- TCP
- ICMP
![image.png](https://img.ynchen.me/2023/02/0984bdedbc323ecd40f88f4cecc36af9.webp)
- The UDP datagram is encapsulated in the IP datagram and sent
- Checksum is optional when using ipv4
- Default: All 0s
- Include part of the IP headers, allowing detect datagram delivered to the wrong destination.
- Self contained datagrams
- Connectionless
- Unreliable delivery