Most College of Engineering classrooms are equipped with dedicated whiteboard cameras for capturing what is written while recording and/or streaming a lecture.
In addition, using a tablet (e.g. Apple iPad, Microsoft Surface...) can be a good option for displaying what you write electronically online, while recording or streaming. For further information, refer to the Nexus Options for Using Slide Annotations via Writing Tablets document, and their video tutorial: Writing Tablets to Replace Whiteboards