qos bandwidth per ip address

[harinirina]

Hi,

we'd like to configure qos on our router.

Some ip addresses need more bandwidth when connecting to internet.

The config's as follow

class-map match-any a

match access-group 120

class-map match-any b

match access-group 121

policy-map ilimit

class a

bandwidth percent 40

class b

bandwidth percent 20

interface Ethernet0

description to internet

service-policy output ilimit

access-list 120 permit ip host 192.168.0.2 any

access-list 121 permit ip host 192.168.0.3 any

The output of a "sh policy-map interface e0" shows 0 packet for class-map a and b.

class-default has 18347 packets, 2736652 bytes.

the "show access-list 120 | 121" don't show any matches.

[m-haddad]

Hello,

What type of VoIP are using. This is because VoIP protocols differ from one application and vendor to the other. I have done the below bandwidth division while using LLQ for RTP traffic.

ip cef

class-map match-all VoIP

math protocol RTP

class-map Match-all Manager

match access-group 120

policy-map QoS

class voip

priority percent 30

class Manager

bandwidth percent 40

class class-default

bandwidth percent 30

interface Ethernet0

bandwidth 500

max reserved-bandwidth 100

service-policy output QoS

access-list 120 permit ip host 192.168.0.2 any

The above will guarantee

30 for VoIP RTP traffic

40 for your Manager

30 for all other user's internet traffic

The above policy would only start or take effect when the 500Kbps gets congested.

Please let me know if this solves your scenario,

Appreciate your rating,

Regards,

[harinirina]

Hi,

Thanks for the config, do we need to specify bandwidth for http for only few users or is it unecessary ?

we'll try it and i'll let you know.

what do you use to monitor qos?

[m-haddad]

Hello,

Hope this configuration works as per your requirements. To monitor the effieciency of the policy, try to get the link congested and issue the command "show ip policy interface e0/0" then check the counters and matches.

Remark: e0/0 is the interface where you applied the policy.

Let me know how it goes,

Regards,

[harinirina]

Hi,

We used 2 classes for test.

We've tested qos by launching many download in 2 pcs of different class.

here's the output of show policy-map e0

Class-map: a (match-any)

52886 packets, 3437122 bytes

5 minute offered rate 7000 bps, drop rate 0 bps

Match: ip dscp ef (46)

52886 packets, 3437122 bytes

5 minute rate 7000 bps

Queueing

Output Queue: Conversation 265

Bandwidth 40 (%)

Bandwidth 1 (kbps)Max Threshold 64 (packets)

(pkts matched/bytes matched) 271/20948

(depth/total drops/no-buffer drops) 0/0/0

Class-map: b (match-any)

0 packets, 0 bytes

5 minute offered rate 0 bps, drop rate 0 bps

Match: ip dscp af41 (34)

0 packets, 0 bytes

5 minute rate 0 bps

Queueing

We've tested different values for bandwidth just for test.

There's no packet drop, no queue depth.

What's the interpretation of the result, how to know if the appropriate bandwidth was affected per class ?

[m-haddad]

Hello,

Can you please the latest Config?

Thanks,

[harinirina]

Hi,

Like your config but we don't have put yet the class voip,we've put another class with acl

class-map match-any a

match access-group 120

class-map match-any b

match access-group 121

policy-map p_in

class a

set ip dscp ef

class b

set ip dscp af41

int f0

to LAN

service-policy input p_in

class-map match-any c

match ip dscp ef

class-map match-any d

match ip dscp af41

policy-map p_out

class c

bandwidth percent 40

class d

bandwidth percent 20

int e0

to the internet

bandwidth 500

service-policy input p_out

Regards

[m-haddad]

Sorry for not getting back to you earlier. In the above configuration you are just guarnteeing bandwidth for the classes. However, for VoIP it is better to use priority because they require to exit the queue before any other traffic.

As for the show output your policy is taking effect but it didn't reach the stage where it starts dropping packets. Therefore, things looks from the perspective of the show output.

Appreciate your rating and let me know if you need anything else,

Regards,

[harinirina]

Hi Haddad,

We will use the protocol RTP for voip.

It's not yet in use.

What can you say about the output above?

Is there any more information you need?

[m-haddad]

If you are going to use RTP then it is better to use the below class.

class VoIP_RTP

match protocol RTP

PLease let me know if you need anything further,

Regards,

[harinirina]

Hi Haddad,

Our problem is that the connection seems so slow for all classes,when we look at the post-policy and pre-policy bit rate, we've got the same graph.it seems as that's there's no congestion.

Is it normal?

[m-haddad]

Hello,

How much is your exact internet pipe?

Let me know,

Regards,

[harinirina]

Hi,

it's 512Kb, shared, it's not a guarented bandwidth.

While doing the test, we've used many different values for bandwidth.

[m-haddad]

Hello,

It is very tough to do QoS on a shared pipe. This is because you are never guaranteed the bandwidth you've got on the interface. THerefore, the QoS should be based on your guaranteed bandwidth.

That is if your guaranteed bandwidth is 256Kbps you have to base your QoS on this band and not on the 512 because sometimes the ISP would be giving you 256Kbps for example and your router won't know that it has to activate the QoS until it reaches the 512Kbps congestion state. Therefore, your QoS would never queue and drop traffic according to matches.

Hope this helps,

Appreciate your rating,

Regards,

[harinirina]

Hi,

We've also tested qos by using "bandwidth 3" for eth0, we didn't see queued / dropped packet.

How to see if it reaches 3Kbps ?

[ilya.varlashkin]

The thing is congestion first occurs not on your 10Mbps interface, but whatever is the next device (a DSL modem/provider managed CPE?). That's why you don't see queued/dropped packets - they're not dropped by your router, but by next device.

Configuring bandwidth on the interface does nothing to restrict speed of the interface, it's only informational parameter which is used to calculate many operational parameters but it doesn't police traffic. In such situation you need to configure two-level hierarchical QoS - in the parent policy you define traffic shaping to whatever actual access link speed is, then you specify child policy to do CBWFQ. For example:

policy-map MyQoS

class A

band perc 40

class B

band perc 20

policy-map QoS-512

class class-default

shape ave 512

servcie-policy MyQoS

!

interface Eth0

service-policy QoS-512

Then you'll see queued/dropped packets.

Hope it helps.