QoS clarification questions

[mrochac]

good day everyone - i have some confusion in mind in regards to QoS, here is what questioning;

1 ACL base QoS

- if i create a ACL called VOIP (see below); within this ACL i have RTP and Signaling, when i create my class-map to match-all or any how does it work? because when i create my policy-map and say class XXX set dscp EF for voice and one for signally how does it classify according if it all in one ACL? (not sure if this is clear but....)

Extended IP access list Voip-QoS

10 permit udp any any range 16384 32767

11 permit tcp any any eq 5060

12 permit tcp any any range 2000 2002

13 permit tcp any any eq 1720

14 permit tcp any any range 11000 11999

15 permit tcp any any

16 permit ip any any

If i say match-all it will match ALL as per ACL list, if i say match-any will it match according to first come first serv?

Please help.

[Anthony Holloway]

Any VS All is pertaining to your match commands, not how many lines of ACL you have. In your case, by combining RTP and Signaling in the same ACL, it stands to reason that you're classifying and scheduling all of your traffic for phones the same. Did you mean to put it all in one ACL? Can you separate it?

[mrochac]

Thanks for reaching out Anthony - thats a very good point! yes i can separate them but if i can only apply 1 ACL to an interface how will that work? i think i'm not seeing the bigger picture here.

MR

[Anthony Holloway · Accepted solution]

You would never apply this ACLs to the interface. These are non-standard usage of an ACL. They are only used to identify traffic types. You apply the Service Policy to the interface.

[mrochac]

Classification - PUBLIC


That makes sense! Shows you how much I know! So the ACL is used with service-policy when you apply it to an interface correct? That when filtering happens?

MR

[mkazam001 · Accepted solution]

and that what i also said in my earlier post:

you don't apply the acl to the interface - you apply the service-policy, see below example:

interface fa0/0

 service-policy input voip-and_be

regards, mk

[mrochac]

Classification - PUBLIC


Yes now I get, clear! That's what I was so confused about - the ACL is used by the policy-map once you apply it to the interface with service-policy, that's the part I was getting confused with and could grasp around.

Thank you for your help..

[mkazam001]

im in the middle of learning QoS myself - so perhaps the more experienced guys might be able to verify if this is correct:

class-map voip-traffic

 match ip access-group 101

policy-map voip-and-be

 class voip-traffic

  set ip dscp ef

 class class-default

  set ip dscp default

access-list 101 ext permit udp any any range 16384 32767

regards, mk

[mrochac]

Classification - PUBLIC


Hi MK - similar to what I have, actually I'll be using yours!
But, if you have 2 ACL 101 for VOICE and 102 for signaling how do you attached to same interface? That's where I'm confused, I see tones of references to ACL1 and ACL 2 in class-map but how are the ACL being reference if you can only have 1 attached to interface?

MR

[mkazam001]

you'd normally use class-maps to define the different types of traffic - eg. voip media & voip signalling 

i think match ip rtp - will match only the VoIP payload

you don't apply the acl to the interface - you apply the service-policy, see below example:

interface fa0/0

 service-policy input voip-and_be

like i said, im new to this myself, - but you can still rate if helpful/solved :)

regards, mk

[Ashish Patel]

Have you reviewed the QoS Bible https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book/QoSDesign.html#66797 maybe a few years old but still useful to see how to apply QoS. rgs ashish

[mrochac]

Classification - PUBLIC


Hi Ashish - great read and I'm still reading it now, but my question still stands and I see reference to multiple ACL on the link you sent me, but yet, how do you apply 2 ACL to 1 interface? I see multiple ACL, all the config I need is on that link you sent.
If am making reference to an ACL in my class-map, I have to attached that ACL to an interface do I not?

MR