El-Shorouk Academy
Higher Institute for Computer & Term : First
Information Technology Year : third
Dr. Hesham Department of CS
Section Two
Computer Network
❖What is an IP address?
- An IP address is a unique address that identifies a device on the
internet or a local network.
- IP stands for "Internet Protocol," which is the set of rules
governing the format of data sent via the internet or local
network.
- IP addresses are the identifier that allows information to be sent
between devices on a network: they contain location information
and make devices accessible for communication.
IP Address MAC Address
IP Address stands for Internet Protocol MAC Address stands for Media
Address. Access Control Address
IP Address is either a four-byte (IPv4) MAC Address is a six-byte
or a sixteen-byte (IPv6) address. hexadecimal address.
Internet Service Provider provides IP NIC Card’s Manufacturer provides
Address→ Network layer the MAC Address→ Data Link layer
IP Address is the logical address of the MAC Address is used to ensure the
computer. physical address of a computer
IPv4 uses 32-bit addresses in dotted It is a 48-bit address that
notations, whereas IPv6 uses 128-bit contains 6 groups of hexadecimal
addresses in hexadecimal notations. digits, separated by either hyphen
EX IPv4→ 192.168.1.1 (-) or colons(.).
IPv6→ 2001:db8:3333:4444 Example:
:5555:6666:7777:8888. 00: FF: FF: AB:BB: AA OR
00-FF-FF-AB-BB-AA
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❖Difference between IPv4 VS IPv6
IPv4 IPv6
Address Length IPv4 is a 32-bit IPv6 is a 128-bit
address. address.
Fields IPv4 is a numeric IPv6 is an
address that consists alphanumeric
of 4 fields which are address that consists
separated by dot (.). of 8 fields, which are
separated by colon
(:).
Classes IPv4 has 5 different IPv6 does not contain
classes of IP address classes of IP
that includes class A, addresses.
class B, class C, class
D, and class E.
VLSM It supports VLSM It does not support
(Virtual Length VLSM.
Subnet Mask). Here,
VLSM means that
IPv4 converts IP
addresses into a
subnet of different
sizes.
Address In IPv4, the IP In IPv6 the
Representation address is representation of the
represented in IP address in
decimal. hexadecimal.
Checksum Field The checksum field is The checksum field is
available in IPv4. not available in IPv6.
Number of octets It consists of 4 octets. It consists of 8 fields,
and each field
contains 2 octets.
Therefore, the total
number of octets in
IPv6 is 16.
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❖IPv4 (Internet Protocol Version 4):
- The IP address identifies networks, and network hosts like your
home address but for computers.
- IPv4 defines an IP address as a 32-bit number.
X X X X
8 bits 8 bits 8 bits 8 bits
8*4 = 32 bit = 4 bytes [8 bit = byte]
- Each 32-bit IP number consists of two components:
The Network address: The unique international address of the
network like the area code in a phone number.
The Host address: The unique address of a specific host in the
network like the unique number assigned to each house in a
neighborhood.
❖IP Address Classes:
Class A:
Network Host Host Host Network = 8 bits
8 bits 8 bits 8 bits 8 bits Host = 24 bits
Class B:
Network Network Host Host Network = 16 bits
8 bits 8 bits 8 bits 8 bits Host = 16 bits
Class C:
Network Network Network Host Network = 24 bits
8 bits 8 bits 8 bits 8 bits Host = 8 bits
Class D: Multicast
Class E: Experimental
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Class Range Default Number
(1stoctet) Subnet of
mask hosts
A 1 → 126 255.0.0.0 11111111.00000000.00000000.00000000/8 16,777,214
B 128 → 191 255.255.0.0 11111111.11111111.00000000.00000000/16 65,534
C 192 → 223 255.255.255.0 11111111.11111111.11111111.00000000/24 254
D 224 → 239 - - -
E 240 → 254 - - -
− Number of hosts in class A = 2h – 2 = 224- 2 = 16777214
− Number of hosts in class B = 2h – 2 = 216- 2 = 65534
− Number of hosts in class C = 2h – 2 = 28- 2 = 254
❖ Note:
o 127.0.0.0 → 127.255.255.255 can’t be used and is reserved
for loopback testing.
o Numbers of Subnets = 256/magic number or 2n (n is the
number of 1’s in subnet mask)
o Numbers of Hosts = magic number - 2 or 2h – 2 (h is the
number of 0’s in subnet mask)
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❖Addresses Type:
Private Address Ranges
Class A 10.0.0.0 → 10.255.255.255
Class B 172.16.0.0 → 172.31.255.255
Class C 192.168.0.0 → 192.168.255.255
Special Addresses
Diagnostic 127.0.0.0 → 127.255.255.255
Any Network 0.0.0.0
Network Broadcast 255.255.255.255
❖ Conversion from Binary to Decimal.
Ex: Convert (00110010) to binary
Solution:
2^7 2^6 2^5 2^4 2^3 2^2 2^1 2^0
128 64 32 16 8 4 2 1
0 0 1 1 0 0 1 0
➔ (0*128) + (0*46)(1*32)+(1*16)+(0*8)+(0*4)+(1*2)+(1*)= (50)
So→ (00110010) = (50)
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❖ Conversion from Decimal to Binary.
EX: Convert (100)10 to binary
Solution:
2^7 2^6 2^5 2^4 2^3 2^2 2^1 2^0
128 64 32 16 8 4 2 1
0 1 1 0 0 1 0 0
So→ (100) = (01100100)
VLSM Calculation
IP Address: 192. 168. 1. 7
Subnet mask: 255. 255. 255. 128
Solution
Ip address:
11000000 10101000 00000001 00000111
Subnet mask:
11111111 11111111 11111111 10000000
Network part host part
11000000 10100000 00000001 00000000
Network ID → 192.168.1.0
Number of hosts = 2^7=128
Valid host = 128-2= 126
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IP Address: 172. 16. 1. 7
Subnet mask: 255. 255.0.0
Solution
Ip Address:
10101100 00010000 00000001 00000111
Subnet mask:
11111111 11111111 00000000 00000000
Network part host part
10101100 00000001 00000000 00000000
Network ID → 172.16.0.0
Number of hosts = 2^16 = 65536
Valid host = 65536-2= 65534
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❖Try to answer this question.
IP Address: 192. 168. 1. 7
Subnet mask: 255. 255. 255. 0
Solution
Ip address:
11000000 10101000 00000001 00000111
Subnet mask:
11111111 11111111 11111111 00000000
Network part host part
11000000 10101000 00000001 00000000
Network ID → 192.168.1.0
Number of hosts = 2^7=128
Valid host = 128-2= 126
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❖Assignment
Find the network ID and number of host & valid
hosts.
IP Address: 168.71.148.187
Subnet mask: 255. 255. 255. 0
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