CCENT BootCamp-Comment/Feedback/Suggestion by a Volunteer of DNS 3

CCENT - Career Certifications & Paths - Cisco Systems
Comment/Feedback/Suggestion by a Volunteer of DNS 3.....

CCENT Bootcamp-

It's really a very much good program that done by respected lectures...We as a student from DNS 3 July 09F, Would like to take this opportunity to thank all of you who worked hard for this camp to make sure we pass the exam....

Unfortunately not most who was able to fulfill the promise, but we promise the next time will be a record.

It's a situation that cannot be blamed anyone, we should blame our self for our failures.

About this camp we can hope about 20 percent.....the other it's in our hand, So now we all are gonna go to gain an priceless knowledge of working experience...
So just use the free time of yours to just go through the given notes and VCE files.....And mastered those two Cisco Discoveries...

And i planned to retake the CCENT exam on our LI time, Expecting that the coming DN3 student's camp starts after April 29th.....and hope that we all can participate and complete our unfinished business and promise.....

I heard that the coming DNS will be sit for a exam and those who pass will the chosen to sot for the CCENT....i think you guys can understand how lucky we are given a chance....To sit for this Professional Certificate......

Those who still don't understand or know nothing about this professional certificate please wake up from your dream and ask someone who knows the value of it...even you can ask your DAD/MOM......So put your ego a side and start to explore about this....

*Please wake up now and start searching...guys this life is fulfill of treasures you who need to find it with clues that given......Don't regret after...The one who saying this not your age...i hope you guys understand what I'm trying to say....

TIPS:

+If can go for any book stores look for CCENT books - if you ask me you can find it at KINOKUNIYA KLCC Surya, i brought for RM3++.....
+Surf Online for CCENT questions and print out and try to do it by your self.
+Study back all the materials that given in CCNET Boot Camp-That 9tut folder and some more.
+Study back all those two CISCO DISCOVERY.

And by here i would like to wish Ahmad Musyeriey for the success.
Those who didn't achieve this time we will try again...Next time the unbreakable record is ours...

So god bless you and good luck for the practical training and thanks for the respected lectures to give us this priceless chance.

*We really will appreciate if the camp period increased to at least one week. And no slots at night, because that's the time for us to recall back all the learned stuff.

Thanks.

From,
Volunteer Of DNS 3.
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How to create your own Cat 5 patch cables

Networking cables are a dime a dozen. You can get them just about anywhere…in standard sizes. But what happens when you need an odd size or you simply follow the beat of a DIY drum? In those cases you will want to know just how to make your very own Cat 5 Ethernet cables. And whether you need straight-through or crossover cables, TechRepublic has you covered.

In this article I am going to show you how to create both straight-through and cross over network cables.

What you will need

• Cat 5 cable
• RJ 45 Crimping tool
• RJ 45 Connectors
• Wire cutters (Leatherman-like multi-tool is ideal because it also has a knife that you might need)
• Cable Tester

Preparing the cable

The very first thing you need to do is to cut the cable to length. Once you have the cable cut to length, you will want to remove enough of the outer casing on each end to expose the inner wires so you can work. You will want to remove about an inch of the casing at each end. To do this I like to use a knife and very lightly score the outer case and then bend the wire at the score so the casing breaks. The casing should then peel right off the wire.

After you peel the casing off, separate the individual wires. You might have to cut away any insulation that is surrounding or between the inner wires. Once you have the wires separated you will want to make sure those wires are as straight as possible to make alignment and insertion into the RJ 45 connector simple.

Aligning the wires

Now comes the part that usually trips new users up. You have to make sure the color-coded wires are in the right order. First I will show you the order for a straight-through cable. A straight-through cable is a standard Ethernet cable. If you take a look at Figure A you will see the order you should use for straight-through ends.

Figure A

Both ends should be color-coded exactly like you see here.

Now, let’s say you want to create a crossover cable. To do this you will create one end exactly as you see in Figure A and then the other end will be color-coded according to what you see in Figure B.

Figure B

Make sure your color-coding is exactly as you see above on ONE end for a cross over cable.

Attaching the connectors

This is another point of confusion. Pin 1 on the RJ 45 connectors is on the left side of the connector when the clip is on the bottom side. If you are looking at the connector from the top and the clip is on the top side then Pin 1 is on the right side of the connector.

The first thing you need to do is very carefully line the wires up, side by side, in the correct order and then, using the cutting blade on your crimping tool, cut the very ends of the wires off so the edges all line up. After you have that done, carefully slide the wires into the connector, paying close attention that they remain in the correct order.

Once the wires are pushed all the way into the connector slide the connector into the crimping tool (there is only one place the RJ 45 will go into the crimper - see Figure C) and crimp the connector. Take the connected end off and give it a tug to make sure the crimp took.

Figure C

A solid crimp will keep you from having a poor connection later on, but don’t crush the connector.

When one end is complete, repeat the process on the other end, paying attention to whether the cable is either a straight-through or crossover.

Testing the connection

Although you can always just plug the cable into its destination jacks to test, it is always better practice to use a cable tester to make sure the connections you just created work properly. This is always a must if you are creating a number of cables or you are creating cables that will then be deployed to a remote location. The directions for testing will be specific to the tester you own. Make sure, if you are testing a cross over, that you know exactly how to test for this cable before you assume everything to be good to go.

Final thoughts

Making your own Ethernet cables can, in the long run, save you money as well as allow you to make cables in non-standard sizes. And now, when you have the need, you can work your own personal magic on Cat 5 cable so you can have as many different patch cables as you need.

Some interesting twists about Ethernet cabling

Differential signaling

To understand why Ethernet cable is built the way it is, it requires familiarity with how the signals are transmitted over the wires. The fancy term is differential signaling. During a digital pulse, each wire in the pair carries a signal that is the same voltage, but opposite polarity. The slide below (courtesy of Wikipedia) exemplifies the process:

The greater the difference between the input pulses, the larger the output pulse, making it easier for the receiver logic to differentiate ones and zeros. I might add that this becomes more important as throughput rates increase.

As you can see in the slide, differential signaling has some noise-canceling capability, but not enough when it comes to Ethernet cabling. That’s because two types of interference come into play, electromagnetic radiation from sources such as power wires or crosstalk from other pairs in the same cable. Both introduce noise that reduces the differential. If there is enough noise, the receiver can misread what was sent.

It’s all about the twists

The Ethernet cabling most of us are familiar with consists of four pairs of wires, twisted together, and enclosed in a single insulating cover jacket. Those twists are a pain when making connections, but are there for a reason. Transmitting Ethernet signals over a cable that small would not be possible without them.

To understand the importance of twisting the wires requires learning about common-mode rejection. It seems that digital electronics connected with balanced lines, such as twisted pair Ethernet cabling are capable of rejecting noise, as long as the spurious emission is common to both leads in the twisted pair.

It might help to use an example. I mentioned crosstalk earlier. If pairs were not twisted in Ethernet cabling, it is entirely possible for two wires in adjacent pairs to be next to each other for the entire length of the cable. That could skew the results by adding cross talk to only one leg of the pairing.

If the wires in the pair were twisted, both wires in the pair would be affected the same. Then the receiver using common-mode rejection would be able to filter out the crosstalk interference.

Geek trivia alert: This phenomenon was discovered by Alexander Graham Bell. In fact, telegraph wires were the first twisted pair. The wires switched position on the pole after a certain distance (courtesy of Wikipedia):

Another twist

Ever notice that some of the twisted pairs are easier to un-ravel? There is a reason for that. If adjacent pairs have an equivalent twist rate or pitch, the same wires of each pair could be next to each other for the entire run, negating differential signaling. In order to prevent that, Ethernet cable manufacturers use different twist rates (courtesy of Wikipedia):

One last note, according to cabling best practices, pair wires should not be untwisted more than 13 mm. This comes into play when using punch-down blocks.

UTP versus STP

There are two types of Ethernet cabling, Unshielded Twisted Pair (UTP) and Shielded Twisted Pair (STP). Everything that I mentioned up until now, applies to both. STP cabling is used if there is an abnormal amount of electromagnetic interference. STP uses metal-foil shielding that directs any external noise to ground. The metal foil can surround each twisted pair (STP), all the twisted pairs S/UTP), or both (S/STP).

Some installation tips

Every time I work with cable installers, I bug them mercilessly, trying to learn what they consider important. Here are some of their pointers:

• For solid wire UTP, the minimum bend radius is eight times the outside diameter of the cable. Anything less affects the twist rate, reducing noise rejection.
• When installing long runs be careful not to stretch the cable, doing so could alter the twist rate, again reducing noise rejections.
• Due to the high frequency of digital transmissions, the phenomenon of skin effect comes into play. So be careful not to nick the copper wire.
• Make sure to use plenum-rated Ethernet cabling, if the run is located in a space that is used for air circulation.
• Run Ethernet cabling at least 15 cm from any high-voltage lines, 30 cm is better.
• If Ethernet cabling must cross a high-voltage line, do so at a 90 degree angle.

If I missed a tip you feel is important, please share it with the rest of us.

Final thoughts

As digital throughput rates keep increasing the margin for error decreases rapidly. Make sure to keep those pairs twisted.

Taken: Tech Republic