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Well, this is an interesting challenge and it really is trying to bring all of

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these concepts

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of RF and channels and bands and try to turn it into a wireless networking

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conversation

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because at the end of the day we have to be able to deploy access points and

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set the channels

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and make sure that we don't have interference inside of our environment.

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And so when we look at a building like this, I mean this would probably be a

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four plan

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that has rooms in here and hallways and all kinds of things, but we're just
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that has rooms in here and hallways and all kinds of things, but we're just

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going to keep

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it simple, say that we've got this physical space, we have seven different

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access points

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and we see the cells that are defined by each AP.

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Now if the access points transmit powers turned up, it's going to be a lot

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larger.

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We've got maybe some smaller cells in here.

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Maybe the access point isn't communicating quite as strongly as the others and

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so that

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will happen in real world as well where we'll have different sizes of cells.

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So our job is to take these four channels that we were given and create a non-
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So our job is to take these four channels that we were given and create a non-

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overlapping

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design by using them.

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Now notice we were given six different channels and we have seven different

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cells here.

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So I'd say, well wait a second, how do I do this?

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I'm going to have to reuse one of them.

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Well believe it or not, we can reuse these as many times as we want so long as

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the cells

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aren't overlapping.

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And so this access point here and this access point up here and this access

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point down

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here could all in theory use the same channel because there's a gap that exists

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among all
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three of these.

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They could all use channel 36, the first one in our list if we so desire.

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And so when we're making a plan here, we probably want to say, well let's just

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start with the

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first one again.

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We'll say, hey I'm going to make this channel 36 and then I could make this one

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down here

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channel 40 and then I come in here to the middle and I say, all right this is

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going

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to be channel 108.

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Now I could keep going, I could say this is channel 112 except notice that

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these two are really

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far apart and so I could go back to channel 40 here.
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far apart and so I could go back to channel 40 here.

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And then I could say that, all right well 108 and 40, well these two are far

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apart as well

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and so I could make this channel 36 again.

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And then hey, well might as well keep it up, I could go to channel 108 over

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here and channel

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40 down here.

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So I just made a non overlapping design using three channels and this is

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actually what we

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used to do when we had our 2.4 gigahertz as our only space, we only had three
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used to do when we had our 2.4 gigahertz as our only space, we only had three

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non overlapping

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channels.

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And so we always had to be a little bit more willing to or I guess creative

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maybe at times

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to make sure that our channels and our cells were tuned in such a way that we

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could get

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through this with only three.

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Now is that necessarily optimal if we have more channels available?

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Well maybe not because even though we said that these three are all on 40, yeah

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there's

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a little bit of a gap here and a gap here but are we really sure that that's
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a little bit of a gap here and a gap here but are we really sure that that's

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where the

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wireless communications end?

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What if there is a little bit of overlap here?

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And so if we only had three channels available we might stick with that.

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But if we have more channels available which we do today here in this challenge

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then we

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might as well use them.

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So let's go ahead and do this with more channels.

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Well let's start with 36 again in 40 and 108 but now again because we have six

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channels

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I might as well go to 112 here, 132 here, 136 and then I am out of channels.
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I might as well go to 112 here, 132 here, 136 and then I am out of channels.

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Well here's the good news.

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This access point here is as far away as it gets from the access point in the

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upper left

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so I would just assign this to channel 36 again.

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That is how we might want to go about doing this if we're talking about being

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very safe.

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Now lastly interestingly might notice that we could have bonded these channels

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together

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as well.

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36 and 40 are adjacent to one another.
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36 and 40 are adjacent to one another.

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108 and 112 are adjacent.

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132 and 136 are adjacent to one another as well.

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Now we didn't exactly specify that they're adjacent.

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So if this is what you did with non bonded channels then that's perfectly fine.

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And again there's really a lot of writing answers to how to go about doing this

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.

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But what if we wanted to bond these channels together and use them to create a

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diagram that

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is not overlapping.

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Well I could put 36 and 40 together here and that would be again a 40 megahertz
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Well I could put 36 and 40 together here and that would be again a 40 megahertz

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channel

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now.

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But 108 and 112 down here and I could do 132 and 136 here in the middle.

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And just like with our original three channel design we're going to do the same

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concept because

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we effectively have three channels.

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There are three different 40 megahertz channels.

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So I'll make this one 108, 112 as well since it's as far away as it can be from
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So I'll make this one 108, 112 as well since it's as far away as it can be from

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that one

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or the furthest away from that one.

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I'll make this one a 3640.

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I'll make this a 132, 136 and I'll make this one down here a 108, 112.

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We might still see a little bit of interference from some of the nearby cells

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here and so we'd

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have to be careful with this design.

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But it is certainly an option for us to consider as far as deploying 40 mega

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hertz channels

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this have 20 megahertz channels.

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So again however you ended up doing this challenge perfectly fine if you did
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So again however you ended up doing this challenge perfectly fine if you did

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the first one where

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you only use three if you did the middle one where you just spread them all out

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and hey if

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you did happen to do it with bonded channels then great.

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But the main purpose of this conversation and this challenge is to make sure

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that we understand

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we need to pick a channel.

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We need to assign our access points to use those channel or that channel and we

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need to make

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sure that while our cells should overlap we do want overlap between ourselves

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as we said

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that helps with seamless wireless roaming.

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We do not want to see overlap between cells that have the same channel assigned
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We do not want to see overlap between cells that have the same channel assigned

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.

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I hope there's been informative for you and I'd like to thank you for viewing.