[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 617
  • Last Modified:

Cisco Catalyst 3560G-TTS QoS Capabilities


I am wanting to use a Cisco Catalyst 3560G-TTS to shape police bandwidth to our internet (without lowering bandwidth between computers to our internet).  As I understand it, the Cisco Catalyst 3560G-TTS will do that (I'm looking at plugging two WS-C2948G into the 3560G and hooking PCs to the WS-C2948Gs).  

In this configuration, would the Catalyst 3560G limit bandwidth as a whole from the WS-C2948Gs or is it able to see the endpoint connection and limit bandwidth to the individual devices hooked up to the WS-C2948Gs?

0
hayedid
Asked:
hayedid
  • 5
  • 3
1 Solution
 
Jody LemoineNetwork ArchitectCommented:
The QoS control on any switch device is only going to be able to regulate traffic on its own ports, so in the configuration you're proposing, it will regulate traffic from each of the 2948G switches as a whole.  It *can* be specific in terms of addressing specific clients on the 2948G switches, but it will only be able to apply this control on the switch port that the 2948G is connected to.
0
 
Jody LemoineNetwork ArchitectCommented:
That said, the 2948G units are essentially fixed-configuration versions of the Catalyst 4000 family and have QoS support in their CatOS.  If you want to bring QoS as close to the end stations as possible, you may want to look at what you can do on the 2948G units themselves.

http://www.cisco.com/en/US/docs/switches/lan/catalyst4000/7.4/configuration/guide/qos.pdf
0
 
hayedidAuthor Commented:
I was afraid of that.  This being the case, am I better off with some other configuration?  I have 65 PCs sharing a 1.5Mb internet connection.  I was going to but the Catalyst 3560G at the core with the WS-C2948Gs hooked up to it.  Am I better off with a more simple core, and more complex switches plugged into it?  We have two network closets and I was going to put a WS-C2948G in each one.  I read the link you provided, but I think I'm new enough to this that I don't understand the terminology well enough to know whether I'm on the right track.
0
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

 
hayedidAuthor Commented:
I think one of the things I'm not clear on is how these devices can regulate traffic to the internet without slowing internal network traffic.  Is this done by just regulating port 80? or how?

Thanks.
0
 
Jody LemoineNetwork ArchitectCommented:
Are you mostly concerned with prioritizing traffic on your 1.5Mb Internet connection?  If so, then doing it all on the 3560G is reasonable because all Internet traffic will have to go through it anyway.  You only need to go down to the 2948Gs if you're wanting to apply QoS to the LAN traffic.
0
 
Jody LemoineNetwork ArchitectCommented:
QoS can be applied in a number of ways.  In most cases, you're just telling the network device that high-priority traffic gets to jump to the front of the queue when it's being sent to the Internet.  If there *is* no high-priority traffic, then everything functions normally.

Traffic can be assigned a priority by the sending device (in the case of VoIP devices and the like) or it can be applied based on other factors by a switch or router.  If, for example, you want to make sure that web browsing has to take the back seat to everything else, you can tell the switch or router to apply lower than normal priority to anything with a destination port of 80/tcp.  QoS can be manually set based on just about any factor that an extended access list can filter on.
0
 
hayedidAuthor Commented:
My concern is primarily with regulating traffic to the internet.  1.5Mb/s shared by up to 65 people is not working well.  Granted, 65 people are not all using it at the same time.  However, there are some bandwidth hogs somewhere in the network, so I'm wanting some fine grain control.  If I regulate port 80 traffic on the 3560G and someone on one of the 2948Gs is heavily using the internet, then everyone on that 2948G switch would be affected right?  

My other concern is that intranet (not internet) access on port 80 would also be affected... or is there a way to regulate port 80 going outside the network without regulating port 80 inside the network?

Do these questions / concerns make sense?  I can try to re-explain them if I'm not expressing the concerns well enough.
0
 
Jody LemoineNetwork ArchitectCommented:
Yes, they make complete sense.  If you just want to regulate Internet traffic, you can do it by applying QoS only to the Internet-facing VLAN on the 3560G.  That way you can control traffic on the Internet link without slowing anything down on the internal network.  You can still regulate the outbound traffic by source IP if you want to de-prioritize a user on a 2948G.

Given the application you're describing, I'm inclined to think that QoS isn't quite the answer you're looking for.  A caching proxy server like Squid, installed in transparent or WCCP mode, will manage your HTTP access much more effectively and will cache commonly-visited sites so that your Internet connection isn't quite so heavily used.  It will also allow you to pull reports on who the heavy users are so that you can identify them more easily.
0

Featured Post

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

  • 5
  • 3
Tackle projects and never again get stuck behind a technical roadblock.
Join Now