Internet Protocol (IP)
Responsible for addressing and routing of packets
Two versions in current in use
- IPv4: a 192 bit (24 byte) header, uses 32 bit addresses.
- IPv6: Mainly developed to increase IP address space due to the huge growth in Internet usage (128 bit addresses)
Both versions have a variable length data field
- Max size depends on the data link layer protocol.
- e.g., Ethernet’s max message size is 1,492 bytes, so max size of TCP message field:
1492 – 24 – 24 = 1444 bytes