In this post we will look at the basic classification and marking features available in the 3550 and 3560 switches. Basic features include packet marking using port-level settings and port-level policy-maps. Discussing Per-VLAN classification is outside the scope of this document. The Catalyst QoS implementation bases on Differentiated Services model. In a few words, the ideas of this model could be outlined as follows: 1) Edge nodes classify ingress packets based on local policy and QoS label... Read More
In this final part of our blog series on QoS with the PIX/ASA, we examine the remaining two tools that we find on some devices - traffic shaping and traffic policing. Read More
How do you apply most of your QoS mechanisms on a Cisco router? You use the Modular Quality of Service Command Line Interface (MQC). The approach is similar on the PIX/ASA, but the tool does feature some important differences. Also, Cisco has renamed the tool to the Modular Policy Framework. One reason for this is the fact that it is used for more than just QoS. For example, the MPF is also used for application inspection and Intrusion Prevention configurations on the ASA. Read More
Catalyst QoS configuration for IP Telephony endpoints is one of the CCIE Voice labs topics. Many people have issues with that one, because of need to memorize a lot of SRND recommendations to do it right. The good news is that during the lab exam you have full access to the QoS SRND documents and UniverCD content. The bad news is that you won’t probably have enough time to navigate the UniverCD with comfort plus the reference configurations often have a lot of typos and mistakes in them. Read More
QoS features available on Catalyst switch platforms have specific limitations, dictated by the hardware design of modern L3 switches, which is heavily optimized to handle packets at very high rates. Catalyst switch QoS is implemented using TCAM (Ternary Content Addressable Tables) - fast hardware lookup tables - to store all QoS configurations and settings. We start out Catalyst QoS overview with the old, long time available in the CCIE lab, the Catalyst 3550 model. Read More
Inbound 1. QoS Policy Propagation through Border Gateway Protocol (BGP) (QPPB) 2. Input common classification 3. Input ACLs 4. Input marking (class-based marking or Committed Access Rate (CAR)) 5. Input policing (through a class-based policer or CAR) 6. IP Security (IPSec) 7. Cisco Express Forwarding (CEF) or Fast Switching Read More

Subscribe to INE Blog Updates

New Blog Posts!