IT:AD:Subnets
Summary
- A MAC address is hardware based
- An IP address is:
- Composed in software
- Composed of 4 Octets
- Composed of two parts: Network + Host
- Subneting from the firs tpart of the Host portion.
- Types of Addressing:
- IPv4
- 4.3 billion IPs
- IP = 32 bytes (4 x 8bits, which are Octets)
- Running out.
- IPv6
- 2^128 (3.4028237e+38)
- Grouped as Networks
- For More efficient routing.
- The “Network Address” is the Address of the network (eg: 172.16.1.0), ending with 0.
- Classes:
- A:
- Big:
- First Octet: 1-126
- Subnet Mask: 255.0.0.0 (8 bits)
- Number of Networks: 126
- Number of Hosts/Network: 16,777,214
- as for 127, see below for loopback.
- B:
- Medium:
- First Octet: 128-191
- First 2 dedicated to Network
- Last 2 dedicated to Host portion
- Subnet Mask: 255.255.0.0 (16 bits)
- Number of Networks: 16,382
- Number of Hosts/Network: 65,524
- C:
- Small:
- First octet: 192-223
- Subnet Mask: 255.255.255.0 (24 bits)
- Number of Networks: 2,097,150
- Number of Hosts/Network: 255
- D:
- Multicasting
- First octet value range from 224 to 239
- 224.0.0.0 to 239.255.255.255
- Number of Networks: N/A
- Number of Hosts/Network: Multicasting
- So you have to remember - 0-127-192-224-239
* 127.0.0.0 - 127.255.255.255
- Loopback range
- Eg: 127.0.0.1
- Used to test that the Network card is working.
- Examples:
- 172.16.0.0/16
- Gives: 65,524 Hosts