About QoS

QoS implementation in the Cisco MDS 9000 Family follows the differentiated services (DiffServ) model. The DiffServ standard is defined in RFCs 2474 and 2475. The Cisco MDS 9000 Family supports QoS for internally and externally generated control traffic. Within a switch, control traffic is sourced to the supervisor module and is treated as a high priority frame. By default, the QoS feature for certain critical control traffic is enabled. These critical control frames are assigned the highest (absolute) priority. A high priority status provides absolute priority over all other traffic and is assigned in the following cases:

Quality of service (QoS) offers the following advantages:



Copyright © 2002-2007, Cisco Systems, Inc. All rights reserved.