- [Instructor] Let's talk briefly
about connectivity problems.
Here we have a little map of computers
and wireless access points.
We have desktop systems, laptops, mobile devices
and two wireless access points that also act as switches.
The whole thing about connectivity
is you need to be within range
and you need to be running the same protocol
and you don't want to have interference.
So you wanna think about that
whenever you're dealing with wireless networks.
Here is the icon for mobile devices
that shows wifi connectivity.
In fact with full bars, this is what we want.
And this is an icon on say a Windows eight laptop
that shows that there is not wireless connectivity.
You have that X on there, this is what we don't want.
So no connectivity such as this,
when you get an icon like this,
it could be caused by several things.
And one of the primary things is
the wireless access point is not accessible.
It's either not broadcast or it's not turned on.
And you also want to check
if the wireless is turned on on the device.
Now this could be done in a variety of ways.
If you have a mobile device like a smartphone or a tablet,
then you can tap the wireless button to turn it on.
And then you wanna make sure
you scan for the correct networks and connect.
On a laptop you'll often have a function button
that can turn wireless on and off,
and then on the laptop and on the desktop,
you can click on the wireless link
to bring up that wireless bar
and actually scan through everything
or go to your network and sharing center
and try to make your connection.
You can also enable and disable wireless from there
and you can also enable and disable the wireless adapter
from the device manager.
So these are all things that you want to check.
And you might have third party software
that controls your wireless connection,
where you can turn the wireless on and off.
So for no connectivity you wanna make sure
the wireless access point is on and broadcasting
and within range
and make sure that your mobile device or computer
is on broadcasting and everything's enabled
and also within range.
It gets a little bit more difficult to troubleshoot
when you get into limited connectivity.
Limited connectivity could mean a couple things.
One, it could mean that you have
only X amount of data transfer per second,
you know say instead of connecting at
300 megabits per second,
you can only connect at 50 megabits per second.
And that could be caused by a couple things.
That could be caused by the wireless access point,
throttling down the connection
and capping you at a certain speed.
It could also be caused by the distance
of the wireless access point from the device.
It could also be a problem with the protocol used.
You may want connect your laptop via 802.11 AC
but this wireless access point is only broadcasting
on 802.11 G and you make that connection
and then you're only limited to 54 megabits per second.
So there's a lot of possibilities
with limited connectivity as well.
So the best thing to do is to check the protocol
make sure that you have the correct protocol
running on the wireless access point
and on the mobile device or the desktop or laptop.
And then you can also check your antennas,
make sure the antennas are screwed on
and you can adjust their angle
to try to promote the best connection
and then check the distance as well.
Now, another thing about limited connectivity,
is you can have a time based limited connectivity.
Let's say there's a policy in the company
and this wireless access point only broadcasts
between 9:00 AM and 5:00 PM.
Well, you're gonna be limited
to those hours from your computer.
So that's something you gotta keep in mind also,
it's a possibility that you can only
connect at certain times.
That's in our possible limited connectivity.
The next one is intermittent connectivity.
Now, when it comes to PCs,
usually intermittent problems
are the hardest to troubleshoot
but with wireless networks
intermittent problems are a little bit easier.
If you have intermittent connectivity
it could mean one of a couple things.
One, your computer's distance
from the wireless access point is too great.
And two, there's possible interference from other devices
or other electronic devices or microwaves
or HVAC equipment.
So it's really broken down into distance and interference.
So if this computer is say way out over here
it's gonna be a little bit too far
to get that connection to a wireless access point.
You know, if you have say 802.11 N
and you have a computer that's 200, 250 feet out,
out in a warehouse, you know
it's gonna be difficult to get that connection.
So you might get no connectivity
or you might get intermittent connectivity,
where you have a connection, but then it drops out.
And you know, you get that complaint from people a lot.
My connection keeps dropping out.
And in that case, it's the distance
but you might have a bunch of walls in between you
and your computer and the wireless access point.
And again, you might have that interference
with other devices
and electronic equipment and electrical devices.
And that's when the interference comes into play.
Now with both of these, with distance and interference.
If you see intermittent connectivity
when you do have a connection, it'll usually be pretty slow.
So let's say you have an 802.11 AC connection,
if that's the case and you normally are getting
somewhere in the range of 500 megabit per second connections
when you have this intermittent connectivity
and you can connect, you might see connections around
50 or a hundred megabits per second, or even lower.
So if you see that much lower data transfer rate
then you're accustomed to
or what the protocol should provide
when you do have connectivity,
then that intermittent connectivity
is most likely caused by distance or by interference.
Then there's local connectivity.
And what we mean by this
is connectivity to the local area network
but nothing beyond that.
And the local connectivity to the network means
you can connect from your desktop
to other computers on the land
and the wireless access point or points
but you can't get out to internet sites to websites.
You can't download your mail from the internet,
that kind of thing.
If this happens, it's generally an issue
on one of two sides.
One, the computers IP configuration could be wrong,
it's gateway address could be incorrect.
So you do your IP config slash all and check that
or two, it could be a wireless access point issue,
where the wireless access point
is not connecting out to the gateway properly.
Now, if that's the case,
all computers would not be able to get on.
If it's only one system that can't get onto the internet,
then you wanna focus on that one system's IP configuration
and that gateway address.
Sometimes fixing the gateway address,
you know, changing the gateway address will fix the problem.
Sometimes you need to do an IP config, release and renew
and sometimes you need to forget
the networking connection altogether,
forget that wireless connection and then reconnect to it.
And these types of things
can help to fix a lot of these problems, you know,
forget the wireless network and reconnect,
power cycle the equipment, check if the wireless adapter
is enabled in Windows in the device manager
or in the network and sharing center,
or in the third party software,
or press the button the function key on the laptop,
check the wireless software within the mobile device.
And another thing with all of these as well is the antennas.
Of course, you gotta make sure that the antennas are
connected, their screwed on and they're adjusted properly.
Normally I'll adjust these at a 90 degree angle
have one pointing out straight
and then one at a 45 to that,
and one at a 45 degree angle to that guy.
And the same thing on the clients.
Now you can't do much about that with the mobile devices,
but with the PC, you definitely can
cuz that has the external antennas.
So you can adjust those for best connectivity.
So there's some things to look at with connectivity problems
and that's about it for the sub lesson.