Wireless Networking
Dec 14, 2015
Wireless Networking
Wireless Standards
802.11a
802.11b
802.11g
802.11n
Traditional IP addresses are 32-bits long and written in dotted decimal format. These are considered IPv4 format addresses.
172.17.100.203
Since there are only approximately 4.2 billion public IPv4 addresses available (232), the number of available IP addresses will soon be depleted. That is why the world will be switching
over to the IPv6 system soon.
3ffe:1900:4545:0003:0200:f8ff:fe21:67cf
The IPv6 addresses are 128 bits long, written in hexadecimal, and separated by colons (similar to MAC addresses, just longer)
There will be 340,282,366,920,938,463,463,374,607,431,768,211,456
IPv6 addresses available (2128) or approximately 340 Undecillion.
Private IP Addresses
A private IP address is an address that is allowed to travel across an internal network, but not permitted to travel across the Internet. This allows individuals and companies to have a
lot of computers internally, but only require one or more public IP address, preserving the number of available IP addresses.
10.0.0.0 - 10.255.255.255172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255
169.254.0.0 through 169.254.255.255 (Automatic
Private IP Addressing only)
Identify Your Public and Private IP Address
If you are using a Windows-based system, use the IPCONFIG command to
display your current TCP/IP configuration details. To run the
IPCONFIG command, start a Command Prompt session (click on Start, then choose [Run], then [Programs], then [Accessories] and finally [Command
Prompt]). You should get a new command window. In this window, type
IPCONFIG and press <Enter>.
If you are using a Mac-based system, the command is IFCONFIG. Click on
[Go], then [Utilities] and then [Terminal]. In the Terminal window,
type the command IFCONFIG.
Follow The OSI Model
In the TCP/IP data flow, the information flows
down and back up following the Open
Systems Interconnection (OSI) Model.
For this class, we are primarily concerned with
Layers 1-4:
Ethernet/Network cables and wireless signals operate at Layer 1.
Switches communicate at Layer 2.
Routers/Firewalls communicate at Layers 3
and 4.
Why Binary and Hexadecimal?
Internet
Follow the path . . . .
Computer
SwitchRouter
Why Binary and Hexadecimal?On the LAN, the wireless or wired Network Interface
Card (NIC) on the computer is identified by the switch by Media Access Control (MAC) Address which is
displayed in hexadecimal format.
Computer Switch
00:10:aa:a1:2b:cce0:f8:47:aa:ba:81
Why Binary and Hexadecimal?
On the LAN, the NIC on the switch is identified by the internal NIC on the router by the MAC Address
01:a0:cc:a4:4e:1100:10:aa:a1:2b:cc
RouterSwitch
Why Binary and Hexadecimal?
Some routers, like the ones that are in the typical home, have a switch and router combined into one device.
Why Binary and Hexadecimal?
On the WAN, the external facing NIC on the router is identified by other computers on the Internet by Internet
Protocol (IP) Address, which is displayed in dotted decimal format, but actually travels across the Internet in
binary format.
128.122.108.7110000000.01111010.01101100.01000111
216.54.111.220
Internet
Router
Why Binary and Hexadecimal?Follow the path . . . .
e0:f8:47:aa:ba:81
10:f3:22:a1:b2:c1
192.168.1.1
128.122.108.71
32.156.253.20192.168.1.200
Test You Network Connectivity
You can test your connection using the PING command. PING is a command line utility that allows you to send an Internet Control Message Protocol (ICMP) request to another machine on the network which hopefully then replies. If the output indicates there is no response then there could be a problem with the
network configuration or that the site is not available to receive PING requests.
To run the PING program from either the Windows or Mac, simply type the ping command and an IP address or Fully Qualified Domain Name (FQDN). that
The format of the PING command is:
ping remote machines IP address followed by <Enter>.
Therefore to PING www.nba.com, whose address is 216.254.95.72, enter
ping 163.1.2.1 and press <Enter> or ping www.nba.com and press <Enter>
If everything is working correctly you should get the response similar to that shown below:
PING a1570.gd.akamai.net (216.254.95.72): 56 data bytes 64 bytes from 216.254.95.72: icmp_seq=0 ttl=49 time=11.725 ms 64 bytes from 216.254.95.72: icmp_seq=1 ttl=49 time=18.069 ms 64 bytes from 216.254.95.72: icmp_seq=2 ttl=49 time=13.014 ms 64 bytes from 216.254.95.72: icmp_seq=3 ttl=49 time=14.956 ms