WEBVTT

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 In this video, I'm going to cover another
 topic from section one of the

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 routing and switching CCT exam, which
 is identify the cabling on Cisco

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 equipment. Once again, my name is Keith
 Bogart, and I will be your instructor

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 for this video session.

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 So what are we going to talk
 about in this session?

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 Well, I'm going to talk about
 three major things.

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 Under what circumstances would you need
 to identify the cabling on Cisco

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 equipment? What is some common network
 cabling that you will run across?

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 And what are some of the major differences
 between copper and fiber optic

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 cables? So under what circumstances
 would you need to identify cables?

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 Well, there's several
 different situations.

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 Number one, maybe you're asked to go
 find a replacement ethernet cable

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 or something. Well, you would need
 to know how to accomplish this.

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 There's more than one kind of ethernet
 cable and you need to be aware

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 of that. Or alternatively,
 serial cables.

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 You might have to go
 find a serial cable.

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 Serial cables come in lots
 of different form factors.

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 You need to know which one you want if
 you're asked to replace or purchase

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 one. Or there's always the option of
 replacing or purchasing some new

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 fiber optic cable.

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 Do you know which one is appropriate
 for the port adapter or interface

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 that you're connecting to?

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 These are all questions that hopefully
 you'll be able to answer by the

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 time you're done with
 this section.

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 So let's start at a very high level
 when it comes to cabling.

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 So cabling in general comes
 in two main categories.

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 You've got copper cabling and you've
 got fiber optic cabling.

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 So the shape of the receptacle that
 that cable is going to plug into is

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 going to give you a pretty good clue
 as to whether or not that interface

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 requires a fiber or a copper cable
 is going to plug into it.

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 For example, here we see RJ45.

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 RJ45 jacks always accept
 copper cables.

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 Here we see from the previous video the
 Cisco DB60 or 5-in-1 serial interface

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 also accepts copper cable.

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 As do we see here we see some coaxial
 interfaces that once again, accepts

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 copper cable. Now your typical G-Bix
 and your SFPs, those accept your

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 fiber optic cabling.

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 So just by looking at the interface you
 can tell which type of cable you're

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 going to have to procure.

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 Now let's spend a little bit of time
 first of all talking about copper

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 cabling and the various differences
 you'll see there.

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 So with copper cabling there's a lot
 of distinctive characteristics of

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 copper cable. For one thing they're a
 lot thicker than fiber optic cable.

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 That's one way you
 can identify them.

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 Also there's clearly copper
 inside the cable.

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 If you were to snip it with a wire cutter
 or something like that inside

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 you would see one or more
 strands of copper.

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 And that's being used to carry your
 electrical signaling back and forth

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 on that cable. And there's three primary
 uses of copper cabling when it

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 comes to carrying data,
 voice or video signals.

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 You're looking at Ethernet cables,
 coaxial cables and serial cables.

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 We're going to talk about all three
 of those in pretty good detail here

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 in this section.

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 So let's start by talking
 about Ethernet.

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 Maybe somebody says to you, hey I want
 you to go and find a replacement

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 Ethernet cable for me.

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 Well they're actually going to have
 to give you a little bit more detail

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 than that for you to satisfy
 that objective.

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 When Ethernet very first came out
 it came out using copper cabling.

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 So the original Ethernet was something
 on what's called thick net which

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 looked very similar
 to coaxial cabling.

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 The connector was a little bit different
 but it looked like coaxial cabling.

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 Then not too many years later Ethernet
 evolved over time to support copper

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 as well as fiber optic connectors.


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 So the main point I want to come across
 to you here is if somebody just

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 simply says to you, hey I need
 a replacement Ethernet cable.

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 Question number one you need to get
 answered is do they need a copper

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 or a fiber optic Ethernet cable.

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 Now let's say they want
 a copper Ethernet cable.

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 Okay next question you have to answer
 is do you want a coaxial cable?

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 Probably not. They'll probably tell you
 they want a twisted pair Ethernet

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 cable. What exactly
 is twisted pair?

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 Let's go into the details of that.


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 So twisted pair is just
 like it sounds.

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 If you break open or cut through a twisted
 pair Ethernet cable you will

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 see multiple pairs of wires are
 twisted around each other.

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 So the wires come in pairs with each
 every two wires in a single pair

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 forming an electrical current
 like you see here.

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 So it's a pair of copper cables that
 forms a complete electrical loop.

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 Now the pairs are twisted around themselves
 to prevent electromagnetic

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 interference. If we're talking about
 a 10 megabit or 100 megabit Ethernet

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 well you technically only need two pairs
 of wires or four wires in total.

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 Other flavors of Ethernet for example
 gigabit Ethernet can use either

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 four or even eight pairs of wires.


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 But the main point is in twisted pair
 those pairs of wires are actually

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 physically twisted
 around each other.

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 And you can see that right
 here in this picture.

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 As we cut open the outside of an Ethernet
 cable you can clearly see that

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 each pair of wires here is
 twisted around each other.

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 So that is right now four pairs
 of wires each having twists.

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 And twisted pair cabling typically is
 terminated with an RJ45 jack which

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 we saw in the previous slide.

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 So let's say somebody says okay yes I
 want you to get me an Ethernet cable.

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 I need to be copper and I
 need to be twisted pair.

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 Well at that point you're going to sound
 like you're an irritant but you

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 need even a little more information
 to be able to identify the specific

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 cable that person's looking for.

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 Because twisted pair Ethernet cabling
 comes in two general categories

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 or two different variants.

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 The first is what's called
 straight through cable.

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 So straight through cable we
 can see it here on the left.

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 It's identified where if you hold up
 your RJ45 ends together each pin

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 corresponds to the same color as that
 same corresponding pin on the other

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 end of the cable.

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 So for example pin one if it's brown
 and white it'll be brown and white

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 pin one on the other side.

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 Pin four if it's blue well pin four
 on the other side will also be blue.

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 That is considered a straight through
 cable if it looks like that.

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 Straight through cables are used to
 connect devices together that reside

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 at different layers
 of the OSI model.

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 For example a PC or laptop is considered
 a layer three device just like

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 a router whereas a switch is considered
 a layer two device.

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 So if I was to connect a PC or
 laptop directly to a router.

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 So if I was to connect that I'm sorry
 a PC or laptop to a switch will

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 switch and a PCR devices are at different
 layers of the OSI model.

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 We've got a layer two device connecting
 to a layer three device.

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 In that particular case I'd be using
 a straight through cable to connect

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 them. The other variety of twisted pair
 cable for Ethernet is what's called

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 a crossover cable and you can clearly
 see that here that when you hold

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 those ends up next to each
 other pin one on one side.

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 One side goes to pin three on the other
 side and pin two on one side goes

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 to pin six on the other side.

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 So one to three two to six that is how
 a crossover cable is identified.

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 And when you want to connect devices
 together they're at the same layer

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 of the OSI model.

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 For example if I'm connecting two laptops
 directly back to back with an

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 Ethernet cable or two switches back to
 back with an Ethernet cable I would

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 use a crossover cable to do that.

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 Now a lot of devices these days have
 interfaces which are labeled auto

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 dash MDIX. That's a special type of interface
 that can automatically detect

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 the cable type and account for it.


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 So you don't really have to be that
 concerned if you're using straight

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 through or crossover.

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 But you should be aware that when it comes
 to twisted pair Ethernet cabling

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 it does come in two different flavors
 straight through and crossover.

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 Now even that might not be enough information
 because in addition to Ethernet

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 being straight through or crossover
 twisted pair also comes in different

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 categories. For example you may have
 heard of category five Ethernet or

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 category six Ethernet.

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 And what this means is that the higher
 the category the more twists per

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 centimeter you're going to have and the
 thicker the sheath thickness will

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 be this preventing electromagnetic
 interference.

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 So as the category gets higher those
 things change which means you can

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 have a higher speed on that cable.


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 For example take a
 look right here.

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 We've got category five compare the
 twists we have in that area with the

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 twists we would have in the same area
 in a category six clearly there

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 are more twists per inch or twists per
 centimeter in a category six than

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 a category five.

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 And the more twists you have the better that
 cable is at preventing electromagnetic

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 interference from one wire pair interfering
 with another wire pair.

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 Of course you're going to pay for that
 the higher the category of cable

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 the more expensive the
 category of cable.

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 And we also talked about the sheath
 thickness take a look at this here

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 we can see compare the category six
 with the category five you don't see

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 a lot of difference.

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 But the outside sheath is actually a
 little bit thicker on the category

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 six than the category five once again designed
 to help minimize electromagnetic

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 interference in this case from the outside
 world from penetrating those

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 wires within the cable.

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 And we're not done yet so even if you
 know that you need twisted pair

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 even if you know that you need category
 five or category six even if you're

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 told you need a straight
 through or a crossover.

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 Well if you're going to get really nitty
 gritty there's another variant

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 we have to consider with all of those
 things which is is the cable I'm

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 looking for shielded or unshielded
 and we can see those examples right

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 here. So most ethernet cables that you'll
 see that are like running along

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 the floor or running you know along the
 ceiling are what's called unshielded

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 twisted pair. The best way to describe
 unshielded twisted pair is actually

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 to contrast that against shielded twisted
 pair here in shielded twisted

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 pair every pair of wires is actually
 covered as you can see here with

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 sort of like an aluminum shielding
 which once again is even better at

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 preventing electromagnetic interference
 from both the outside world as

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 well as between the pairs
 of wires themselves.

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 Now this is going to cost you even
 more money to have shielded twisted

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 pair. Typically people would recommend
 putting shielded twisted pair when

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 you have cables running across areas that
 have high electromagnetic interference

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 such as running cables outdoors or
 maybe inside walls are going to be

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 right next to like high powered
 electrical lines.

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 And so if we bring it all together here
 you can see the different categories

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 the maximum lengths you can run you
 can see the higher the category the

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 higher the speed that you
 can run across that cable.

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 Now that's all talking about
 twisted pair cabling.

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 So what if I need a copper cabling
 that's not twisted pair what if the

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 particular port adapter or module I'm
 looking at actually uses coaxial

0:11:55.440000 --> 0:11:59.540000
 cabling. Well how would I identify coaxial
 cabling if you've never heard

0:11:59.540000 --> 0:12:00.840000
 that term before.

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 Well coaxial cabling looks like the typical
 cable that goes to your cable

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 TV. As you can see here it's basically
 got just a single wire it actually

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 it's a little misleading here it's not
 even though it looks like a single

0:12:13.900000 --> 0:12:15.580000
 wire right here just popping out.

0:12:15.580000 --> 0:12:20.160000
 That single wire which is the copper
 wire is actually surrounded by a

0:12:20.160000 --> 0:12:24.280000
 copper mesh. And this copper mesh is not
 only helping to prevent electromagnetic

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 interference that copper mesh is actually
 also transmitting electrical

0:12:29.380000 --> 0:12:34.100000
 signal just like this
 inner wire is doing.

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 Now coaxial cable is better at preventing
 electromagnetic interference

0:12:38.000000 --> 0:12:42.980000
 than twisted pair because it has this
 very thick insulation separating

0:12:42.980000 --> 0:12:47.200000
 the inner copper wire
 from the copper mesh.

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 So in that way it's better
 at preventing EMI.

0:12:49.200000 --> 0:12:51.880000
 Now it's more difficult to install
 than twisted pair because it's not

0:12:51.880000 --> 0:12:57.300000
 as bendable it's thicker less bendable
 than twisted pair cabling is.

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 Now the upside of this is in addition
 to being really good at preventing

0:13:02.780000 --> 0:13:08.800000
 EMI it can carry signals further a
 further distance than twisted pair

0:13:08.800000 --> 0:13:13.820000
 cabling. And you can see it uses a BNC
 connector so the connector is very

0:13:13.820000 --> 0:13:18.500000
 different. And usually when you're going
 to find coaxial cable and networking

0:13:18.500000 --> 0:13:21.960000
 is for cable modem connections that's
 where you're most likely going to

0:13:21.960000 --> 0:13:27.040000
 find it. Now what other types of cables
 might you be asked to identify?

0:13:27.040000 --> 0:13:30.560000
 Well you also need to know what console
 and auxiliary port cables look

0:13:30.560000 --> 0:13:37.400000
 like. Now console and aux ports typically
 have RJ45 connectors like we

0:13:37.400000 --> 0:13:42.300000
 see right here. But this RJ45 connector
 is not being used to carry Ethernet

0:13:42.300000 --> 0:13:46.680000
 signals. This is just being used
 strictly to carry ASCII data.

0:13:46.680000 --> 0:13:50.280000
 So the cable that connects to this is
 not going to be your typical Ethernet

0:13:50.280000 --> 0:13:54.040000
 cable. You're going to have what's
 called a rolled cable.

0:13:54.040000 --> 0:13:58.400000
 So the pin out in a rolled cable is
 actually like it says it's exactly

0:13:58.400000 --> 0:14:02.140000
 from one side it's opposite
 of the other side.

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 So for example if I have here light
 tan and white on pin number one that

0:14:07.860000 --> 0:14:12.160000
 will go over to the exact opposite pin
 or pin number eight on the other

0:14:12.160000 --> 0:14:16.360000
 side. Now let's hear pin number two
 will go all the way to the opposite

0:14:16.360000 --> 0:14:19.580000
 which is pin number seven
 on the opposite side.

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 So this is not for Ethernet signaling
 this is for console or aux ports.

0:14:24.180000 --> 0:14:30.240000
 And usually that will come the form
 factor of a flat blue cable.

0:14:30.240000 --> 0:14:35.480000
 And these will be using and in case
 you're wondering so on one end of

0:14:35.480000 --> 0:14:38.820000
 this console port cable you've
 got the RJ45 connector.

0:14:38.820000 --> 0:14:42.180000
 So that's connecting right
 here to the console port.

0:14:42.180000 --> 0:14:44.860000
 This right here is
 a DB9 connector.

0:14:44.860000 --> 0:14:50.880000
 Now maybe you're lucky enough to have a
 laptop that has a native DB9 interface

0:14:50.880000 --> 0:14:55.260000
 on it. If not which you probably don't
 have you'll probably need to get

0:14:55.260000 --> 0:15:01.640000
 a DB9 to USB converter or what's
 called a USB to serial converter.

0:15:01.640000 --> 0:15:06.700000
 So you can plug it into the
 USB port on your laptop.

0:15:06.700000 --> 0:15:10.580000
 So now let's go into the world of serial
 cables lots of different form

0:15:10.580000 --> 0:15:13.280000
 factors of serial cables.

0:15:13.280000 --> 0:15:19.220000
 Serial cables are another variant of
 a copper cable and many types exist.

0:15:19.220000 --> 0:15:22.360000
 You can see here lots of
 different form factors.

0:15:22.360000 --> 0:15:25.660000
 So if someone asks you hey I want you
 to get a replacement serial cable

0:15:25.660000 --> 0:15:30.540000
 from my router. Well there's three main
 questions you need to ask to make

0:15:30.540000 --> 0:15:32.260000
 sure you select the right one.

0:15:32.260000 --> 0:15:39.440000
 Number one is the router being connected
 to a DTE or a DCE device.

0:15:39.440000 --> 0:15:41.420000
 And here you can see what
 those acronyms stand for.

0:15:41.420000 --> 0:15:42.920000
 You need to know that.

0:15:42.920000 --> 0:15:47.980000
 Do you need a male or a female
 connector on the cable itself?

0:15:47.980000 --> 0:15:52.380000
 And what signaling standard
 does the device require?

0:15:52.380000 --> 0:15:55.240000
 Answers to these three questions will
 help you narrow down what specific

0:15:55.240000 --> 0:16:00.200000
 cable you need. Let's start
 talking about DTE or DCE.

0:16:00.200000 --> 0:16:04.260000
 So DTE you can see it's
 data terminal equipment.

0:16:04.260000 --> 0:16:09.320000
 Here's a little definition
 of what DTE is.

0:16:09.320000 --> 0:16:16.360000
 In case you've never seen a DSU CSU
 that is a box that looks like this.

0:16:16.360000 --> 0:16:22.000000
 And so the cable, so the DTE side of
 the cable will actually connect to

0:16:22.000000 --> 0:16:22.960000
 something like this.

0:16:22.960000 --> 0:16:26.480000
 Right? The DTE side of the cable will
 connect into your router or into

0:16:26.480000 --> 0:16:32.440000
 the CSU, DSU. Now some routers actually
 have a DSU CSU built right into

0:16:32.440000 --> 0:16:37.260000
 it directly. So clearly as we can see
 here on this side, this is not going

0:16:37.260000 --> 0:16:38.760000
 to accept a serial cable.

0:16:38.760000 --> 0:16:44.880000
 This is going to accept a twisted pair
 cable because using an RJ45 jack.

0:16:44.880000 --> 0:16:53.120000
 DCE data circuit terminating equipment
 is basically a device like a modem

0:16:53.120000 --> 0:16:57.260000
 that provides clocking to a DTE.

0:16:57.260000 --> 0:17:00.960000
 Most serial cables, if you hold them
 very closely to your eyeballs, one

0:17:00.960000 --> 0:17:04.200000
 side will actually
 be labeled as DTE.

0:17:04.200000 --> 0:17:07.040000
 One side will be labeled as DCE.

0:17:07.040000 --> 0:17:09.960000
 So you need to know which side of
 the cable are you plugging into?

0:17:09.960000 --> 0:17:12.260000
 Which device is the DCE?

0:17:12.260000 --> 0:17:18.180000
 Which device is the DTE so you can
 plug your cable in correctly?

0:17:18.180000 --> 0:17:21.220000
 And of course you need to know, do
 I need a male or a female connector

0:17:21.220000 --> 0:17:24.020000
 or male or female cable?

0:17:24.020000 --> 0:17:28.020000
 Here we have an example of a cable that
 has a male end on one and a female

0:17:28.020000 --> 0:17:29.400000
 end on the other.

0:17:29.400000 --> 0:17:34.540000
 Here's a cable where both ends are
 male and here's another cable where

0:17:34.540000 --> 0:17:36.680000
 both ends are female.

0:17:36.680000 --> 0:17:37.780000
 So you need to know that.

0:17:37.780000 --> 0:17:43.100000
 What kind of connectors do I
 need to plug my cable into?

0:17:43.100000 --> 0:17:45.440000
 And then lastly, what
 signaling standards?

0:17:45.440000 --> 0:17:49.120000
 So the signaling standards define things
 like what signals are going to

0:17:49.120000 --> 0:17:50.300000
 be used on that cable.

0:17:50.300000 --> 0:17:53.800000
 What are the pin outs that will
 be carrying those signals?

0:17:53.800000 --> 0:17:55.500000
 And what does the connector
 look like?

0:17:55.500000 --> 0:17:59.680000
 For example, here we see three examples
 of different signaling styles

0:17:59.680000 --> 0:18:02.560000
 or signaling protocols
 or signaling standards.

0:18:02.560000 --> 0:18:06.060000
 These are all three different
 serial cables.

0:18:06.060000 --> 0:18:09.180000
 And if you go to that URL there, you'll
 see there are lots and lots of

0:18:09.180000 --> 0:18:12.580000
 different serial cables
 that are supported.

0:18:12.580000 --> 0:18:16.600000
 So not only do you need to know, do
 I need a male or female cable, you

0:18:16.600000 --> 0:18:21.720000
 need to know what signaling standard the
 device supports so you can connect

0:18:21.720000 --> 0:18:24.480000
 the correct cable to it.

0:18:24.480000 --> 0:18:26.260000
 So enough of copper cable.

0:18:26.260000 --> 0:18:27.920000
 So that covers our copper cabling.


0:18:27.920000 --> 0:18:31.880000
 Let's move into the world of fiber
 optic cabling and talk a little bit

0:18:31.880000 --> 0:18:36.040000
 about that. So here we see
 fiber optic cabling.

0:18:36.040000 --> 0:18:39.380000
 And there's some distinctive characteristics
 of fiber optic.

0:18:39.380000 --> 0:18:43.980000
 Number one, fiber optic cables use
 very, very thin glass filaments or

0:18:43.980000 --> 0:18:46.220000
 fibers to carry light.

0:18:46.220000 --> 0:18:51.540000
 So light is being used to carry your
 data, not electrical energy, light

0:18:51.540000 --> 0:18:55.780000
 energy. It's much thinner than ethernet
 cable and it's much more flexible

0:18:55.780000 --> 0:19:00.620000
 than ethernet cable and it's typically
 more costly than ethernet cable.

0:19:00.620000 --> 0:19:05.620000
 So there's two general classifications
 of fiber optic cable, multi mode

0:19:05.620000 --> 0:19:09.260000
 fiber and single mode fiber.

0:19:09.260000 --> 0:19:12.120000
 So let's talk a little
 bit about that.

0:19:12.120000 --> 0:19:14.020000
 So that's one thing you'll
 need to understand.

0:19:14.020000 --> 0:19:16.860000
 If somebody says, hey, I need you to
 get me a fiber cable from my ethernet

0:19:16.860000 --> 0:19:21.980000
 port, you'll need to ask them, do I need
 a multi mode or single mode cable?

0:19:21.980000 --> 0:19:25.920000
 So the main differentiator
 is the size of the core.

0:19:25.920000 --> 0:19:26.820000
 What do I mean by the core?

0:19:26.820000 --> 0:19:29.880000
 Let me go back one slide here for just
 a second and point out that in

0:19:29.880000 --> 0:19:34.480000
 a fiber optic cable, this little tiny
 piece of fiber right here is what

0:19:34.480000 --> 0:19:38.440000
 we call the core and that's the strand
 of glass used to actually carry

0:19:38.440000 --> 0:19:44.480000
 the light. And then this here, the cladding
 is also composed of another

0:19:44.480000 --> 0:19:48.860000
 layer of glass that's
 surrounding the core.

0:19:48.860000 --> 0:19:52.140000
 Now the cladding, however, has a different
 refractive index, which basically

0:19:52.140000 --> 0:19:56.920000
 ensures that the light that bounces
 around remains totally within the

0:19:56.920000 --> 0:19:59.660000
 core. We don't want the
 light leaving the core.

0:19:59.660000 --> 0:20:04.020000
 That core might be miles and miles long
 and it has to contain the light

0:20:04.020000 --> 0:20:07.700000
 that enters in it so it pops
 out on the other side.

0:20:07.700000 --> 0:20:10.180000
 So now we know what the core
 and the cladding is.

0:20:10.180000 --> 0:20:13.340000
 What does this have to do with multi
 mode fiber versus single mode fiber?

0:20:13.340000 --> 0:20:17.480000
 Well, if we're looking at the core,
 as we can see here in this slide,

0:20:17.480000 --> 0:20:21.320000
 multi mode fiber has a
 larger diameter core.

0:20:21.320000 --> 0:20:26.220000
 It's thicker. So it allows multiple
 modes or rays of light to propagate.

0:20:26.220000 --> 0:20:30.860000
 Where a single mode fiber has a very
 narrow core, only allowing a single

0:20:30.860000 --> 0:20:34.320000
 mode of light. Was
 this translate to?

0:20:34.320000 --> 0:20:36.700000
 Well, multi mode fiber is cheaper.


0:20:36.700000 --> 0:20:39.980000
 It's less expensive because the type
 of light is going to be generated

0:20:39.980000 --> 0:20:47.060000
 by a less expensive light source, typically
 an LED or an inexpensive laser.

0:20:47.060000 --> 0:20:51.060000
 Whereas single mode fiber is more expensive
 cable because it requires

0:20:51.060000 --> 0:20:56.020000
 a more expensive high powered
 laser to generate that light.

0:20:56.020000 --> 0:20:59.120000
 Another distinctive difference between
 multi mode and single mode fiber

0:20:59.120000 --> 0:21:01.580000
 is how long they can be.

0:21:01.580000 --> 0:21:03.840000
 Multi mode fiber is
 limited on distance.

0:21:03.840000 --> 0:21:06.700000
 You're typically going to be using
 it for connections between devices

0:21:06.700000 --> 0:21:10.460000
 that are anywhere from 20 to 50
 meters apart from each other.

0:21:10.460000 --> 0:21:15.060000
 But if I need to run a fiber optic cable
 across a long distance, that's

0:21:15.060000 --> 0:21:17.160000
 where I'm going to be using
 a single mode fiber.

0:21:17.160000 --> 0:21:22.620000
 Single mode fiber can support distances
 up to several thousands of kilometers.

0:21:22.620000 --> 0:21:27.220000
 Now, if I was actually holding up some
 fiber optic cables in my hands,

0:21:27.220000 --> 0:21:31.800000
 how would I be able to tell which one
 is single mode fiber and which one

0:21:31.800000 --> 0:21:33.740000
 is multi mode fiber?

0:21:33.740000 --> 0:21:36.420000
 Well, hopefully there's going to be
 some printing on the outer jacket

0:21:36.420000 --> 0:21:38.520000
 of the cable that actually
 tells you that.

0:21:38.520000 --> 0:21:39.940000
 That is your best bet.

0:21:39.940000 --> 0:21:43.260000
 Take out your magnifying glass
 and look for that printing.

0:21:43.260000 --> 0:21:46.980000
 Another way that you can tell, now
 this isn't always standardized, is

0:21:46.980000 --> 0:21:49.100000
 the color on the outside
 of the cable.

0:21:49.100000 --> 0:21:53.860000
 You can see here that generally speaking,
 your various flavors of multi

0:21:53.860000 --> 0:21:58.180000
 mode cable will usually
 be orange in color.

0:21:58.180000 --> 0:22:02.700000
 Orange is the most common color
 here of multi mode cables.

0:22:02.700000 --> 0:22:06.200000
 Where as single mode cable
 is usually yellow.

0:22:06.200000 --> 0:22:11.720000
 So single mode fiber is typically
 yellow in color.

0:22:11.720000 --> 0:22:16.620000
 And lastly, fiber cables are terming with
 a variety of different connectors

0:22:16.620000 --> 0:22:18.200000
 as you can see here.

0:22:18.200000 --> 0:22:21.840000
 So if you ever see these types of connectors
 on the end of a cable, you're

0:22:21.840000 --> 0:22:25.300000
 looking at a fiber optic cable.

0:22:25.300000 --> 0:22:27.200000
 So that concludes this
 particular video.