Encryption
Custom DES processing with Base64 transport encoding.
Independent build · Security · Networking
Secure Messaging
Protected concurrent conversations by combining end-to-end encryption with multi-threaded socket handling, resulting in secure delivery even when recipients were offline.
Chapter 01
The friction
A messaging system must preserve confidentiality while continuing to deliver messages reliably across concurrent users and intermittent availability.
Chapter 02
The connection
The system combines custom DES encryption and Base64 encoding with a multi-threaded socket architecture and a persistent offline inbox.
Chapter 03
The evidence
01
Protected content with a custom DES implementation and Base64 encoding, resulting in an end-to-end encrypted communication path.
02
Handled multiple active users through a multi-threaded client-server architecture, resulting in concurrent socket communication.
03
Preserved undelivered messages in XML-backed offline inboxes, resulting in reliable delivery across disconnected sessions.
JavaSocket programmingDESMultithreadingXML
Chapter 0401 02 03 04
Inside the system
Concurrent server
Multi-threaded socket handling supports multiple active clients.
Offline inbox
Persistent XML storage retains messages until recipients reconnect.
Delivery flow
Client-server events coordinate sending, receiving, and deferred delivery.
Next case study