Currently viewing the tag: "qos"

Cisco QoS at-a-glance

By On July 8, 2011 · 1 Comment

Stephan, a  colleague of mine,  found the following documents digging through multiple pages of Cisco.com. The documents present a nice view of different QoS approaches and the most  important information. Somehow like “cheatsheets”. They were helpful to us when need to implement QoS in some parts of the network that we administer. I hope they will help you as well.

Maybe you are wondering why I’m adding them here, since the documents are already somewhere in Cisco.com. As probably you [...]

Continue Reading →

Cisco: Prioritize Voice traffic with LLQ

By On May 19, 2010 · 1 Comment

In one of my previous posts I was explaining how to mark packets closer to network edge. Starting from that point, we are sure the packets are market with the correct value, so on the router device we can directly match those packets and prioritize using Low Latency Queueing.

I believe you already know why queueing is so important for Voice packet especially, but also for all other kind of real time protocol [...]

Continue Reading →

Cisco: Mark voice packets at the network edge

By On May 4, 2010 · 2 Comments

You know how Cisco always advise to mark the packet as close to the your network edge as you can? Even more you can find a lot of example where Cisco show how to trust the packets directly on the access switch, but not all the time you can do this.

First because not everybody has devices that mark correct packets (like Cisco IP Phones) but we still have to [...]

Continue Reading →

Great tool for testing QoS implementation

By On December 16, 2009 · 5 Comments

After my last post, some readers were asking what tool did I used for testing the QoS and how satisfied I’m with it.

The name of the tool is Packgen. According to its developer developers, “Packgen is a simple network packet generator handling diffserv markers, useful for testing network bandwidth and QoS.” It support features like:
– Network packet flows generation with given bandwidth (packets sent at each time interval depending on the bandwidth to produce and the [...]

Continue Reading →

Cisco AutoQoS VoIP

By On November 20, 2009 · Leave a Comment

QoS – one of the most interesting and challenging part of the network engineer’s life. I think I’m not wrong when I’m saying that most engineers that hear the word QoS, react somehow like “ah, that ugly stuff…” I have to be honest and say that QoS is not one of my preferred part, but as a network engineer you have to accomplish all task, not only the one that you like. With QoS you can achieve some great results, and once you have started [...]

Continue Reading →

Routing + QoS + Security all free for you and your small business

By On July 9, 2009 · 2 Comments

OK, you catch me as this is not from Cisco, but is related to networking and security, so I believe it fit in the idea of this blog. What I’m talking about here?! Well, let’s assume that you are the IT guy of one small business or even your home network, and like all of us, you want what’s the best for your network. With today’s key words (even I don’t understand why) like saving, cost reduction, zero budget for new deployments no manager will [...]

Continue Reading →

Cisco: How to selective drop packets without using an access-list

By On March 5, 2009 · 2 Comments

The title actually was a request that I encounter during my CCIE RS preparation. Of course, that in the real world, I would go straight forward and implement an access-list do drop selected packets. But since the lab environment is different for the real one, you might get a task like the above one.

Let’s assume that we have a network topology with a central router (R1) that connects 2 routers (R2 and R3), like in a hub and spoke diagram. Communication between R2 and [...]

Continue Reading →

Cisco: How-to limit HTTP traffic on weekdays during working hours

By On November 19, 2008 · Leave a Comment

Some time ago a person asked me to set the HTTP traffic to 256 kbits during weekdays from 8:00 – 16:00, to limit “the fun” in the office while other are working. In theory I’m against this type of policy, because if you have a team of network engineers and they have to access cisco.com in the same time for information and other stuff like IOS download, then this will take a lot of time. Of course if you see that the productivity is going [...]

Continue Reading →