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MariusSunchaserFlag for Romania

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Bandwidth allocation at switch level

Hello experts.

I need a way to manage bandwidth allocation at switch level for a customer. He wants to make sure that some computers in his network have a guaranteed bandwidth, but in the same time they don't exceed that limit.
For instance, he has 10 mbps  from his ISP, and wants to be sure that few computers dedicated to management have 5 mbps guaranteed, but in the same time they don't exceed the 5 mbps limit. So, I thought that the easiest way is to place a switch just before the ISP router and to split the bandwidth at port level, with some ports for management having 5 mbps.

Now, I know that some Cisco Catalyst switches can do that, but I didn't do it until now. Of course Cisco Switches are expensive, so my questions are:
1. Only Cisco Switches do that?
2. If yes, what is the cheapest Cisco Switch that can do that.
3. If not, what other switches can do that?
4. I would like some hints for someone who already did that before, and possibly post some configuration examples.
Avatar of captaink118
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That is not really a good way to do it.
They way it should be done is with QOS.  QOS is configurable on almost all routers.  If you are looking for the cheap route.  Get a Linksys router that supports dd-wrt.  Then you can configure port (thats tcp port) priority.  So for instance you would configure port 21 with a lower priority than lats say port 80.  Due to the large amount of traffic that ftp uses when doing a file transfer.  

I believe dd-wrt does have the capability to specify interface (physical connection) priority but thats not the recommended solution.  
Avatar of MariusSunchaser


captaink118: Thank you for your post.
The ISP manages my client's router. Because of that, I don't want to place another router. There is no need. And again, the client doesn't need protocol based QOS, because it's not a problem of congestion.

As I said, I need port based QOS at switch level. I'll wait for other solutions.
Well you will atleast need a managed switch that can do packet tagging.

Here is where you can look up dd-wrt doing port prioritizing.  
Look at:
Look under the
# 3 Prioritizing by IP Address (Netmask Priority)
# 4 Prioritizing by MAC Address

And here is how you can configure your router to function as a managed switch.
Avatar of SeeMeShakinMyHead

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Awesome, thank you very much for your answer, it's very explicit and detailed.
Now, this limits only outbound traffic, or all traffic?

Do you know what's the cheapest switch that can support this option?
  Using this configuration will it not also limit internal traffic to 5Mb?  That may not be an issue in this case.  But it would be good to know for other possible use cases.
Avatar of SeeMeShakinMyHead

my understanding is only outbound traffic.  You could always test this in a lab environment.
MariusSunchaser if you do go with this solution can you test this case.  I would like to know if it limits traffic internal to that switch also.  This configuration maybe useful in some of my environments if this is the case.
Well guys, thank you for your answers.
It's true that limiting internal traffic too is a thing to consider. I'll present all the options to my client and take a decision.
Because there aren't new answers, i'll close the question and assign points.