QoS for Cisco Router to Prioritize Voice and Interactive Traffic
- by TJ Huffington
I have a Cisco 891W NATing Voice and Data to the internet over a 10mbit/2mbit connection. Voice traffic gets degraded when I upload large files. Pings time out as well.
I tried to configure a QoS policy but it's basically not doing anything. Voice traffic still degrades when upload bandwidth gets saturated.
Here is my current configruation:
class-map match-any QoS-Transactional
match protocol ssh
match protocol xwindows
class-map match-any QoS-Voice
match protocol rtp audio
class-map match-any QoS-Bulk
match protocol secure-nntp
match protocol smtp
match protocol tftp
match protocol ftp
class-map match-any QoS-Management
match protocol snmp
match protocol dns
match protocol secure-imap
class-map match-any QoS-Inter-Video
match protocol rtp video
class-map match-any QoS-Voice-Control
match access-group name Voice-Control
policy-map QoS-Priority-Output
class QoS-Voice
priority percent 25
set dscp ef
class QoS-Inter-Video
bandwidth remaining percent 10
set dscp af41
class QoS-Transactional
bandwidth remaining percent 25
random-detect dscp-based
set dscp af21
class QoS-Bulk
bandwidth remaining percent 5
random-detect dscp-based
set dscp af11
class QoS-Management
bandwidth remaining percent 1
set dscp cs2
class QoS-Voice-Control
priority percent 5
set dscp ef
class class-default
fair-queue
interface FastEthernet8
bandwidth 1024
bandwidth receive 20480
ip address dhcp
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
auto discovery qos
crypto map mymap
max-reserved-bandwidth 80
service-policy output QoS-Priority-Output
crypto map mymap 10 ipsec-isakmp
set peer 1.2.3.4 default
set transform-set ESP-3DES-SHA
match address 110
qos pre-classify
!
fa8 is my connection to the internet. Voice traffic goes over a VPN ("mymap") to the SIP server. That's why I specified "qos pre-classify" which I believe is the way to classify traffic over the VPN. However even when I ping a public IP while saturating upload bandwidth, the latency is exceptionally high.
Is this configuration correct? Are there any suggestions that might make this work for my setup?
Thanks in advance.
