TCP vs UDP : https://coding-factory.tistory.com/614 , https://velog.io/@ruthetum/TCP-UDP 3/4way hand shaking https://mindnet.tistory.com/entry/%EB%84%A4%ED%8A%B8%EC%9B%8C%ED%81%AC-%EC%89%BD%EA%B2%8C-%EC%9D%B4%ED%95%B4%ED%95%98%EA%B8%B0-22%ED%8E%B8-TCP-3-WayHandshake-4-WayHandshake OSI 7 Layer : https://shlee0882.tistory.com/110 OSI 7 Layer 캡슐화/역캡슐화 : https://iworldt.tistory.com/161 VPC (aws) : h..