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	<title>Cisco Certified Hell &#187; Exams</title>
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		<title>Cisco Certified Hell &#187; Exams</title>
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		<item>
		<title>Beta Results Came Back (Finally)</title>
		<link>http://ciscocertifiedhell.com/2009/11/13/beta-results-came-back-finally/</link>
		<comments>http://ciscocertifiedhell.com/2009/11/13/beta-results-came-back-finally/#comments</comments>
		<pubDate>Fri, 13 Nov 2009 11:29:55 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[CCIE Written]]></category>
		<category><![CDATA[Exams]]></category>

		<guid isPermaLink="false">http://ciscocertifiedhell.com/2009/11/13/beta-results-came-back-finally/</guid>
		<description><![CDATA[After almost exactly 8 weeks since I took the 350-001 beta, I got my results back. (See my previous post for the background on this) I ended up with a 623, which given the little studying I did, makes me feel pretty good. Let&#8217;s just say that I really need to hit multicast pretty hard. [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=216&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>After almost exactly 8 weeks since I took the 350-001 beta, I got my results back. (See my previous post for the background on this)</p>
<p>I ended up with a 623, which given the little studying I did, makes me feel pretty good. Let&#8217;s just say that I really need to hit multicast pretty hard. So with the right amount of preparation, the written should be relatively simple..I hope.</p>
<p>I need to get back into the game here soon. The little one has somewhat of sleep schedule now, but it just doesn&#8217;t necessarily agree with my peak study times! (ie she&#8217;s awake around 4am &#8212; I&#8217;m still operating in zombie mode)</p>
<p>Reading through the success stories on ieoc.com has helped get my motivation going, now it&#8217;s just time to do something about it.</p>
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			<media:title type="html">Gerren</media:title>
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		<title>CCIE Written v4.0 Tomorrow!</title>
		<link>http://ciscocertifiedhell.com/2009/09/08/ccie-written-v4-0-tomorrow/</link>
		<comments>http://ciscocertifiedhell.com/2009/09/08/ccie-written-v4-0-tomorrow/#comments</comments>
		<pubDate>Wed, 09 Sep 2009 01:32:54 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Exams]]></category>
		<category><![CDATA[General Announcements]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=212</guid>
		<description><![CDATA[Tomorrow, I get to look forward to finding out how poorly I did in 6-8 weeks. My main focus tomorrow will be on how the written exam is &#8220;written.&#8221; Basically, is it similar to the the CCNP exams, or is it something completely different. I suppose it&#8217;s not a great way to go about it, [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=212&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>Tomorrow, I get to look forward to finding out how poorly I did in 6-8 weeks. My main focus tomorrow will be on how the written exam is &#8220;written.&#8221; Basically, is it similar to the the CCNP exams, or is it something completely different. I suppose it&#8217;s not a great way to go about it, but I basically want to find out what&#8217;s on the test. I know that each version of the written will vary of course, but I guess the best way to phrase it is &#8220;How do they cram about 90 individual topics (on the blueprint) into 100 questions?&#8221;</p>
<p>Let&#8217;s see what happens! I am looking forward to a fresh start again though in a few months. Mad props to all of you who manage to pull off the CCIE while working and having a family! Once we find out what life with a newborn is like, I will be able to get a better idea of the (realistic) amount of time I can devote per day to studying and go from there.</p>
<p>I&#8217;ve learned that from the few short weeks I&#8217;ve been studying, I need to devote more time to each topic to completely understand it and master it. I started off by creating a pretty rigorous study schedule and found that as time went by, I would rush to finish reading the material just in order to keep up with &#8220;my schedule.&#8221; I know that I need to have some sort of time line to actually pull this off, but it needs to be realistic and allow me to grasp the material and not just &#8220;read it&#8221; for the sake of reading it.</p>
<p>I also think that I&#8217;ll revert back to my original strategy of studying for the lab, and taking the written sometime during that time. I&#8217;ve found that the layer 2 material I studied using a combination lab/reading approach has stuck with me much more than the material that I&#8217;ve simply just read through, and not really labbed out.</p>
<p>So, with all of that said&#8230;I&#8217;m checking out for now. I&#8217;ll post my thoughts on the beta written sometime later this week, but aside from that, I&#8217;m out until further notice and in final countdown for arrival of Baby Smurf.</p>
<p>Good luck to everyone in their studies!</p>
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		<slash:comments>1</slash:comments>
	
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			<media:title type="html">Gerren</media:title>
		</media:content>
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		<item>
		<title>Staying Motivated During CCIE Prep</title>
		<link>http://ciscocertifiedhell.com/2009/08/08/staying-motivated-during-ccie-prep/</link>
		<comments>http://ciscocertifiedhell.com/2009/08/08/staying-motivated-during-ccie-prep/#comments</comments>
		<pubDate>Sat, 08 Aug 2009 14:22:57 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Exams]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=208</guid>
		<description><![CDATA[I&#8217;ve only been at this 3 weeks, and am finding it hard to stay motivated. I’ll have a really good week of studying/videos/labbing, etc. but then the weekend rolls around (today for example), and I have little desire to sit here and read about HDLC, PPP, and everything that goes along with it. I think [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=208&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>I&#8217;ve only been at this 3 weeks, and am finding it hard to stay motivated. I’ll have a really good week of studying/videos/labbing, etc. but then the weekend rolls around (today for example), and I have little desire to sit here and read about HDLC, PPP, and everything that goes along with it.</p>
<p>I think it&#8217;s more of the overwhelming amount of information one tries to absorb during this time, versus not enjoying the material. Sure, some of it’s pretty dry, but all in all, I still find most of it enjoyable. It just feels that even thought I’m making good progress (I think…), there’s so much more to absorb, remember, regurgitate, repeat, etc. This material has to become part of who you are, not just a collection of memorized facts stored away for future use.</p>
<p>I think that’s the part I have a hard time with…trying to determine which specific facts about the technology/protocol are important to remember permanently, versus which facts are needed, but easy to correlate with the task/question at hand during the written and lab exams. I know that I understand the concept and how a protocol works, but I worry about not remembering that one random fact.</p>
<p>The more I read about some of the OEQ horror stories, the more I become concerned. I can’t imagine putting in all this time, just to be shot down for 4 lousy questions. Sure, the concept of the OEQ is well-intentioned, but the results seem to be discouraging. I know there are people that still pass, but as time goes on, the OEQ’s weigh heavily on my mind.</p>
<p>I think part of the other issue is that the network I manage on a day to day basis is very small, and most of the CCIE topics are generally not something I can use/implement daily. I’m sure there are many out there in a similar situation, so how do you stay motivated? What gives you that extra kick to keep going? Coffee is having limited success for me at the moment….*sigh*</p>
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			<media:title type="html">Gerren</media:title>
		</media:content>
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		<item>
		<title>Week 1 Down&#8230;??? to Go</title>
		<link>http://ciscocertifiedhell.com/2009/07/26/ccie-written-prepweek-1/</link>
		<comments>http://ciscocertifiedhell.com/2009/07/26/ccie-written-prepweek-1/#comments</comments>
		<pubDate>Mon, 27 Jul 2009 02:11:39 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[CCIE Written]]></category>
		<category><![CDATA[studying]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=190</guid>
		<description><![CDATA[For various reason, which for now will remain a mystery, a I lost a lot of motivation this week, but still managed to get in a decent chunk of studying. Instead of updating several sources, I&#8217;ve made my time tracking sheet available as a Google doc. This link will take you to the public spreadsheet [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=190&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>For various reason, which for now will remain a mystery, a I lost a lot of motivation this week, but still managed to get in a decent chunk of studying. Instead of updating several sources, I&#8217;ve made my time tracking sheet available as a Google doc.<a title="CCIE Writte Study Tracker" href="http://spreadsheets.google.com/pub?key=t2e6nlT2gzj8XHb6tzQ6XKQ&amp;output=html" target="_blank"> This link</a> will take you to the public spreadsheet I am using to keep track of my hours.</p>
<p>Friday and Saturday were my weak days, which both tie in to the lack of motivation. I managed to get back into the game on Sunday with a solid 4+ hours, but I would&#8217;ve liked to do more.  The past week has been dedicated to spanning tree, and all of its various incarnations. I forgot how much I liked studying spanning tree&#8230;or maybe I should say that I&#8217;ve come to like spanning tree more as time goes on. This coming week will be focused on VLANs and VTP, along with Etherchannel.</p>
<p>I&#8217;m going to try this week to see if I can get my company to cover the cost of ordering the INE CCIE 2.0 study package. The only thing I need to figure out is if they are going to have a CCIE R&amp;S v4 package out soon. I want to dive in and get started, but don&#8217;t want to buy the v3 package if its going to be updated soon.</p>
<p>Anyhow, hopefully this week I can stay focused a bit more.  I think I&#8217;ve managed to get myself out of the funk that I was in, but we&#8217;ll see how the week plays out.</p>
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			<media:title type="html">Gerren</media:title>
		</media:content>
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		<title>CCIE R&amp;S Written Exam Prep</title>
		<link>http://ciscocertifiedhell.com/2009/07/19/ccie-rs-written-exam-prep/</link>
		<comments>http://ciscocertifiedhell.com/2009/07/19/ccie-rs-written-exam-prep/#comments</comments>
		<pubDate>Sun, 19 Jul 2009 15:16:25 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[CCIE Written]]></category>
		<category><![CDATA[Preparation]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=174</guid>
		<description><![CDATA[I&#8217;ve begun the task of preparing for the written exam, and I have to say that the concept of actually passing this thing is a bit overwhelming. I&#8217;m sure that most people feel that way at first, but holy hell! there&#8217;s so much damn information to keep track of. I&#8217;ve started using Google tasks to [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=174&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>I&#8217;ve begun the task of preparing for the written exam, and I have to say that the concept of actually passing this thing is a bit overwhelming. I&#8217;m sure that most people feel that way at first, but holy hell! there&#8217;s so much damn information to keep track of.</p>
<p>I&#8217;ve started using Google tasks to try and keep me on track. So far, I&#8217;ve broken down section 1.10 of the<a title="CCIE R&amp;S v4.0 Written Exam Blueprint" href="https://cisco.hosted.jivesoftware.com/docs/DOC-4374" target="_blank"> R&amp;S v4.0 Written Exam Blueprint</a> and I&#8217;ve got a full week scheduled (damn you spanning tree and all of your diabolical offspring). It&#8217;s painful to think that there&#8217;s 11 main topics to cover!</p>
<p>For those of you that are interested, I&#8217;ve started bookmarking sites that I will be using/reading in accordance with the lab topics and have tried to categorize them using the exam topic number (for example &#8211; 1.10 is spanning tree). You can view my list here: <a title="Linkage. Pure and simple." href="http://delicious.com/gerren.murphy" target="_blank">http://delicious.com/gerren.murphy</a></p>
<p>Does anyone have any good tips on keeping things straight during their exam prep?</p>
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			<media:title type="html">Gerren</media:title>
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		<title>ONT &#8211; IP Quality of Service</title>
		<link>http://ciscocertifiedhell.com/2009/07/02/ont-ip-quality-of-service/</link>
		<comments>http://ciscocertifiedhell.com/2009/07/02/ont-ip-quality-of-service/#comments</comments>
		<pubDate>Thu, 02 Jul 2009 11:10:39 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Exams]]></category>
		<category><![CDATA[ONT]]></category>
		<category><![CDATA[QoS]]></category>

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		<description><![CDATA[Also available as a PDF here Introduction to QoS Converged Network Issues Related to QoS Acceptable end-to-end delay for VoIP packets ~ 150 to 200 ms 4 major challenges/concerns with converged networks Available bandwidth End-to-end delay Delay variation (jitter) – difference in amount of delay Packet loss – usually caused by sudden burst or failures [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=128&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>Also available as a PDF <a title="642-845 Chapter 2 Notes" href="http://www.ciscocertifiedhell.com/wp-content/uploads/2009/07/ont-ip-quality-of-service.pdf" target="_blank">here</a></p>
<h3>Introduction to QoS</h3>
<h4>Converged Network Issues Related to QoS</h4>
<ul>
<li>Acceptable      end-to-end delay for VoIP packets ~ 150 to 200 ms</li>
<li>4      major challenges/concerns with converged networks
<ul>
<li>Available       bandwidth</li>
<li>End-to-end       delay</li>
<li>Delay       variation (jitter) – difference in amount of delay</li>
<li>Packet       loss – usually caused by sudden burst or failures</li>
</ul>
</li>
<li>Available      bandwidth
<ul>
<li>Maximum       bandwidth of a path is equal to the bw of the link with the       lowest/smallest bw</li>
<li>Available       bandwidth = MaxBW/Number of Flows</li>
<li>Possible       remedies include:
<ul>
<li>Increase        link bandwidth – not always beneficial for bursty traffic</li>
<li>Classify        and mark traffic</li>
<li>Deploy        queuing mechanisms</li>
<li>Use        compression techniques
<ul>
<li>Link         compression</li>
<li>TCP         header compression</li>
<li>RTP         header compression<span id="more-128"></span></li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
<li>End-to-end      delay
<ul>
<li>4       types of end-to-end delay
<ul>
<li>Processing        – the time it takes for a device to perform all tasks necessary to move        packet from ingress interface to egress interface</li>
<li>Queuing        – time that the packet spends in the output queue</li>
<li>Serialization        – time it takes to put the bits of frame on the wire</li>
<li>Propagation        – time it takes for the frame to cross the physical link</li>
</ul>
</li>
</ul>
</li>
<li>Jitter/Delay      Variation
<ul>
<li>For       voice and video, packets must be released to the application in the       correct order and same rate at which they were released at the source</li>
<li>De-jitter       buffer compensates for the delay variation using the RTP time stamp on       the packets</li>
<li>5       ways of compensating for jitter
<ul>
<li>Increase        link bandwidth</li>
<li>Prioritize        delay-sensitive packets and forward important packets first</li>
<li>Re-prioritize        packets – usually when a packet leaves a domain</li>
<li>L2        payload compression – reduces size of IP packet</li>
<li>Use        header compression – cRTP – improves the overhead to payload ratio</li>
</ul>
</li>
</ul>
</li>
<li>Packet      Loss
<ul>
<li>Occurs       when buffer space is exhausted (output queue) and device ends up dropping       incoming packets</li>
<li>Interface       resets may cause packet loss as well</li>
<li>Fragile       flows – application flows that don’t use TCP and are more drop sensitive</li>
<li>Use       <strong>show interface </strong>command to show       interface counters
<ul>
<li>Output        drop – number of packets dropped because the output queue was full (aka        tail drop)</li>
<li>Input        queue drop – CPU may be over utilized or input buffer is full</li>
<li>Ignore        – total number of frames ignored due to lack of buffer space</li>
<li>Overrun        – shows number of packets dropped when CPU is too busy to allocate        buffer space to incoming packets</li>
<li>Frame        Error – frames with CRC errors, runts, or giants</li>
</ul>
</li>
<li>Methods       for guarding against packet loss include
<ul>
<li>Increase        link bandwidth – results in faster packet departures from interfaces</li>
<li>Increase        buffer space – large buffer space allows better handling of bursty        traffic</li>
<li>Provide        guaranteed bandwidth – CBWFQ and LLQ can reserve bandwidth for specific        traffic classes</li>
<li>Perform        congestion avoidance – RED and WRED can drop packets before queue fills        up
<ul>
<li>Packets         can be dropped from specific flows whereas tail drop will drop all         packets</li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>
<h4>Definition of QoS and Three Steps to Implementing It</h4>
<p>“QoS is the ability of the network to provide better or special service to a set of users or applications (or both) to the detriment of other users, applications, or both”</p>
<ul>
<li>RTP      priority queue ensures voice packets are given the right of way (protects      voice from data)</li>
<li>Strict      priority queue (in LLQ) limits the bw of the priority queue (protects data      from voice)</li>
<li>Call      admission control – prevents voice calls from saturating the link      (prevents them from going beyond a specified limit)</li>
</ul>
<p><strong>Three steps to implement QoS</strong></p>
<ol>
<li>Identify      traffic types and their requirements</li>
<li>Classify      traffic based on the above requirements</li>
<li>Define      policies for each traffic class</li>
</ol>
<h5>Step 1: Identify Traffic Types and Their Requirements</h5>
<ul>
<li>Perform      a network audit
<ul>
<li>Run       audit during the busiest time of day but also at other times as well</li>
</ul>
</li>
<li>Perform      a business audit and determine each application’s importance
<ul>
<li>Consider       whether delaying or dropping packets of each application is acceptable</li>
</ul>
</li>
<li>Define      appropriate service levels for each class of traffic</li>
</ul>
<h5>Step 2: Classifying Traffic Based on the Requirements Identified</h5>
<ul>
<li>The      defined classes must be in line with business objectives</li>
<li>Traffic/applications      in the same class must have common requirements</li>
<li>VoIP      traffic is usually given its own class</li>
<li>Different      classes as defined by many case studies include:
<ul>
<li>VoIP       – delay and drop is to be minimized
<ul>
<li>Packet        loss &lt; 1%</li>
<li>End-to-end        delay of 150ms</li>
</ul>
</li>
<li>Mission-critical
<ul>
<li>Critical        business applications</li>
</ul>
</li>
<li>Signaling       traffic
<ul>
<li>Usually        its own class</li>
<li>Minimum        bandwidth expectations</li>
</ul>
</li>
<li>Transactional       applications
<ul>
<li>Database        driven apps</li>
</ul>
</li>
<li>Best       effort
<ul>
<li>All        unidentified traffic</li>
</ul>
</li>
<li>Scavenger
<ul>
<li>All        traffic that is to be classified lower than best effort (p2p traffic for        example)</li>
</ul>
</li>
</ul>
</li>
</ul>
<h5>Step 3: Defining Policies for Each Class</h5>
<ul>
<li>Set a      max bandwidth limit for each class</li>
<li>Set a      min bandwidth guarantee for each class</li>
<li>Assign      a relative priority level</li>
<li>Apply      congestion management, avoidance, and other QoS techniques to a class</li>
</ul>
<h3>Identifying and Comparing QoS Models</h3>
<h4>Best effort</h4>
<ul>
<li>Pros
<ul>
<li>Easily       scalable</li>
<li>Ease       of implementation – none!</li>
</ul>
</li>
<li>Cons
<ul>
<li>Lack       of service guarantee</li>
<li>Lack       of service differentiation</li>
</ul>
</li>
</ul>
<h4>Integrated Services Model (IntServ) <a title="RFC 1633" href="http://www.ietf.org/rfc/rfc1633.txt" target="_blank">[RFC 1633</a>]</h4>
<ul>
<li>Pros<strong> </strong>
<ul>
<li>Explicit       end-to-end resource admission control<strong> </strong></li>
<li>Per-request       policy admission control<strong> </strong></li>
<li>Signaling       of dynamic port numbers<strong> </strong></li>
</ul>
</li>
<li>Cons<strong> </strong>
<ul>
<li>Each       flow has continuous signaling resulting in lots of overhead as the number       of flows increased<strong> </strong></li>
<li>Hard       to scale because each flow is tracked and maintained<strong> </strong></li>
</ul>
</li>
<li>Often      called Hard QoS</li>
<li>Based      on explicit signaling and managing/reserving network resources</li>
<li>Guarantees      bandwidth, delay, and packet loss – predictable service level</li>
<li>Uses      RSVP (resource reservation protocol) – RSVP travels the network and      requests bandwidth for the application flow
<ul>
<li>If       RSVP succeeds, the application can begin operating</li>
<li>If       RSVP fails the app cannot begin operating</li>
</ul>
</li>
<li>Mimics      the PSTN model</li>
<li>In      addition to RSPV, enable the following:
<ul>
<li>Admission       control – if resources cannot be made available, the application is       denied</li>
<li>Classification       – traffic belonging to an application that has made resource reservations       must be classified and recognized by transit routers</li>
<li>Policing       – measure and monitor applications to ensure they do not exceed resource       usage above their profiles</li>
<li>Queuing</li>
<li>Scheduling       – works in conjunction with queuing – this is the relative attention each       queue gets if multiple queues are configured – referred to as the       scheduling algorithm</li>
</ul>
</li>
</ul>
<h4>Differentiated Services Model (DiffServ) [RFC <a title="RFC 2474" href="http://www.ietf.org/rfc/rfc2474.txt" target="_blank">2474 </a><a title="RFC 2475" href="http://www.ietf.org/rfc/rfc2475.txt" target="_blank">2475</a>]</h4>
<ul>
<li>Pros
<ul>
<li>Highly       scalable – able to handle 1000’s of flows</li>
<li>Flexible       framework to define as many service levels as business demands dictate</li>
</ul>
</li>
<li>Cons
<ul>
<li>Does       not provide an <strong><em>absolute </em></strong>guarantee of service</li>
<li>Somewhat       complex to configure across many devices</li>
</ul>
</li>
<li>Based      on a per-hop behavior – does not require signaling like IntServ
<ul>
<li>Each       device in the network must be programmed to provide a specific level of       service for each class of traffic</li>
</ul>
</li>
<li>Network      traffic is classified</li>
<li>QoS      policies enforce differentiated treatment of defined classes</li>
<li>Classes      and policies are based on business requirements</li>
<li>Often      called Soft QoS</li>
</ul>
<h3>QoS Implementation Methods</h3>
<h4>Legacy command line</h4>
<ul>
<li>Difficult      to maintain consistency across many devices</li>
<li>Error      prone</li>
<li>Does      not completely separate classification from policy definition</li>
</ul>
<h4>Modular QoS CLI (MQC)</h4>
<ul>
<li>Traffic      classification and policy definition are done separately<strong> </strong>
<ul>
<li>Policies       are defined after classes are defined<strong> </strong></li>
<li>Different       policies might reference the same classes<strong> </strong></li>
</ul>
</li>
<li>Greater      consistency across devices<strong> </strong></li>
</ul>
<p><strong> </strong></p>
<p><strong>Implementing QoS with MQC – 3 Major Steps</strong></p>
<ol>
<li>Define traffic using the <strong>class-map</strong> command (Case sensitive)
<ol>
<li>Divides identified traffic into a number of named classes</li>
</ol>
</li>
<li>Define QoS policies for traffic classes using <strong>policy-map </strong>(Case sensitive)
<ol>
<li>Defines the treatment of defined classes from step 1</li>
<li>Can define QoS policies for up to 256 traffic classes</li>
</ol>
</li>
<li>Apply the policies in the inbound or outbound direction using the <strong>service-policy</strong> command
<ol>
<li>Defines where the policies are applied</li>
</ol>
</li>
</ol>
<p><code><strong><br />
class-map MyVoipMap<br />
match     access-group 100<br />
</strong></code></p>
<p><strong>match-any vs. match-all</strong></p>
<ul>
<li>In order to bind the packet to the class
<ul>
<li>Match-any &#8211; Only one access-list entry needs to be matched</li>
<li>Match-all &#8211; All entries in an access-list must be matched</li>
</ul>
</li>
</ul>
<p><code><strong>policy-map MyPolicyMap ! defines a policy map<br />
class MyVoipMap !     associates MyVoipMap (above) with this policy<br />
priority 256 !     VOIP traffic has bandwidth guarantee of 256Kbps</code></p>
<p>class Business-Application<br />
bandwidth 256</p>
<p>class class-default ! Sets the queuing method for all unspecified traffic<br />
fair-queue</p>
<p>int s0/0<br />
service-policy output MyPolicyMap ! applies policy map defined above to this interface<br />
</strong></code></p>
<h4>AutoQoS</h4>
<ul>
<li>Analyzes network traffic for as long as you let it run</li>
<li>Generates traffic classes based on traffic it has processed (Auto QoS Discovery)</li>
<li>Generates policy maps based on the classes it has defined</li>
<li>Applies the appropriate policies to an interface</li>
<li>Simplifies task of QoS configuration</li>
<li>Prerequisites include:
<ul>
<li>Enable CEF</li>
<li>Enable NBAR</li>
<li>Verify that the correct bandwidth is configured on the interface</li>
</ul>
</li>
</ul>
<p><strong>Related AutoQoS Commands</strong></p>
<ul>
<li><strong>auto qos voip</strong> - first generation of auto QoS – automated generation of QoS commands to get the device ready for voice over IP</li>
<li><strong>auto discovery qos </strong>– must be enabled for the router to discover and analyze network traffic entering the interface using NBAR</li>
<li><strong>auto qos </strong>– router builds class maps based on discovery and applies a policy map on the interface</li>
</ul>
<h4>SDM QoS Wizard</h4>
<p>Step 1: Click <strong>Configure</strong><br />
Step 2: Click <strong>Quality of Service</strong><br />
Step 3: Click <strong>Create QoS Policy</strong><br />
Step 4: Click <strong>Launch QoS Wizard</strong></p>
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			<media:title type="html">Gerren</media:title>
		</media:content>
	</item>
		<item>
		<title>ONT &#8211; Introduction to VoIP</title>
		<link>http://ciscocertifiedhell.com/2009/06/30/ont-introduction-to-voip/</link>
		<comments>http://ciscocertifiedhell.com/2009/06/30/ont-introduction-to-voip/#comments</comments>
		<pubDate>Tue, 30 Jun 2009 12:23:18 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Exams]]></category>
		<category><![CDATA[642-845]]></category>
		<category><![CDATA[ONT]]></category>
		<category><![CDATA[VoIP]]></category>

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		<description><![CDATA[Also available as a PDF here Introduction to VoIP Networks Benefits of Packet Telephony More efficient bandwidth usage Lower transmission and network costs/expenses Improved productivity Access to new communication devices Packet Telephony Components Phones Gateways – Interconnect with other gateways and allow communication between devices that may not be accessible from the IP network. Also [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=79&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>Also available as a PDF <a title="Chapter 1 Notes" href="http://www.ciscocertifiedhell.com/wp-content/uploads/2009/06/642-845-notes-chapter-1.pdf" target="_blank">here</a></p>
<h3>Introduction to VoIP Networks</h3>
<h4>Benefits of Packet Telephony</h4>
<ul>
<li>More      efficient bandwidth usage</li>
<li>Lower      transmission and network costs/expenses</li>
<li>Improved      productivity</li>
<li>Access      to new communication devices</li>
</ul>
<h4>Packet Telephony Components</h4>
<ul>
<li>Phones</li>
<li>Gateways      – Interconnect with other gateways and allow communication between devices      that may not be accessible from the IP network. Also responsible for      connecting PBX’s to IP networks</li>
<li>Multipoint Control Units (MCU) – conference      calling device that combines the streams from participants and returns the      result to each participant</li>
<li>Application      &amp; Database Servers</li>
<li>Gatekeepers      – these provide call routing and call admission control (CAC) services.      Call routing resolves a name or number to an IP address. CAC grants      permission for a call setup</li>
<li>Call      Agents – handles call routing, address translation, and call setup</li>
<li>Video      End Points</li>
<li>Digital      Signal Processors – convert analog signals to digital signals using      different codes</li>
</ul>
<p><span id="more-79"></span></p>
<h4>Analog Interfaces</h4>
<ul>
<li>FXS (Foreign      Exchange Station) – Meant for analog phones, fax machines, and modems. To      these devices, the gateway acts like the PSTN CO switch</li>
<li>FXO (Foreign      Exchange Office) – Connects to a regular phone jack to be connected to the      PSTN</li>
<li>E&amp;M      – Ear and Mouth (or Earth and Magento) – Generally provide PBX to  PBX analog trunk connectivity</li>
</ul>
<h4>Digital Interfaces</h4>
<ul>
<li>Provides      connection to PSTN CO and PBX switches
<ul>
<li>BRI       or T1/E1 interface</li>
</ul>
</li>
<li>BRI      and PRI Interfaces use command channel signaling (CCS) – uses a dedicated      D (Delta) channel for signaling</li>
<li>T1’s      can be configured to use CAS – does not use a dedicated D channel (aka      “robbed bit signaling” because each CAS channel gives up a few bits to      perform signaling)</li>
</ul>
<h4>Stages of a Phone Call</h4>
<ul>
<li>Three      most popular VoIP signaling protocols are:
<ul>
<li>H.323       – ITU standard</li>
<li>Media       Gateway Control Protocol (MGCP) – IETF standard</li>
<li>Session       Initiation Protocol (SIP) – IETF standard</li>
</ul>
</li>
<li>Three      stages of a phone call
<ul>
<li>Call       setup</li>
<li>Call       maintenance</li>
<li>Call       teardown</li>
</ul>
</li>
<li>Call      Setup
<ul>
<li>Destination       telephone number must be resolved to an IP address
<ul>
<li>Call        request must be sent to this IP</li>
<li>Called        “call routing”</li>
</ul>
</li>
<li>Call       admission control (CAC) – determines if enough bandwidth is available
<ul>
<li>If        not enough bandwidth, CAC sends message to initiator advising of        insufficient resources (fast busy signal)</li>
</ul>
</li>
<li>If       call routing and CAC succeed, a call request is sent towards destination       IP</li>
<li>If       call is accepted, the following parameters are negotiated:
<ul>
<li>Source        and destination IP addresses to be used for the call</li>
<li>Source        and destination UDP ports that the <a href="http://www.ietf.org/rfc/rfc1889.txt">RTP</a> uses</li>
<li>Compression        algorithm</li>
</ul>
</li>
</ul>
</li>
<li>Call      Maintenance
<ul>
<li>Collects       statistics such as packets exchange, packets lost, delay, and jitter</li>
<li>End       points can analyze this data and can provide call quality info upon       request or they can send it to another device for analysis</li>
</ul>
</li>
<li>Call      Teardown
<ul>
<li>After       an end point terminates the call, the call teardown process sends the       appropriate notifications to all involved devices to free up resources</li>
</ul>
</li>
</ul>
<h4>Distributed vs. Centralized Call Control</h4>
<ul>
<li>Distributed      Model
<ul>
<li>Multiple       devices are involved in setup, maintenance, and teardown, and other       aspects of call control</li>
<li>H.323       and SIP are considered distributed call control protocols</li>
</ul>
</li>
<li>Centralized      Model
<ul>
<li>Relieves       the gateways and endpoints for being responsible for call control tasks</li>
<li>MGCP       end points not intelligent enough to perform call control tasks and must       rely on a CA (call agent)</li>
<li>Analog       voice digitization, encapsulation into IP, and transport still handled by       DSP of the MGCP gateways and end points (basically, the phones and       routers handle the “IP” part in “VoIP” – the CA handles the call control)</li>
<li>If       call is terminated, the CA is notified and advises endpoints to release       their resources</li>
<li>End       points can monitor call quality and notify the CA if quality is       unacceptable</li>
</ul>
</li>
</ul>
<h3>Digitizing and Packetizing Voice</h3>
<h4>Basic Voice Encoding: Converting Analog to Digital</h4>
<ul>
<li>Four      Major Steps
<ul>
<li>Sampling       – the periodic capture and recording of voice
<ul>
<li>Result        of sampling is called pulse amplitude modulation (PAM) signal</li>
</ul>
</li>
<li>Quantization       – the process of assigning numeric values to the amplitude of each sample       on the PAM signal</li>
<li>Encoding       – process of representing the quantization result for each PAM in binary</li>
<li>Compression       (Optional) – reduces the number of bits that must be transmitted per       second with the least possible amount of voice quality degradation       (always less than 64Kbps)</li>
</ul>
</li>
</ul>
<ul>
<li>Converting      Digital Back to Analog
<ul>
<li>Decompression</li>
<li>Decoding       and filtering</li>
<li>Reconstructing       analog signal</li>
</ul>
</li>
</ul>
<h4>The Nyquist Theorem</h4>
<ul>
<li>A      signal that is sampled at least 2x the highest frequency of that signal      yields enough samples for accurate reconstruction of the signal at the      receiving end</li>
</ul>
<h4>Quantization</h4>
<ul>
<li>The      process of assigning numeric values to the amplitude of each of the      samples on the PAM signal</li>
<li>Quantization      error (Quantization Noise)– The difference due to “rounding” between the      original signal and the signal received at the far end</li>
</ul>
<h4>Compression Bandwidth Requirements and Their Comparative Qualities</h4>
<ul>
<li>Several      ITU compression standards exist and differ based on the following:
<ul>
<li>Bandwidth       requirements</li>
<li>Quality       degradation they cause</li>
<li>Delay       they introduce</li>
<li>CPU       overheard due to complexity</li>
</ul>
</li>
<li>ITU      standard for measuring quality of voice codecs is mean opinion score (MOS)
<ul>
<li>Range       from 1 (worst) to 5 (best) (subjective)</li>
</ul>
</li>
</ul>
<h4>Digital Signal Processors</h4>
<ul>
<li>Provide      3 Major Services
<ul>
<li>Voice       termination</li>
<li>Transcoding       – (when 2 parties use different codecs, the DSP converts one codec into       the other)</li>
<li>Conferencing
<ul>
<li>If        all parties use same codec, it’s called a single-mode conference</li>
<li>If        parties use different codes, it’s called mixed-mode conference
<ul>
<li>The         DSP must perform transcoding in this case</li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>
<h3>Encapsulating Voice Packets</h3>
<h4>Real-time Transport Protocol</h4>
<ul>
<li>Uses      RTP (real-time transport protocol)
<ul>
<li>Runs       over UDP on ports 16,384 to 32,767</li>
<li>Adds       timestamps to the packets at the source, so that they can be replayed at       the same rate as when it left the source</li>
<li>Also       uses sequence numbers, reordering, and reassembly</li>
</ul>
</li>
<li>VoIP      Packets have the following headers
<ul>
<li>IP @       20 bytes</li>
<li>UDP       @ 8 bytes</li>
<li>RTP       @ 12 bytes</li>
<li><strong>Total: </strong>40 bytes (of headers       alone)<strong> </strong></li>
</ul>
</li>
<li>DSP      usually puts10ms of voice in one package, and puts 2 packages in an IP      packet</li>
<li>Resulting      packet size depends on the codec used</li>
</ul>
<h4>Reducing Header Overhead</h4>
<ul>
<li>Compressed      RTP (cRTP) aka RTP Header Compression</li>
<li>cRTP      must be applied on both sides of a link</li>
<li>Sender      and receive agree on a hash value for the 40 bytes of header data and only      send the hash value once computed</li>
<li>If      cRTP doesn’t account for the header checksum (UDP checksum) the headers      are reduce to 2 bytes
<ul>
<li>If       it considers the UDP checksum, the headers are reduce to 4 bytes</li>
</ul>
</li>
<li>cRTP      recommend for slow links only (less than 2Mb bandwidth) – and only if      performed in hardware</li>
<li>cRTP      adds delay due to extra calculations needed</li>
</ul>
<h3>Bandwidth Calculations</h3>
<h4>Consider the following in addition to the codec used</h4>
<ul>
<li>Packet      rate and packetization size
<ul>
<li>Packet       rate in packets per second (pps) – inversely proportionate to       packetization size</li>
<li>Packetization       size – amount of voice in each IP packet (Number of 10ms samples)</li>
</ul>
</li>
<li>IP,      UDP, RTP header overhead</li>
<li>Layer      2 overhead</li>
<li>Tunneling      protocol overhead (GRE, IPSec, L2TP, etc.)</li>
</ul>
<h4>ITU Codec Standards</h4>
<ul>
<li>G.711      is PCM (pulse code modulation)
<ul>
<li>8000       samples per second</li>
<li>8       bits per sample</li>
<li>64,000       bits per second (64Kbps)</li>
<li>No       compression</li>
</ul>
</li>
<li>G.726      – Adaptive Differential Pulse Code Modulation
<ul>
<li>Sends       fewer bits per sample (instead of 8 per sample)</li>
<li>Bits       describe the change from previous sample</li>
<li>4       bits sent is G.726 r32 (32Kbps)</li>
<li>3       bits sent is G.726 r24 (24Kbps)</li>
<li>2       bits sent is G.726 r16 (16Kbps)</li>
</ul>
</li>
<li>G.722      – Wideband Speech Encoding Standard
<ul>
<li>Divides       signal into 2 sub-bands</li>
<li>Encodes       each sub-band using a modified ADPCM</li>
<li>Bit       rates of 64Kbps, 56Kbps, or 48Kbps</li>
</ul>
</li>
<li>G.727      – Low Delay Exited Linear Prediction
<ul>
<li>Wave       shapes of five samples are expressed with 10 bit codes</li>
<li>16Kbps</li>
</ul>
</li>
<li>G.729      – Conjugate Structure Algebraic Code Exited Linear Prediction
<ul>
<li>Similar       to G.727 but uses 10 samples</li>
<li>8Kbps</li>
</ul>
</li>
</ul>
<h4>Data Link Overhead (L2)</h4>
<ul>
<li>Each      L2 technology adds overhead to the overall packet
<ul>
<li>Ethernet       – 18 bytes</li>
<li>Frame       Relay – 6 bytes</li>
<li>Multilink       PPP – 6 bytes</li>
<li>Dot1Q       – 22 bytes</li>
</ul>
</li>
<li>L2      overhead must be considered when calculating total bandwidth for a VoIP      call</li>
</ul>
<h4>Security and Tunneling Overhead</h4>
<ul>
<li>IPSec      in tunnel mode adds another 20 byte header
<ul>
<li>Original       IP packet is encrypted within another IP packet</li>
</ul>
</li>
<li>IPSec      also adds additional delay due to time taken to decrypt packets</li>
<li>Must      also consider other tunneling protocols for BW calculation</li>
</ul>
<h4>Six Major Steps for Calculating the Total Bandwidth for a VoIP Call</h4>
<ol>
<li>Determine      the codec and packetization period</li>
<li>Determine      the link-specific information
<ul>
<li>Is       cRTP being used</li>
<li>Type       of L2 encapsulation</li>
<li>Security       or tunneling protocols in use</li>
</ul>
</li>
<li>Calculate      the packetization size (size of the voice payload)
<ul>
<li>(Codec       bw in bits x Packetization Period in seconds) / 8 = size of voice payload       in bytes)
<ul>
<li>NOTE:        Packetization period usually given in ms – must divide by 1000 to arrive        at seconds</li>
</ul>
</li>
</ul>
</li>
<li>Calculate      the total frame size
<ul>
<li>Consider       all overhead involved (L2, security, tunneling, etc.)</li>
</ul>
</li>
<li>Calculate      the packet rate
<ul>
<li>Packet       rate = 1 / Packetization period in seconds</li>
</ul>
</li>
<li>Calculate      total bandwidth
<ul>
<li>Multiply       frame size from step 4 (in bits) x packet rate from step 5 = total       bandwidth</li>
<li>Example:       Frame size of 66 bytes x 50 pps = 528 bits x 50 = 26,400 bits or 26.4Kbps</li>
</ul>
</li>
</ol>
<ul>
<li>VAD      – saves bandwidth by detecting silence and 1 way audio (Such as music on      hold – data only flows in 1 direction)
<ul>
<li>Dependent       on:
<ul>
<li>Type        of audio</li>
<li>Background        noise level</li>
<li>Other        factors such as differences in language and culture</li>
</ul>
</li>
<li>Can       save up to 35% of bandwidth</li>
<li>Heavily       depended on above factors – most bw estimates don’t take VAD into       consideration</li>
</ul>
</li>
</ul>
<h3>Implementing VoIP Support in an Enterprise Network</h3>
<h4>Main components consist of:</h4>
<ul>
<li>Gateway      – provide connectivity between analog, digital, and IP devices</li>
<li>Gatekeeper      – H.323 device that provides call routing or CAC</li>
<li>CUCM      – acts as IP PBX</li>
<li>IP      Phones</li>
</ul>
<h4>SRST – survivable remote site telephony</h4>
<ul>
<li>If      WAN or other link to call manager goes down, an SRST enabled device can      route those calls over the PSTN</li>
<li>Provides      intra-office calling, hold, and transfer</li>
</ul>
<h4>Cisco Unified Call Manager Functions</h4>
<ul>
<li>Cisco      Call Manager  is call processing      software and is the main component of CUCM
<ul>
<li>Supports       MGCP, H.323, SIP, and SCCP IP signaling</li>
</ul>
</li>
<li>Provides      the following services
<ul>
<li>Call       processing</li>
<li>Dial       plan administration</li>
<li>Signaling       and device control</li>
<li>Phone       feature administration</li>
<li>Directory       and XML services</li>
<li>Programming       interface to external applications</li>
</ul>
</li>
</ul>
<h4>Deployment Models</h4>
<ul>
<li>Single      site</li>
<li>Multisite      with centralized call processing
<ul>
<li>CUCM       placed at main site</li>
<li>All       IP devices are under control of CUCM at main site</li>
<li>DSP       resources can be distributed</li>
<li>Signaling       and call control go through main site, but intra-site calls stay local       (the actual voice traffic)</li>
<li>Each       site has PSTN connection</li>
<li>CAC       can deny calls if WAN link is saturated
<ul>
<li>Can        reroute those calls through PSTN if needed</li>
</ul>
</li>
</ul>
</li>
<li>If WAN is down, SRST can reroute calls over PSTN</li>
<li>Multisite      with distributed call processing
<ul>
<li>Each       site has its own CUCM</li>
<li>All       intrasite traffic including call control stays at local site</li>
</ul>
</li>
<li>Clustering      over WAN
<ul>
<li>Servers       in a cluster dispersed throughout various sites</li>
<li>Servers       need to communicate over the WAN for database synch and replication</li>
<li>Maximum       RTT between sites must be &lt; 40ms</li>
</ul>
</li>
</ul>
<h4>Identifying Voice Commands in IOS Configurations</h4>
<ul>
<li>Terminology:
<ul>
<li>Dial       peer: IOS configuration that links/binds a telephone number to a local       POTS interface (FXS) or a remote IP
<ul>
<li>One        POTS dial peer and one VoIP dial peer exist</li>
</ul>
</li>
</ul>
</li>
</ul>
<p><strong>Example </strong>(R1 and R2 are connected over an IP network)</p>
<p><strong>R1 Configuration</strong><br />
Dial-peer voice 1 pots ! configure dial-peer 1 as POTS<br />
destination-pattern 11 ! set the dial pattern<br />
port 1/1/1 ! device is on port 1/1/1 (FXS)</p>
<p>Dial-peer voice 2 voip<br />
destination-pattern 22<br />
session target ipv4: 192.168.2.2</p>
<p><strong>R2 Configuration</strong><br />
Dial-peer voice 1 pots<br />
destination-pattern 22<br />
port 2/0/0</p>
<p>Dial-peer voice 2 voip<br />
destination-pattern 11<br />
session target ipv4: 192.168.1.1</p>
<h4>Call Admission Control (CAC)</h4>
<ul>
<li>Limits      the number of concurrent calls</li>
<li>Compliments      QoS configurations</li>
<li>Prevents      oversubscription of the WAN by VoIP calls</li>
</ul>
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		<title>ONT Study Plan</title>
		<link>http://ciscocertifiedhell.com/2009/06/29/ont-study-plan/</link>
		<comments>http://ciscocertifiedhell.com/2009/06/29/ont-study-plan/#comments</comments>
		<pubDate>Mon, 29 Jun 2009 15:08:03 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Exams]]></category>
		<category><![CDATA[642-845]]></category>
		<category><![CDATA[ONT]]></category>
		<category><![CDATA[Study Techniques]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=74</guid>
		<description><![CDATA[I think that in an effort to do better on the ONT exam, I&#8217;ll do some documentation via posts in hopes that it will sink in with me more effectively. I&#8217;d like to do a chapter by chapter breakdown using the OECG to start. Maybe like a &#8220;terminology&#8221; type section, &#8220;related protocols&#8221; section, configuration notes, [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=74&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>I think that in an effort to do better on the ONT exam, I&#8217;ll do some documentation via posts in hopes that it will sink in with me more effectively. I&#8217;d like to do a chapter by chapter breakdown using the OECG to start. Maybe like a &#8220;terminology&#8221; type section, &#8220;related protocols&#8221; section, configuration notes, and some &#8220;gotchas.&#8221; Sounds a bit cheesy though&#8230;we&#8217;ll see what pans out.</p>
<p>Stay tuned&#8230;</p>
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		<title>ISCW Passed!</title>
		<link>http://ciscocertifiedhell.com/2009/06/27/iscw-passed/</link>
		<comments>http://ciscocertifiedhell.com/2009/06/27/iscw-passed/#comments</comments>
		<pubDate>Sat, 27 Jun 2009 16:54:51 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Exams]]></category>
		<category><![CDATA[ISCW]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=62</guid>
		<description><![CDATA[wOOt. I passed the ISCW today&#8230;not a top-of-the-class kind of score, but passing nonetheless. I&#8217;m not generally an overachiever, but I thought I would do better than I did.  Don&#8217;t get me wrong, I&#8217;m happy that I passed, but either way&#8230;I still would&#8217;ve enjoyed a higher score. I think that I get caught in up [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=62&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>wOOt. I passed the ISCW today&#8230;not a top-of-the-class kind of score, but passing nonetheless. I&#8217;m not generally an overachiever, but I thought I would do better than I did.  Don&#8217;t get me wrong, I&#8217;m happy that I passed, but either way&#8230;I still would&#8217;ve enjoyed a higher score.</p>
<p>I think that I get caught in up in the people that are posting that they &#8220;Got 1000/1000&#8243; &#8212; I suppose that there are folks out there that can ace these tests without much effort, but I&#8217; guessing that a lot of people I see posting these kind of messages are brain-dumpers. No disrespect to anyone who has aced a Cisco exam without using dumps of course.</p>
<p>I supposes that I should be proud that I can pass without using dumps, but I would still like to improve my score next tie. Ahhh&#8230;oh well, who cares! 3 test down and only ONT to go for my CCNP.</p>
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		<title>ISCW Performance Anxiety</title>
		<link>http://ciscocertifiedhell.com/2009/06/26/iscw-performance-anxiety/</link>
		<comments>http://ciscocertifiedhell.com/2009/06/26/iscw-performance-anxiety/#comments</comments>
		<pubDate>Fri, 26 Jun 2009 19:13:03 +0000</pubDate>
		<dc:creator>Gerren</dc:creator>
				<category><![CDATA[Test Taking Strategy]]></category>
		<category><![CDATA[ISCW]]></category>
		<category><![CDATA[Testing]]></category>

		<guid isPermaLink="false">http://www.ciscocertifiedhell.com/?p=54</guid>
		<description><![CDATA[Here&#8217;s what I dislike about Cisco exams. You study, and study, and from your experience and past exams, you feel confident that you are ready to tackle that next exam. Exam day rolls around and about halfway through the exam, you realize that you mos definitely were not prepared. I&#8217;ve had that happen twice now, [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=ciscocertifiedhell.com&blog=9477841&post=54&subd=ciscocertifiedhell&ref=&feed=1" />]]></description>
			<content:encoded><![CDATA[<p>Here&#8217;s what I dislike about Cisco exams. You study, and study, and from your experience and past exams, you feel confident that you are ready to tackle that next exam. Exam day rolls around and about halfway through the exam, you realize that you mos definitely were not prepared.</p>
<p>I&#8217;ve had that happen twice now, and I&#8217;m not sure what the issue is. So, I&#8217;m scheduled to take the ISCW tomorrow, and feel very confident on for this exam, but the anxiety of getting there and realizing a few minutes into it that I&#8217;m not as ready as I thought, is always frustrating. Very, very frustrating.</p>
<p>Does this happen to anyone else, or is it just me? I know my weak points are as follows:</p>
<ul>
<li>PPPoA/E configuration commands</li>
<li>Some of the IPSec smaller details</li>
<li>Some parts of AAA, but I&#8217;m not sure what!?!</li>
</ul>
<p>So, I&#8217;ll be running through those questions/topics again tonight, and then tomorrow at 1000 is judgement day. If I pass this, it will be 3 down and ONT to go!</p>
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