[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now

x
?
Solved

QOS for switch and router

Posted on 2008-11-11
5
Medium Priority
?
1,002 Views
Last Modified: 2012-05-05
Say i have a voip phone connected to a swich and i use auto qos on the switch for all teh FA and trunk port to the router.  On the router do i need auto qos trust on both the ehternet connection to the switch and the serial interface outbound or just the serial interface ourtbound?

0
Comment
Question by:maxis2cute
  • 3
  • 2
5 Comments
 
LVL 10

Expert Comment

by:kyleb84
ID: 22936117
Both, because there are always 2 streams when using VoIP, one stream to the VoIP device, and a stream to the destination. Therefore you want the router to obey QoS values at each side of the router (Fa + Ser)
0
 
LVL 6

Author Comment

by:maxis2cute
ID: 22936133
i dont disagree, i just want to be 100 percent.  If i have auto qos trunst on the switchport trunk interface, does that not trust the markings from the router?  and if i dont have trust on the ethernet connection to the router will it drop the markings or will it reclassify?

0
 
LVL 10

Expert Comment

by:kyleb84
ID: 22936150
trust qos will only trust ingress (from device, into a port) traffic, outgoing traffic (from the router, to a device) is automatically trusted.

If you have no "trust qos" on your switchport interface all outgoing traffic is trusted, incoming is reclassified.

0
 
LVL 6

Author Comment

by:maxis2cute
ID: 22936284
so one more time and then i will accept your answer.  

switch QOS trust on a voice port--trust the cos from phone
switch QOS trust on trunk port-trust ip prec from router
qos trust on ethernet--trust markings from switch w/o reclassifying, if no trust will it reclasify or drop marking?

qos serial service policy output will send to next router.

0
 
LVL 10

Accepted Solution

by:
kyleb84 earned 2000 total points
ID: 22936357
"switch QOS trust on a voice port--trust the cos from phone"
- Bingo

switch QOS trust on trunk port-trust ip prec from router
- (Yes) by default, that command will trust DSCP from the router.

qos trust on ethernet--trust markings from switch w/o reclassifying, if no trust will it reclasify or drop marking?
- Yes, and...
- (no trust) Reclassify if QoS policy is applied to router/switch, remove QoS if no policy.

qos serial service policy output will send to next router.
- The next router won't receive service-policy details of the previous, only COS/DSCP values.
- You must explicitly set the ip prec in a global policy applied to that interface.
See attached code.

!
! 'match' can be anything that will catch your VoIP traffic.
!
class-map voicetraffic
 match protocol rtp audio
!
policy-map defaultqos
 class voicetraffic
  set ip precedence 4
!
interface Serial 0/0/0
 service-policy output defaultqos
!

Open in new window

0

Featured Post

New feature and membership benefit!

New feature! Upgrade and increase expert visibility of your issues with Priority Questions.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Shadow IT is coming out of the shadows as more businesses are choosing cloud-based applications. It is now a multi-cloud world for most organizations. Simultaneously, most businesses have yet to consolidate with one cloud provider or define an offic…
This article will show how Aten was able to supply easy management and control for Artear's video walls and wide range display configurations of their newsroom.
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

872 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question