-: Cable distribution. 2 2
Now that we've covered all of our copper and fiber cabling 3 3
and their connectors, 4 4
it's time for us to discuss how we're going to run them 5 5
inside of our buildings. 6 6
And this is where cable distribution systems 7 7
are going to come into play. 8 8
Now, a cable distribution system is an organized system 9 9
to connect the network's backbone 10 10
in the main distribution frame 11 11
to the intermediate distribution frames, 12 12
and finally, out to the end user's wall jacks. 13 13
When we design a cable distribution system, 14 14
it should be hierarchal in nature 15 15
so that each cable run is logically placed safely, securely, 16 16
and functionally inside our buildings. 17 17
When we have them fully installed, 18 18
there are going to be a lot of different components 19 19
that make up our cable distribution system. 20 20
First, we have the entrance facilities 21 21
where your WAN connection 22 22
is going to enter into your building. 23 23
This is known as your demarcation point. 24 24
Now, a demarcation point 25 25
is the location at which 26 26
your internet service provider's connection ends 27 27
and your network is going to begin. 28 28
For example, at your home if you have a cable modem, 29 29
the wall jack that you connect to 30 30
is actually not your demarcation point. 31 31
Most of the time, 32 32
there's going to be a box on the side of your house. 33 33
That's where the cable line comes into your property 34 34
from the cable company. 35 35
This is your demarcation point. 36 36
From here the cable is going to be split 37 37
and it's going to be run to all the different wall jacks 38 38
throughout your house. 39 39
Then you can connect your cable modem and your TVs 40 40
to each of those different wall jacks 41 41
to get your connection. 42 42
In a commercial setting, 43 43
there's usually going to be a telecommunications closet 44 44
that contains a box inside of it, 45 45
and this is going to be your demarcation point. 46 46
Basically, your internet service provider, 47 47
whether they're a cable company or a phone company, 48 48
is going to run a cable into this box. 49 49
And they're going to be responsible for all the wiring 50 50
to make the connection work up to this point. 51 51
Now, once it gets to that box, 52 52
anything that goes wrong with it 53 53
after it reaches that box, becomes your responsibility, 54 54
because it's past the demarcation point 55 55
as you go and connect it into your network. 56 56
Now, from this demarcation point or entrance facility, 57 57
you're going to run a cable over to your border gateway 58 58
or your router, 59 59
and then you're going to connect it to your backbone switch. 60 60
Now, this switch is called the backbone 61 61
because everything else in your network 62 62
is going to connect to it. 63 63
If you have a small network, 64 64
you might only have one 24-port switch 65 65
and all of your servers and users are going to connect to it. 66 66
In this case that 24-port switch 67 67
would be your backbone switch. 68 68
But if you work for a large organization 69 69
with hundreds or thousands of users, 70 70
you're going to need more than one switch. 71 71
So you're going to have this backbone switch, 72 72
and then you're going to connect smaller switches to it 73 73
that are called edge switches. 74 74
Now, for example, let's say you have an office building 75 75
with five different floors on it. 76 76
Each floor might have 20 people on it. 77 77
So we could put a 24-port switch 78 78
on each one of those floors. 79 79
Those 24-port switches are all called edge switches. 80 80
They are all going to connect to your users. 81 81
Now, those edge switches 82 82
are going to connect back to the backbone switch 83 83
using what's known as a trunk line. 84 84
Now, we'll talk more about the technology side, 85 85
about how all this works later on. 86 86
Right now we're just focused on the cabling. 87 87
For now, I just want you to realize 88 88
that an edge switch is closer to our end-users, 89 89
and it's going to connect upstream 90 90
back to our backbone switch. 91 91
Now, your backbone switch 92 92
is going to be located in your MDF, 93 93
or your main distribution frame. 94 94
Basically this'll be a telecommunications closet 95 95
and it will serve as your main starting point 96 96
for all of your interior cabling. 97 97
Every other telecommunications closet 98 98
you have in your building 99 99
will reach back to this main distribution frame, or MDF. 100 100
I like to think of it as a trunk of a tree. 101 101
All those branches that come off of it 102 102
will go to our IDFs, 103 103
or the intermediate distribution frames. 104 104
Those are the smaller distribution frames. 105 105
But this trunk is the main distribution frame. 106 106
Now, to connect the MDF to the IDF, 107 107
we're going to use a cable tray 108 108
and we'll run all of our cables within these trays. 109 109
A cable tray is simply a unit or assembly of units 110 110
that form a rigid structural system 111 111
to securely support the cables and raceways 112 112
as our cables go across our building. 113 113
Just like people that need to move around the building 114 114
by walking the halls or taking the elevator up and down, 115 115
our cables have to move horizontally and vertically as well. 116 116
When we move horizontally with our cable, 117 117
we do this inside of the cable trays. 118 118
Now, these are usually located inside of a drop ceiling 119 119
or under a raised floor, 120 120
depending on the construction of your building. 121 121
But as you move vertically up and down between the floors, 122 122
you're going to pass your cables 123 123
through a vertical cross-connect. 124 124
In general, it is the best practice 125 125
to minimize the number of cables 126 126
that have to cross vertically across floors. 127 127
For this reason, 128 128
we usually only run trunk cables 129 129
to connect the main distribution frame 130 130
and its backbone router and switch 131 131
up to the intermediate distribution frames 132 132
and their edge routers and switches 133 133
by using these vertical cross-connects. 134 134
Once you reach an IDF, 135 135
or an intermediate distribution frame, 136 136
you're going to find it's going to contain your edge router 137 137
or edge switches, a patch panel, 138 138
and other associated networking equipment. 139 139
Each IDF is going to be designed to support the floor 140 140
and the offices closest to it. 141 141
If you're in a smaller office building, 142 142
you may only have one IDF per floor, 143 143
but if you're in a really large office building, 144 144
you may have to have multiple IDFs per floor. 145 145
If this is the case, 146 146
you'll usually want to go from an MDF 147 147
to one of the other IDFs on a given floor. 148 148
And then from that IDF, 149 149
which will serve as basically a mini backbone 150 150
for all the other IDFs on that particular floor. 151 151
For each IDF, 152 152
you're going to run the cabling through the cable trays 153 153
to the individual offices and down the walls 154 154
where they connect to a wall jack. 155 155
These wall jacks are normally going to have RJ45 jacks 156 156
in most organizations, 157 157
but you can also use fiber wall jacks 158 158
if you require them for additional security, 159 159
additional distance, or additional speed. 160 160
All right, let's take a quick look at what it looks like 161 161
when we go from the switch in an IDF 162 162
to the desktop of one of our end-users. 163 163
When you go to your office 164 164
and you plug in your new computer into a wall jack, 165 165
there is a lot that's going on behind the scenes 166 166
that as an end-user, you're just not seeing. 167 167
So your computer is going to be connected to the wall jack 168 168
using a patch cable. 169 169
This can be a copper patch cable 170 170
known as a straight-through cable 171 171
if you're using CAT 5, CAT 6, or CAT 7 cable. 172 172
Or, you can use a fiber patch cable 173 173
if you're using a fiber-based cable distribution plan. 174 174
Now, if you're using a copper plant, 175 175
which is what we're going to talk about the rest of this part, 176 176
this wall jack or wall outlet is going to have a connector, 177 177
like an RJ45 connector on the front 178 178
that you plug into with your copper cable. 179 179
Now, the back of this jack is going to have a punch down block 180 180
that terminates a copper cable 181 181
that's going to run through the walls, 182 182
either up into the ceiling or down into a raised floor, 183 183
and then across the cable trays, 184 184
until it reaches back into your IDF, 185 185
your intermediate distribution frame. 186 186
From here, the cable is going to be terminated 187 187
into a larger punch down block. 188 188
This punch down block 189 189
may be attached to the wall separately, 190 190
or it may be on the backside of a patch panel. 191 191
Then we're going to connect another patch cable 192 192
to connect the patch panel 193 193
to the open port on the edge switch 194 194
that's located within this intermediate distribution frame. 195 195
All right, I know I just introduced 196 196
a bunch of new things and terms 197 197
in that quick cabling walkthrough 198 198
that you may not be too familiar with. 199 199
So let's take a moment to dig into those 200 200
and then we're going to return to the distribution 201 201
from the IDF to the end-user again. 202 202
First, I mentioned a punch down block. 203 203
Now, punch down blocks are going to be located in your MDF, 204 204
your main distribution frame, 205 205
and your IDF, your intermediate distribution frames. 206 206
Now, there are four types of punch down blocks 207 207
that you may come across in the field 208 208
as a network technician. 209 209
A 66 block, a 110 block, a Krone block, and a BIX block. 210 210
First, we have a 66 block. 211 211
Now, a 66 block, also known as an M block, 212 212
is used in older analog telephone systems. 213 213
These older 66 blocks were designed for telephone systems 214 214
initially back in 1962, 215 215
and they were designed to support a 25-pair cable 216 216
that came in from your phone company 217 217
and they would run it to your MDF or IDF. 218 218
Then you would punch down those 25-pairs 219 219
into the block to connect those outside phone lines 220 220
to your internal cabling for your phone lines 221 221
within your building. 222 222
For this reason, 223 223
you're usually only going to see 66 blocks 224 224
in your MDF or IDFs 225 225
when they're being used to terminate 226 226
traditional analog phone lines. 227 227
If you're going to be working with a 66 block, 228 228
make sure you have the right blade 229 229
on your punch down tool to support it, 230 230
because it is a different shape 231 231
than the ones that we use 232 232
in our modern network punch down blocks, 233 233
which are known as 110 blocks. 234 234
Now, this is the second type of block we have. 235 235
It's known as a 110 block, 236 236
and it's used almost exclusively 237 237
in American-style networks and patch panels, 238 238
both for voice and data applications. 239 239
110 blocks support high-speed data networks 240 240
for CAT 5 and above copper cabling. 241 241
The 110 block is an improved version of the 66 block, 242 242
and includes the use of insulation displacement 243 243
contact connectors to terminate those twisted pair cables 244 244
onto those punch down blocks. 245 245
The 110 blocks use a similar punch down tool 246 246
to the 66 block, 247 247
except it's going to have a different blade 248 248
that's designed for the 110 block. 249 249
Now, when you install cables on a 66 or a 110 block, 250 250
you're going to use a tool known as a punch down tool. 251 251
This tool comes with a small blade 252 252
that's going to be used to push the twisted pair cable 253 253
down onto the teeth of the block, 254 254
and then cut off the excess cabling. 255 255
This punch down will allow the connectors on the block 256 256
to bite into the cable and make the network connection 257 257
and hold the individual copper wires in place. 258 258
I'm going to show you how this works 259 259
in a demonstration later on in the course. 260 260
The third type of block you have 261 261
is going to be called a Krone block. 262 262
Now, a Krone block 263 263
is a proprietary European alternative to a 110 block. 264 264
The Krone block was developed 265 265
by a German telecommunications company back in the 1970s, 266 266
and it looks a lot like a 110 block. 267 267
The only real difference 268 268
is that the contacts of the punch down block 269 269
are at a 45 degree angle when you're using a Krone block. 270 270
This is as opposed to the 90 degree straight-on angle 271 271
used by a 110 block. 272 272
If you're going to work on a Krone block, 273 273
you need to have a specific Krone-style punch down tool 274 274
due to the angling of these contacts. 275 275
The fourth type of block you might encounter 276 276
is known as a BIX, or B-I-X block. 277 277
Now, the BIX block is another proprietary punch down block. 278 278
The BIX block was created in the 1970s by Nortel Networks, 279 279
and they come in various sizes. 280 280
Again, if you work on a BIX block, 281 281
you're going to need a BIX-specific punch down tool. 282 282
Now, all that said, 283 283
the most common punch down block 284 284
that you're going to run across in the field is a 110 block. 285 285
Personally, I've been working on networks 286 286
for over two decades, 287 287
and I've only worked on 110 blocks 288 288
for the last 15 years or so. 289 289
And before that it was a mixture of 66 and 110 blocks. 290 290
I am only mentioning the Krone and BIX blocks here 291 291
in case you happen to be working overseas, 292 292
or you see it on some legacy network, 293 293
and you run across them. 294 294
The next thing we need to discuss is patch panels. 295 295
Now, a patch panel is used to keep your data center 296 296
or server room more organized, 297 297
as well as making it easier to move, add, or change 298 298
your cable distribution infrastructure into the future. 299 299
In general, a patch panel will have two sides. 300 300
One side you'll find all the network jacks, 301 301
such as a series of RJ45 connectors 302 302
if you're using copper cabling on your network. 303 303
And then on the other side, 304 304
you're going to find what looks like a 110 block punch down, 305 305
where you're going to punch down those copper cables to. 306 306
So why would I want to use a patch panel? 307 307
After all, can't I just put an RJ45 connector 308 308
onto the end of one of the copper cables 309 309
coming into the IDF, and plug that directly into my switch? 310 310
Well, you could, but it's not considered a best practice. 311 311
Instead, you should always connect the wall jack's cable 312 312
to a 110 block or to the back of a patch panel. 313 313
This allows the patch panel 314 314
to provide you with an easy-to-use network jack 315 315
on the front side of it, 316 316
and this can then be connected to the switch 317 317
using a patch cable. 318 318
You see, patch panels are really cheap and inexpensive. 319 319
And so they protect me from causing damage 320 320
to the more expensive network components 321 321
when I'm moving people and cables around inside my networks. 322 322
You see, if I was directly plugging and unplugging jacks 323 323
into the switch port 324 324
every single time I wanted to make a change, 325 325
eventually I'm going to damage that switch port. 326 326
That switch is going to cost two, three, or $4,000 to replace. 327 327
Whereas if I broke the patch panel, 328 328
it's only going to cost me 10 to $20 to replace. 329 329
The more you plug and unplug a cable into a port, 330 330
the more wear and tear occurs. 331 331
And eventually that port will fail. 332 332
For this reason, I would rather the patch panel fail 333 333
than a port on my expensive switch. 334 334
So I'm going to punch down the cable 335 335
to the back of the patch panel 336 336
and connect a patch cable 337 337
from the front jack of the patch panel 338 338
into the port number of port number one on the switch, 339 339
going from port number one of the patch panel. 340 340
If I need to move that port to something else, 341 341
I'll unplug it from port number one on the patch panel 342 342
and plug it into the other port 343 343
on the patch panel that I want. 344 344
This way, I can make the switch connections directly 345 345
from the patch panel instead of on the switch. 346 346
This is great for network management, 347 347
and it saves you a lot of troubleshooting, 348 348
and prevents causing damage to the switch ports 349 349
on your switches. 350 350
In addition to copper patch panels 351 351
which rely on these punch down blocks, 352 352
you may also run across fiber patch panels, 353 353
which are known as fiber distribution panels. 354 354
Now, unlike copper patch panels, 355 355
there is no punch down on the backside 356 356
of these fiber panels. 357 357
Instead, these fiber distribution panels 358 358
use fiber connectors like LC, ST, SC, and MTRJ. 359 359
Now, both on the front 360 360
and back of these fiber distribution panels, 361 361
you're going to have a jack. 362 362
And essentially it's just going to be a coupler 363 363
from the fiber cable 364 364
connected to the backside of the patch panel, 365 365
to the fiber patch cable 366 366
that's going to attach on the front side. 367 367
Then you go from the front side 368 368
of the fiber distribution panel using a patch cable, 369 369
up to the switch port on the switch. 370 370
Another thing the fiber distribution panels can do for you, 371 371
is actually connect fibers from different types. 372 372
For example, 373 373
you might have an SC on the back and an ST on the front, 374 374
or MTRJ on the front. 375 375
All right, now that we covered all the different pieces, 376 376
let's put it all back together. 377 377
First, I have a workstation sitting in someone's office. 378 378
I'm going to take a patch cable 379 379
and connect it to the wall jack. 380 380
Then I'm going to take that copper cable 381 381
that's being punched down on the backside of that wall jack 382 382
and connect it to the IDF through the cable trays. 383 383
And then I'm going to punch it down 384 384
to the 110 punch down block. 385 385
Next, we're going to connect a copper cable 386 386
from the 110 punch down block 387 387
to the punch downs on the back of a patch panel. 388 388
Finally, we're going to connect a patch cable 389 389
to the front of the patch panel, 390 390
and connect that directly to the switch port 391 391
on my switch. 392 392
If I wanted to use fiber instead of copper here, I could. 393 393
We would just replace the switch with a fiber switch, 394 394
the patch panel with a fiber distribution panel, 395 395
and the wall jack with a fiber wall jack. 396 396
In either case we're allowing this one long run 397 397
from the end-user's desktop, all the way to the switch 398 398
to be broken down into multiple pieces. 399 399
This gives us additional flexibility 400 400
if we need to move it or repair it later on. 401 401
By connecting everything in this manner, 402 402
our cable distribution system 403 403
is going to be working together 404 404
in a typical copper cable installation, 405 405
and give us lots of places where we can troubleshoot 406 406
or fix things if something breaks. 407 407
I don't have to run a single cable 408 408
from the switch all the way through the wall 409 409
and back to the end-user every time I have a problem. 410 410
Instead, let's pretend that I have a cable 411 411
that breaks between the switch and the patch panel. 412 412
Well, I can just unplug it and replace that patch cable. 413 413
If one between the punch down block 414 414
and the patch panel gets broken, 415 415
I could just replace that and re punch it down. 416 416
It would just take me a couple of seconds. 417 417
By having a lot of different places to troubleshoot 418 418
or fix this cable at, 419 419
it's going to give me more options 420 420
to get the network up and running that much quicker 421 421
if I have to do something 422 422
to troubleshoot an issue for a customer. 423 423
This way I don't have to run an entirely new cable 424 424
every time somebody wants to move a machine 425 425
or every time a machine has a cable that gets broken 426 426
somewhere between the switch and that end-user.