chiTCP

chiTCP is a programming assignment where students have to implement the TCP protocol. It provides a framework for students to bypass the operating system’s TCP stack and, instead, use a sandboxed and testable TCP stack that runs in userspace (instead of kernelspace). All the details of how TCP interacts with the other layers of the protocol stack (including how packets are handed down to the network layer, and how data is passed up to the application layer) are already implemented for the students, who can then focus on implementing the TCP protocol itself. Furthermore, chiTCP also allows students to write socket-based network applications on top of their TCP implementation (by using a “chisocket” library instead of the standard socket library). If two students write standard-compliant versions of TCP, their applications will be able to communicate over a real network.

• Introduction
• The chiTCP Architecture
• Installing, Building, and Running chiTCP
  • Software Requirements
  • Building
  • Running
• Implementation Guide
  • Implementing RFC 9293
  • Implementing the tcp.c file
  • The tcp_data_t struct
  • The tcp_packet_t struct
  • The chitcpd_update_tcp_state function
  • The chitcpd_send_tcp_packet function
  • The chitcpd_timeout function
  • The logging functions
• Assignment 1: TCP over a Reliable Network
  • Implementing the TCP 3-way handshake
  • Sending and receiving data
  • Connection tear-down
• Assignment 2: TCP over an Unreliable Network
  • Implementing a Timer API
  • Retransmissions
  • Persist timer
  • Out-of-order delivery
• Testing your Implementation
  • Automated tests
  • Running and debugging individual tests
  • Running categories of tests
  • Producing a grade report
  • Echo server and client
  • The “simple tester”
  • Producing a pcap file
  • Wireshark dissector