Andrey Ludwig

personal site

Hi, I am Andrey Ludwig

Results-driven Computer Programmer with 30 years of experience in developing and implementing software solutions.

Skilled in multiple programming languages and technologies, with a strong expertise in C# and networks. Successfully completed numerous software projects as a solo developer or team leader.

Currently working as a self-employed contractor.

Services

Front-end

  • WPF applications (Windows)
  • CLI utilities (Windows & Linux)
  • ASP.NET sites (multi-platform)
  • Qt (multi-platform)

Back-end

  • Services and daemons, database design, experience with MySQL/MariaDB, MS SQL, Oracle
  • Message driven multi-service systems with Apache Kafka, Rabbit MQ, proprietary protocols
  • Windows and Linux, C# and C/C++
  • From Hi-End servers to Raspberry Pi and Arduino

Integration

  • Years of experience in communicating with all types of hardware. From GNSS trackers to video cams, from PTU to satellite modems
  • Experience with dozens of Serial/Network/Analog protocols
  • Protocol reverse engineering with Wireshark

Got a rack full of diverse hardware and want to rule it all from one neat app over the network?
I can make it happen.

Current activity

I am working with Software-Defined Radio in the rapidly evolving area of digital communications.

Completed projects

Active Wi-Fi monitoring

2021-2022

Technologies: .NET, MS VS & C#, SQLite, HASP;TCP/IP, Wi-Fi;
Customized Linux kernel drivers for Realtek, Ralink Wi-Fi adapters;
Functionality: Simultaneous control of 8+ Wi-Fi adapters in Linux box from Windows WPF App; Efficient quick detection of all APs/Clients in 2.4GHz and 5GHz bands, logging, alerting, white/black listing;
Special modes (e.g. channel jamming, forced disconnect);
Hardware: Windows PC, Linux box, remote Wi-Fi probes built from OpenWrt APs;

Video security system

2019-2021

Technologies: .NET, MS VS & C#, Python;
TCP/IP, serial comm / digital IO; Image recognition;
Video-over-IP, RTSP, Pelco-P/D;
Functionality: Online video, remote PTU & optics control;
Hardware: Windows server and Raspbian OS box;
Multispectral HD Cameras / Lenses;

Corporate VPN solution

2017-2018

Technologies: C++, Qt, Linux kernel driver;
FPGA integration, AES, TCP/IP;
Functionality: TCP server for VPN tunnels, encryption on secure FPGA board;
Upper level services based on custom XMPP extensions;
Hardware: Server — Linux PC+FPGA;
Clients — Windows, Linux, Android, Mac, iOS;

Advanced network security monitoring

2013-2017

Technologies: .NET, MS VS & C#, MS SQL, HASP;
TCP/IP, promiscuous packet capture (PCAP);
Functionality: Online protocol parsers for 20+ protocols (DNS, FTP, SMTP, POP3, Telnet, HTTP, Torrent etc.);
Special modes: MitM, Arp Spoofing, SSL stripping, Evil Twin, Wi-Fi deauth. etc. over Ethernet, ADSL, Wi-Fi;
Hardware: Windows server, Linux box;

Billing system for Internet provider

2010-2013

Technologies: .NET, MS VS & C#, Javascript, IIS & ASP.NET, MS SQL; Paypal API;
TCP/IP, SNMP, RADIUS, Telnet/SSH, IP routing, Wi-Fi, SQL;
Functionality: Internet access control, automatic billing;
Hardware: Cisco 3600, 7200.

Management system for mobile satellite stations & stationary SATCOM teleports

2000-2010

Technologies: Delphi for .NET, MS VS & C#, IIS & ASP.NET, MS SQL;
TCP/IP, SNMP, HTML, serial comms, NMEA, SQL;
Functionality: Single management solution for SATCOM teleport;
Environmental control, rack monitoring, antenna tracking, data channels status, equipment inventory etc.
Hardware: Windows server, satellite dishes from 2.4m to 16m diameter, transceivers / BUCs, satellite modems, GPS clock, weather station, analog/digital sensors, routers/switches etc.

Computer Telephony system for Telecom operator

1999-2000

Technologies: Delphi, C++; ActiveX & COM; Oracle DB;
Analog FXO/FXS, Voice-Over-FrameRelay, Voice-Over-IP;
Functionality: Business mailbox with concierge functionality;
Hardware: Windows server, Motorola, RAD, Nuera, Comstream, Comtech;

Monitoring system for ground satellite station

1995-1999

Technologies: Pascal/Delphi, IIS & ASP.NET, Interbase;
TCP/IP, serial comms, analog telephone lines;
Functionality: data channels monitoring & control, antenna tracking control;
Hardware: Windows server, satellite modems, voice/data multiplexers, antenna tracking, UPS etc.