DNS System

Implemented a DNS-like distributed naming service with recursive/iterative resolution, caching, and zone transfer over TCP between primary and secondary servers.

Built a multi-component DNS system in Python: client queries over UDP; resolver performs iterative/recursive resolution via root/top-level/authoritative servers; primary and secondary servers support replication via a custom TCP zone-transfer protocol. Implemented structured config/data parsing, logging, and a cache layer; organized components using an MVC-style module split.

Highlights

• Designed and implemented DNS query/response PDUs and debug/log formats.
• Implemented resolver behavior (iterative + recursive) and authoritative server roles (SP/SS).
• Implemented TCP zone transfer protocol and replication flow (SS bootstraps from SP).
• Built config/database parsing and a cache module to speed repeated queries.

What I did

• Implemented core UDP request/response loop for DNS queries and response construction.
• Implemented TCP zone transfer handshake + streaming of database entries.
• Built file parsers for server configuration, root servers list, and zone database format.
• Implemented logging and error/timeout handling to support reproducible testing.

Stack

• Python 3.10
• Sockets (UDP/TCP)
• Linux
• Logging
• Config Parsing