Class Map

The Client QoS feature contains Differentiated Services (DiffServ) support that allows traffic to be classified into streams and given a certain QoS treatment in accordance with defined per- hop behaviors.

Standard IP-based networks are designed to provide best-effort data delivery service. Best- effort service implies that the network delivers the data in a timely fashion, although there is no guarantee that it will. During times of congestion, packets may be delayed, sent sporadically, or dropped. For typical Internet applications, such as e-mail and file transfer, a slight degradation in service is acceptable and in many cases unnoticeable. However, on applications with strict timing requirements, such as voice or multimedia, any degradation of service has undesirable effects.

A DiffServ configuration begins with defining class maps, which classify traffic according to their IP protocol and other criteria. Each class map can then be associated with a policy map, which defines how to handle the traffic class. Classes that include time-sensitive traffic can be assigned to policy maps that give precedence over other traffic.

You can use the Class Map page to define classes of traffic. Use the Policy Map page to define policies and associate class maps to them.

Select Client QoS > Class Map in the navigation pane.

Enter a Class Map Name. The name can include from 1 to 31 alphanumeric characters and the following special characters: hyphen, underscore, backslash, and colon. Spaces are not allowed.

Select a value from the Match Layer 3 Protocol list:

IPv4—The class map applies only to IPv4 traffic on the WAP device.

IPv6—The class map applies only to IPv6 traffic on the WAP device.

The Class Map page appears with additional fields, depending on the Layer 3 protocol selected.

Use the fields in the Match Criteria Configuration area to match packets to a class. Select the check box for each field to be used as a criterion for a class and enter data in the related field. You can have multiple match criteria in a class.

The match criteria fields that are available depend on whether the class map is an IPv4 or IPv6 class map.

Select the class map from the Class Map Name list.

Configure the parameters (parameters that appear only for IPv4 or IPv6 class maps are noted):

Match Every Packet—The match condition is true to all the parameters in a Layer 3 packet.

When selected, all Layer 3 packets will match the condition.

Protocol—Use a Layer 3 or Layer 4 protocol match condition based on the value of the IP Protocol field in IPv4 packets or the Next Header field in IPv6 packets.

If you select this field, choose the protocol to match by keyword or enter a protocol ID.

Select From List—Match the selected protocol: IP, ICMP, IPv6, ICMPv6, IGMP, TCP, UDP.

Match to Value—Match a protocol that is not listed by name. Enter the protocol ID. The protocol ID is a standard value assigned by IANA. The range is a number from 0 to 255.

Source IP Address or Source IPv6 Address—Requires a packet's source IP address to match the address listed here. Check the box and enter an IP address.

Source IP Mask (IPv4 only)—The source IP address mask.

The mask for DiffServ is a network-style bit mask in IP dotted decimal format indicating which part(s) of the destination IP address to use for matching against packet content.

A DiffServ mask of 255.255.255.255 indicates that all bits are important, and a mask of 0.0.0.0 indicates that no bits are important. The opposite is true with an ACL wildcard mask. For example, to match the criteria to a single host address, use a mask of 255.255.255.255. To match the criteria to a 24-bit subnet (for example, 192.168.10.0/ 24), use a mask of 255.255.255.0.

Source IPv6 Prefix Length (IPv6 only)—The prefix length of the source IPv6 address.

Destination IP Address or Destination IPv6 Address—Requires a packet's destination IP address to match the address listed here. Enter an IP address in the appropriate field to apply this criteria.

Destination IP Mask (IPv4 only)—The destination IP address mask.

The mask for DiffServ is a network-style bit mask in IP dotted decimal format indicating which part(s) of the destination IP address to use for matching against packet content.

Destination IPv6 Prefix Length (IPv6 only)—The prefix length of the destination IPv6 address.

IPv6 Flow Label (IPv6 only)—A 20-bit number that is unique to an IPv6 packet. It is used by end stations to signify QoS handling in routers (range 0 to 1048575).

IP DSCP—See description under Service Type fields.

Source Port—Includes a source port in the match condition for the rule. The source port is identified in the datagram header.

If you select the field, choose the port name or enter the port number.

Select From List—Matches a keyword associated with the source port: ftp, ftpdata, http, smtp, snmp, telnet, tftp, www.

Each of these keywords translates into its equivalent port number.

Match to Port—Matches the source port number in the datagram header to an IANA port number that you specify. The port range is from 0 to 65535 and includes three different types of ports:

0 to 1023—Well-Known Ports

1024 to 49151—Registered Ports

49152 to 65535—Dynamic and/or Private Ports

Destination Port—Includes a destination port in the match condition for the rule. The destination port is identified in the datagram header.

If you select this field, choose the port name or enter the port number.

Select From List—Matches the destination port in the datagram header with the selected keyword: ftp, ftpdata, http, smtp, snmp, telnet, tftp, www.

Each of these keywords translates into its equivalent port number.

Match to Port—Matches the destination port in the datagram header with an IANA port number that you specify. The port range is from 0 to 65535 and includes three different types of ports:

0 to 1023—Well Known Ports

1024 to 49151—Registered Ports

49152 to 65535—Dynamic and/or Private Ports

EtherType—Compares the match criteria against the value in the header of an Ethernet frame.

Select an EtherType keyword or enter an EtherType value to specify the match criteria.

Select from List—Matches the Ethertype in the datagram header with the selected protocol types: appletalk, arp, ipv4, ipv6, ipx, netbios, pppoe.

Match to Value—Matches the Ethertype in the datagram header with a custom protocol identifier that you specify. The value can be a four-digit hexadecimal number in the range of 0600 to FFFF.

Class of Service—A class of service 802.1p user priority value to be matched for the packets. The valid range is from 0 to 7.

Source MAC Address—A source MAC address to compare against an Ethernet frame.

Source MAC Mask—The source MAC address mask specifying which bits in the source MAC to compare against an Ethernet frame.

For each bit position in the MAC mask, a 1 indicates that the corresponding address bit is significant and a 0 indicates that the address bit is ignored. For example, to check only the first four octets of a MAC address, a MAC mask of ff:ff:ff:ff:00:00 is used. A MAC mask of ff:ff:ff:ff:ff:ff checks all address bits and is used to match a single MAC address.

Destination MAC Address—The destination MAC address to compare against an Ethernet frame.

Destination MAC Mask—The destination MAC address mask specifying which bits in the destination MAC to compare against an Ethernet frame.

VLAN ID—A VLAN ID to be matched for packets. The VLAN ID range is
from 0 to 4095.

The following Service Type fields show for IPv4 only. You can specify one type of service to use in matching packets to class criteria.

IP DSCP—A differentiated services code point (DSCP) value to use as a match criterion:

Select from List—A list of DSCP types.

Match to Value—A DSCP value that you specify, from 0 to 63.

IP Precedence (IPv4 only)—Matches the packet's IP Precedence value to the class criteria IP Precedence value. The IP Precedence range is from 0 to 7.

IP TOS Bits (IPv4 only)—Uses the packet's Type of Service bits in the IP header as match criteria.

The IP TOS bit value ranges between (00 to FF). The high-order three bits represent the IP Precedence value. The high-order six bits represent the IP Differentiated Services Code Point (DSCP) value.

Click Save. The changes are saved to the Startup Configuration.

NOTE To delete a class map, select it in the Class Map Name list and click Delete. The class map cannot be deleted if it is already attached to a policy.