Binary to Decimal Conversion 27 128 26 64 25 32 24 16 23 8 22 4 21 2 20 1 IP Addresses A computer only knows binary (0s and 1s) An IP address in IP version 4 has 32 bits (separated by periods into 4 octets) 11000000.10101000.00001010.10010110 IP Addresses Humans are more familiar with decimal numbers, so we use a Dotted decimal format An IP address of 192.168.10.150 has a Binary equivalent of 11000000.10101000.00001010.10010110 Conversion can be done in Windows calculator. Make sure to include any leading zeros to make a full octet. IP Addresses IP Addresses have 2 Parts: Network Number and Host Number. In the IP Address 192.168.10.150 the Network Number is 192.168.10 and the Host Number is 150 The Correct Notation is 192.168.10.0 and 0.0.0.150 IP Addresses IP Address Classes Class A Decimal 0-126 Binary 00000000 01111110 B 128-191 1000000 10111111 C 192-223 11000000 – 11011111 IP Addresses • In binary, the highest number 8 bits can designate is 11111111 or 255 in decimal. IP Class Subnet masks Class Subnet mask - Decimal Subnet mask - Binary A 255.0.0.0 11111111.00000000.00000000.00000000 B 255.255.0.0 11111111.11111111.00000000.00000000 C 255.255.255.0 11111111.11111111.11111111.00000000 IP Addresses To differentiate between the network portion and the host portion, network administrators use subnet masks. The default subnet mask for the Class C IP address of 192.168.10.150 is 255.255.255.0 In binary: 11000000.10101000.00001010.10010110 11111111.11111111.11111111.00000000 11000000.10101000.00001010.00000000 192 .168 .10 .0 Convert decimal to binary in Windows calculator • Go to Start, Run and type in: calc • Type in a decimal number: 100 • Click on radio button beside bin (binary) and the binary equivalent will show in the answer box: 1100100 (7 bits) • Be careful the answer box doesn’t show leading 0s: 01100100 (8 bits) Ipconfig - Windows 2000 • • • • • Go to Start, Run and type in cmd Type in ipconfig /? Type in ipconfig /all Type in ipconfig /release Type in ipconfig /renew PING Packet Internet Groper (PING) is a utility that can verify that TCP/IP is installed, bound to the NIC, configured correctly, and communicating with the network. • Type ping 127.0.0.1 • Type ping your IP address • Type ping another computer in your network • Type ping your default gateway • Type ping www.yahoo.com (internet host) An Example • Subnet a Class C network, 200.133.175.0, into 14 subnets for security, traffic control and multiple locations. • 2n - 2 = number of subnets (need minimum of 14 subnets) where n = number of bits borrowed 2?-2 > 14 24-2 = 16 • Borrow four bits = subnet mask 255.255.255.240 • Table An Example 200.133.175.0 11001000.100000101.10101111.00000000 255.255.255.240 11111111.11111111.11111111.11110000 Example