The battle for bandwidth.

So I saw a post over at Ioshints about bandwidth, how we, as consumers come to expect a certain bandwidth, and how ISP’s are dealing with these issues. It is a fact that ISP’s greatly oversubscribe their networks, and keep selling more access-lines with an even greater bandwidth cap than ever before.
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OSPF and some interesting facts.

Even though my next post was going to be about some enhancements to STP, I found this little nugget about OSPF behavior, that I thought I would share with everyone. As we know OSPF, when crossing an area boundary, the ABR (Area Border Router), will gather type 1 (router and its links) and type 2 (network information provided by the DR on a transit network) and form a type 3 LSA, which is basically a boiled down version of the two other types of LSA’s.
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Back on the horse…

I failed my first attempt at the CCIE written exam this thursday… It really sucks. I was very close to passing it, but unfortunally it didnt happen. I need alot more practice questions to get a “feel” of whats being asked.
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Google Wave

I am just watching the video of the google wave application. It is really impressive what you can do with the modern web technologies. One thing that really shines through is the real-time updating. This is a really cool technology that I can envision a bright future.
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ACL and Wildcard masks

Been spending the last few days doing some leg-work on understanding different ACL’s to match different networks most effeciently. Alot of posting on Online-Study List on how to do this, all very valuable. Tyson Scott from IPexpert created a PDF file that was posted, and will also be made available from IPexpert.
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PIM-SM, part 2

So this is the 2nd part on how PIM-SM operates. Last time I showed how the initial RPT (shared tree) was constructed, and how data would flow from the source to the receiver. This time, I want to show you how the optimization technique in SM actually works.
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What is it with google?

I am really wondering whats up with google’s services lately. I have been having huge issues getting my mail. It times out several times, and then all of a sudden it appears, and other times it logs me out. Sometimes I have to periodically refresh.
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Tackling the multicast beast.

Ive started on the Developing IP Multicast Networks book from Beau Williamson. This book is apparently “the” book on multicasting, so I hope it will help me out with this weak area of mine. So far ive read about DVMRP which is not on the blueprint, but it sounded like it would be a good help to understanding PIM modes, which are on the blueprint, so I decided to go through it anyways.
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BGP in all its glory.

I am almost done with the Internet Routing Architectures book, and its a great book!! You really get to understand why BGP is the way it is. Where IGP’s as we know them concentrate on fast convergence, BGP is all about 2 things: stability and policies.
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Discipline needed.

So even though im looking over my journal, and i am doing about 1,5 – 2 hours studying each day, I feel like im lacking the discipline to really make a dent in the thing called CCIE Written. I have not been using google calendar like i should, and it is really bumming me out.
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New blueprint.

The new blueprint is out for all to see. Its version 4, and includes some interesting things. Alot of people have already analysed it in quite some detail. The two things thats most obvious to me, is the emphasis on MPLS as more and more dominant technology.
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Shaping and policing

As the topic implies, I will be writing about a few things regarding shaping and policing. Now these are two really hard-to-understand topics for me, but they are also very usefull. To understand what they do, and the difference between them, lets define them as such:
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Incomming material and more reading.

Im at the policing and shaping section of the exam certification guide, and its very hardcore stuff in my opinion. Just finished the section on 3550 and 3560 ingress/egress queuing and scheduling methods. Wow, thats really something i gotta get my head around.
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Framework and labs.

Im somewhat in the middle of the CCIE exam certification guide, and still learning alot. I am putting down the framework for more detailed examination of technologies. I have a couple of books on my reading list after this to solidify the knowledge with more in-depth details.
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Labs, labs, labs.

I am doing alot of technology focused labs, and I always learn something new, which is really good. For example, I was studying the effects of autosummarization with RIP and EIGRP. A few things cropped up. RIP will autosummarize routes it receives from other neighbors, where as EIGRP will only summarize those, if it has a locally connected network of the same major net, and it is included in a network statement.
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Update.

Im done with my first reading of Routing TCP/IP volume 1. All in all a great book, with lots of information about the various IGP’s. I skipped the IS-IS part simply because its not part of the R&S written blueprint. I made quite a few notes about each chapter along the way, which I am sure will come in handy when reviewing/troubleshooting material.
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IPexpert BLS purchased

So I broke down and bought the IPexpert Blended Learning Solution the day before yesterday. I got great advice very fast from the people there, and they were very nice. Been looking over the workbooks, they seem really good and challenging πŸ™‚ As I have written before, I will take my time and learn as much as I possibly can, so I wont even start those labs until I have a better understanding of the entire scope of this whole CCIE buisness, which in other words means alot more reading and understanding of things and passing the written exam.
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IPexpert vLectures

Im watching some free vLectures from IPexpert here, the one im watching is the one about Spanning-Tree. Its pretty good so far. I do hope however, that their video-on-demand products are alot better quality. Im still waiting to take the plunge and buy their BLS (Blended Learning Solution) until I know where I stand both financially and knowledge wise (written).
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EIGRP metrics and best path calculation.

So im finishing up some troubleshooting exercises in Routing TCP/IP. They are mainly about the metrics used by EIGPR. Here’s a review of the functionality of EIGRP and how it chooses the best path to a destination. First of, EIGRP is an Enhancement of the proprietary IGRP protocol, which is almost but phased out by now.
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EIGRP and DUAL

So im reading about EIGRP’s DUAL algorithm, and how it works, and MAN, its confusing. After the example in Routing TCP/IP, even they mention it might require several readings. Basically it boils down to the fact if a router being notified of a bad link has a feasible successor or not.
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Using flash cards.

I wanted to post a link to a great site which I have started using called flashcarddb.com, what it does is pretty simple, but it does its job in a slick fashion. There is a system called the leitner system, which in all its simplicity is making you remember things by repeating them in periods with different intervals.
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Fun with static routes.

Im having some “fun” with static routes. Its an okay topology, 4 routers connected. The task asked for having some floating static routes, along with some load-balancing routes. Since they are CEF based, it will be load-shared by default to destination load sharing.
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ONT done.

I am finally done. ONT was passed today, and with a pretty good score as well. I am very happy. Now it is time for some relaxing, and get on with my training schedule. I really wish we had a testing center somewhere closer that was actually worth going to.
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Labs and review.

I am in the process of reviewing and labbing from the lab portfolio. I need to have the verification commands down, so I can troubleshoot different QoS scenarios. I find it very hard to do much configuration though. Also, the wireless section is kind of hard to get good hands-on experience with since I dont have access to any WCS (Wireless Control System).
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Wireless and onto labs.

So I am almost done with the wireless section, but alot of things still needs to click in, especially regarding the security aspect of it all. Some more reading on that is needed next. QoS in wireless is done by basically lowering the back-off time in CSMA/CA for higher priority traffic.
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Wred, compression and LFI

I am finishing up on chapters regarding WRED and LFI. WRED is a congestion avoidance mechanism. What that means, is that when congestion occurs, you try and avoid filling up the buffers completely by dropping some packets. Normally the standard queueing for fast interfaces (>E1) is FIFO, with the congestion avoidance of tail dropping.
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Congestion management and queues.

So im studying about congestion management, namely the use of queuing and the different discplines of queuing. FIFO = First In First Out. This is a straight forward queue which doesnt take any priority, delay or bandwidth into account. This is the default on Cisco equipment for interfaces > 2.
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