qos - is there an easy way to categorise an application

Unanswered Question

Hi all,

My question relates to QoS.

We do not use Voice or Video on the data network, however, I would like to classify our many existing data applications (around 500) into 4 QoS classes, these being Interactive and Transactional (http, telnet etc), Bulk (ie ftp, Exchange etc), Best Effort and Scavenger class.

The question is, is there an easy way to establish what type of category a specific application should be classified under (eg. transactional, bulk, Scavenger etc).

Obviously some are easily identified but many others are not?

Is there a web site for example, I can input a common application name and/or port number and it recommends this should go under a specific class.

Hope you can help.

Kind regards


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Overall Rating: 2.5 (2 ratings)
Manoj Wadhwa Tue, 07/03/2007 - 10:29
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NBAR seems to be the easiest way to categorize an application. But you will have to check out if your application is being supported by NBAR. If not, you will have to rely on traditional ACL statements.

- Manoj


Thanks for responding.

Nbar produces a long list of applications/protocols but this does not specify which is transactional, bulk etc. As I mentioned some highlighted by Nbar are obvious (eg http, ftp etc) but many listed I am not able to determine what category these should fit under.

Do you know how I can determine this information?



Manoj Wadhwa Tue, 07/03/2007 - 14:35
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I guess i got what you are looking for. You would like to know what category should you fit each application into, right? Well, i dont think there would be any website that would mention this, reason is because this purely depend upon the needs of the organization. For eg. for a banking organization, http traffic might be a high priority whereas for another organization, it might be of lowest priority. Hence there is no standard of what application should fit in what class. This is where the flexibility of class-maps comes into picture. You should actually look into the requirements of your organization and accordingly assign them to their specific class.

- Manoj

Hi Manoj,

No, you have not understood what I am looking for.

Let me try and explain it another way. If I have a long list of applications that are running on the network, and lets pick one called application X. The problem is I have no knowledge of what application X does and therefore I cannot place this application in either the transactional, bulk or best effort class without further information.

So I was asking is there a web site for example, that I could input as many details as I have about this application (eg port number) and the response would be something like 'this is normally associated with file transfers etc etc.... I would then be able to place this specific application (application X) under the bulk class (as apposed to any other class).

Hope you understand what I am trying to achieve now.

Thanks for your time on this.



mheusing Wed, 07/04/2007 - 08:04
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  • Cisco Employee,


The tricky thing is that there are applications configured to not use the standard port numbers (like web servers on port 8080 and the like) and also applications, which are not using assigned numbers at all. Also be aware of programs allowing to configure port numbers - you can setup emule clients to use TCP port 80 for file sharing, but I doubt that you want to prioritize this in a production environment.

As already pointed out in a previous posting, the underlying fundamental problem with DiffServ is: YOU need to decide, what is important and what not in a first step. The second step is to identify those applications to your network equipment (class-maps) and to implement a policy reflecting its importance.

Unfortunately there is no "one fits all" approach possible.

This task is not an easy one, but for a start have a look at:


This lists assigned TCP/UDP port numbers. Not exactly what you want, but a starting point.

One other approach would be to use Auto-QoS for the enterprise, where Cisco tried to do this for a limited number of applications within IOS. For further details have a look at "AutoQoS for the Enterprise"


Hope this helps!

Regards, Martin


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