QOS Videoconferencing HELP! (easy)

[jesusccnp]

 I have cisco router 1900, the router has two operating interfaces g0/0 (connected to wan), g0/1 (connected to lan). We have around 50 mb of bandwidth from our ISP but during peak hours we experience drops outs due to other users and guests network activity and. 

I need some  Video Broadcasts Devices to be prioritized for videoconferencing. Here is the following code i  made for that, i need it to be reviewed please.

enable
copy r s

configure terminal
access-list 1 permit 192.168.0.224 0.0.0.31
class-map video
match access-group 1
exit
policy-map video-police
class video
set dscp af41
bandwidth percent 25
class class-default
fair-queue
exit
int g0/0
service-policy output video-police
do show policy-map

Thanks!

[nixpengu1n · Accepted solution]

Hello,

I would consider this:

1. Classify traffic based on port and protocol rather than on a standard ACL; in your case all the traffic from specific subnet will be prioritized no matter if it is video or not

2. I am not sure what congestion management mechanism you want to use. If video is a business critical and should get through in an event of congestion (and traffic amount is less than 25% of total bandwidth) - use LLQ. If not - consider to use CBWFQ and WRED for other traffic you have to avoid congestion and TCP global synchronization for all traffic

Hope this will help.

[jesusccnp]

Hi, nixpengu1n

Thank you for your reply. 

1. It´s true, i will need to see which ports are using  the videoconferences.

2. You are right, video is a business critical and should get through in an event of congestion.

So should i use the priority command instead of the bandwidth command?

What value do you recommend me for video? here is the new code

enable
copy r s

configure terminal
access-list 1 permit 192.168.0.224 0.0.0.31
class-map video
match access-group 1
exit
policy-map video-police
class video
set dscp af41
priority 50
class class-default
fair-queue
exit
int g0/0
service-policy output video-police
do show policy-map

Thanks.

[nixpengu1n]

Hello,

Based on router architecture and Cisco best practices you should not use more that 25% of your interface bandwidth for LLQ. So based on your requirements I would recommend to calculate what bandwidth you really need for video and then either use LLQ (it is is lower that 25% of your interface bandwidth) or consider CBWFQ with WRED for all traffic (or even shaping or policing if necessary).

But what you can do for now - use 25% for LLQ for your video and see will it suffer or not. If not and everyone is happy - your problem is sorted. If not - investigate further.