Senior Software Entwikler

1/2016 – 12/2016

Technologies like DPDK, fd.io, openFastPath, OpenDataPlane and 6windgate open a new era in packet processing. A full featured firewall with 100 Gbps minimal throughput is not far away. Using these technologies, I work on:
- Optimisation and analysis of each line of code in order to get packet processing and rule engine very fast. Scalability, NUMA systems and number of CPU cycles are on test with each git commit.
- Design and implementation of an advanced engine for real time network event tracking system, within 10 million packets per second context, is challenging but also a nice brain exercise.
- Implementation from scratch of a resource management software which scans the system on which it is running and provides a smart resource distribution towards all subsystems.
- Automatic assembling of an universal, bulletproof Linux image is important as always. But also to get it running on generic, unknown hardware, as well as installation from a hybrid iso image had to be implemented.
I was in contact with technologies from companies like Proofpoint (former Emerging threads), 6wind, Kaspersky Lab, NetStar, geoIP.

Netzwerk-Sicherheit, SSL / TLS, Red Hat Enterprise Linux (RHEL), Linux (Kernel), Python, C++, Linux Entwicklung, TCP/IP, Telekommunikation / Netzwerke (allg.)

5/2014 – 11/2015

Working on Next Generation Firewall proved to be very interesting but also challenging. I am working on :
* high performance packet processing engine using advanced Deep Packet Inspection library (C/Linux/Kernel/MongoDB)
* various Linux services like: VPN, AAA, High Availability, etc. (Python/Linux)
* assembling a bulletproof Linux image by implementing and maintaining an advanced build-system (Python/System Scripting/Linux)
* performance measurements and optimization, new hardware evaluation (Ixia state of the art equipment/ Linux/ Networking)
* advanced web interface (AngularJS/RubyOnRails/SQL/MongoDb)
* maintaining a sophisticated test automation system with a complex infrastructure (Visualization/TDD/BDD)

All this in a Mission Critical Environment with Agile and true Teamwork.

Embedded Linux, SSL / TLS, Linux (Kernel), Testautomatisierung, Python, Linux Entwicklung, TCP/IP

3/2006 – 10/2013

I worked 8 years in C and C++ under Linux. In this period I developed very different products: for embedded platforms, desktop applications and server side applications.
I have also developed drivers for in-house manufactured hardware. The hardware generally is for networking or VoIP solutions.
I developed protocols according to ITU-T and IETF standards, but also proprietary protocols created internally or by other manufacturers.
On the server side I have developed all kind of worker applications. I have worked with WEB and WEB services and databases.

The most important project at this job are:

1. HMI Touchscreen. GUI application for controllers/dispatchers to interact with Voice Communication System: Long life project with “Mission Critical” factor. It also includes subproject “Web based Drag and Drop HMI Designer”. The application communicates with different modules in the system (VoIP, call control, audio mixer, database).
• Project time span: summer 2007 - present
• Project stages in which I was involved: development, maintenance, collaboration with teams from Germany, Switzerland, Spain.
• Responsibilities during the project: lead programmer
• Technologies used: Implemented with C++ Linux, Qt/QML GUI library
• Challenges encountered: In order to achieve greater flexibility for functional and “GUI design” capabilities we developed our own GUI description language. Quality and performance are critical for this application.

2. Implementation of protocols according to ITU-T, IETF or proprietary documentation:
- SCCP and TCAP from SS7 stack;
- SUA, M2PA, M2UA, M3UA from SIGTRAN stack;
- H324M protocol (also optimization for specific hardware platform);
- MGCP/Megaco protocol;
- proprietary protocols for controlling radio stations from different vendors over IP/serial links;
- proprietary protocol for controlling SCADA equipments in the network;
- high performance ENUM and Service Discovery clients used by softswitch for call routing;
- high performance POP3 client and SMTP server used by softswitch to implement services like: email2sms, sms2email, voicemail2email, alerts2email, IVR2email;

• Project time span: March 2006 - 2013
• Project stages in which I was involved: requirement analysis, development, maintenance
• Responsibilities during the project: developer
• Technologies used: C/C++ Linux, PostgreSQL
• Challenges encountered: Need for deep understanding of many algorithms and mechanisms used in the protocol. Also there is additional complexity due to specific client API that needs to be offered.

3. Build and test automation system: I integrated software for build automation and implemented test automation logic for our continuous integration and testing system. The system under test is “Voice Communication System” that includes Media Gateways (E1, MFC, FXS/FXO, E&M, etc.), Radio Gateways, softswitch and databases. The testing system runs unit, application and system integration tests. Testing is not intrusive and simulates real life usage.

• Project time span: January 2013 - present
• Project stages in which I was involved: identifying the needs, development, maintenance, deployment
• Responsibilities during the project: developer, team leader, product owner (role)
• Technologies used: Jenkins, PHP, bash, Linux, Postgre SQL
• Challenges encountered: Optimize testing procedure in order to fully benefit from test automation. Runing not intrusive tests while still being able to detect and report failures proves to be complicated.

SQL, Embedded Linux, Debian, Qt, Python, C++, Bash (Shell), TCP/IP, RTCP (RealTime Control Protocol), VoIP, PHP