3com WX4400 3CRWX440095A Manuel D’Utilisation
Enabling Prioritization for Legacy Voice over IP
401
The following commands perform the same CoS reassignment as the
commands in “Using the dscp Option” on page 400. They remap IP
packets from IP address 10.10.50.2 that have DSCP value 46 (equivalent
to precedence value 5 and ToS value 12), to have CoS value 7 when they
are forwarded to any 10.10.90.x address on Distributed MAP 4:
commands in “Using the dscp Option” on page 400. They remap IP
packets from IP address 10.10.50.2 that have DSCP value 46 (equivalent
to precedence value 5 and ToS value 12), to have CoS value 7 when they
are forwarded to any 10.10.90.x address on Distributed MAP 4:
WX1200# set security acl ip acl2 permit cos 7 ip 10.10.50.2
0.0.0.0 10.10.90.0 0.0.0.255 precedence 5 tos 12
success: change accepted.
WX1200# set security acl ip acl2 permit cos 7 ip 10.10.50.2
0.0.0.0 10.10.90.0 0.0.0.255 precedence 5 tos 13
success: change accepted.
WX1200# set security acl ip acl2 permit any
success: change accepted.
WX1200# commit security acl acl2
success: change accepted.
WX1200# set security acl map acl2 ap 4 out
success: change accepted.
0.0.0.0 10.10.90.0 0.0.0.255 precedence 5 tos 12
success: change accepted.
WX1200# set security acl ip acl2 permit cos 7 ip 10.10.50.2
0.0.0.0 10.10.90.0 0.0.0.255 precedence 5 tos 13
success: change accepted.
WX1200# set security acl ip acl2 permit any
success: change accepted.
WX1200# commit security acl acl2
success: change accepted.
WX1200# set security acl map acl2 ap 4 out
success: change accepted.
The ACL contains two ACEs. The first ACE matches on precedence 5 and
ToS 12. The second ACE matches on precedence 5 and ToS 13. The IP
precedence and ToS fields use 7 bits, while the DSCP field uses only 6
bits. Following the DSCP field is a 2-bit ECN field that can be set by other
devices based on network congestion. The second ACE is required to
ensure that the ACL matches regardless of the value of the seventh bit.
ToS 12. The second ACE matches on precedence 5 and ToS 13. The IP
precedence and ToS fields use 7 bits, while the DSCP field uses only 6
bits. Following the DSCP field is a 2-bit ECN field that can be set by other
devices based on network congestion. The second ACE is required to
ensure that the ACL matches regardless of the value of the seventh bit.
You cannot use the dscp option along with the precedence and tos
options in the same ACE. The CLI rejects an ACE that has this
combination of options.
options in the same ACE. The CLI rejects an ACE that has this
combination of options.
Enabling
Prioritization for
Legacy Voice over
IP
Prioritization for
Legacy Voice over
IP
MSS supports Wi-Fi Multimedia (WMM). WMM support is enabled by
default and is automatically used for priority traffic between
WMM-capable devices.
default and is automatically used for priority traffic between
WMM-capable devices.
MSS also can provide prioritization for non-WMM VoIP devices. However,
to provide priority service to non-WMM VoIP traffic, you must configure
static CoS or configure an ACL to set the CoS for the traffic. The MAP
maps the CoS value assigned by static CoS or the ACL to a forwarding
queue. The examples in this section show how to configure CoS using
ACLs. To use static CoS instead, see “Configuring Static CoS” on
page 343.
to provide priority service to non-WMM VoIP traffic, you must configure
static CoS or configure an ACL to set the CoS for the traffic. The MAP
maps the CoS value assigned by static CoS or the ACL to a forwarding
queue. The examples in this section show how to configure CoS using
ACLs. To use static CoS instead, see “Configuring Static CoS” on
page 343.