoS deployment techniques for Cisco Catalyst series switches
Examine various QoS components, including congestion management, congestion
avoidance, shaping, policing/admission control, signaling, link efficiency mechanisms, and classification and marking
Map specified class of service (CoS) values to various queues and maintain CoS values through the use of 802.1q tagging on the Cisco Catalyst 2900XL, 3500XL and Catalyst 4000 and 2948G/2980G CatOS Family of Switches
Learn about classification and rewrite capabilities and queue scheduling on the Cisco Catalyst 5000
Implement ACLs, ACPs, ACEs, and low-latency queuing on the Cisco Catalyst 2950 and 3550 Family of Switches
Understand classification, policying, and scheduling capabilities of the Catalyst 4000 and 4500 IOS Family of Switches
Configure QoS in both Hybrid and Native mode on the Catalyst 6500 Family of Switches Utilize Layer 3 QoS to classify varying levels of service with the Catalyst 6500 MSFC and Flexwan
Understand how to apply QoS in campus network designs by examining end-to-end case studies
Quality of service (QoS) is the set of techniques designed to manage network resources. QoS refers to the capability of a network to provide better service to selected network traffic over various LAN and WAN technologies. The primary goal of QoS is to provide flow priority, including dedicated bandwidth, controlled jitter and latency (required by some interactive and delay-sensitive traffic), and improved loss characteristics.
While QoS has become an essential technology for those organizations rolling out a new