- [Narrator] An access point will advertise
a Basic Service Set, BSS, which is its capabilities.
These advertisements are done via unique BSS identifier
which is formed from the radio's MAC address.
The BSSID uniquely identifies this AP
from others in the area, even those that may be advertising
a network of the same name.
Speaking of network names, wireless networks
broadcast the presence of various networks
via beacon packets with Service Set IDs or SSIDs.
SSIDs can be up to 32-bytes long
and can consist of alphanumeric characters
as well as various symbols and languages.
SSIDs are the human readable network names
that show up on my list of available networks
when I'm trying to find Wi-Fi on my phone.
Once I choose a network, my phone will actually connect
to the BSSID of the AP with the strongest signal,
and also advertising the chosen SSID.
An AP almost always bridges clients to a wired network
via a switch.
Cisco refers to this connection to a switch
as a Distribution System.
If multiple SSIDs are present from a single AP,
it has a unique BSS and BSSID for each unique SSID.
When multiple APs are connected together with switches,
this wireless coverage area is referred to
as an Extended Service Set.
While it's almost never used, there is also a concept
known as an Ad Hoc Wireless Network.
In essence, it's a connection
between only a small handful of devices and no more.
The network is represented
as an Independent Basic Service Set.
APs can operate in a few different modes.
In Repeater mode, an AP will connect
to an adjacent access point
and then rebroadcast the same SSID
to expand the coverage area for clients.
This type of connection isn't ideal,
as it can add congestion to a busy frequency.
A Workgroup Bridge will act as a wireless client,
connecting to a local access point,
then it will bridge this to a wired port
for connecting to a client device.
An Outdoor Bridge will connect networks together
over distances outdoors.
A Mesh network is a conglomeration of multiple APs
daisy chaining together wirelessly to extend a network.
I'm not a proponent of Mesh networks,
as they increase complexity
and lower overall throughput for clients.
These are the most basic fundamentals of wireless operation.
So expect to see some of them on the test.