By open-loop simulations I mean set up a fully automated strategy with real-time input and paper trade on it for awhile. I am a trading novice (complete), but am a programming and numerical analysis professional. Designing trading systems looks like a fun diversion when I'm not playing poker. What I want to do in the first cut is simply: 1) Access real-time quotes from C++. It looks like interactive brokers has a C++ API. Are there more that offer this kind of service? I prefer to write my own software rather than use some kind of canned packge. IB makes a big deal of requiring you to be an experienced trader in their application. If I admit I am a novice, will they deny my account? If I lie, will they try to verify by calling me up and realizing I don't know a damn thing? Eventually I'd like to close the loop and trade a system, but that's awhile down the road. For now, I just want to tinker with system for awhile to get a feel for the process. I've already got a backtesting setup going smoothly, so the next step is a dry run on incoming data. Any help appreciated.