I can immediately think of four relevant aspects: 1.) influx of foreign student in the program, 2.) location (I know of several master's programs that teach a semester each at different universities in different countries), 3) curriculum, is there attention for international aspects in the modules that comprise the program, and 4.) how internationally are the graduates employed.

"international propierty" shuld be a systemic one, depending on main educational process dimensions. A systemic structural approach to that problem could lead to consider factors like:

a) number of contries or nationalities represented in the students set and professor staff. Some indicators could be cultural differences. For example, if in a MSc programm there are representatives from several countries of Latin America, I think it should be considered less "international" than a programm, attended by students from Subsaharian Africa, China, India, and Scandinavian countries.

b) Programm content and formation results: how significant could be for differents countries or regions.

c) Are learning and teaching tools and methods adapted to national and/or cultural diversity?

d) If educational context is relevant, take in account location, and how diverse it is.

Here I am considering that concept of "international" is an "inter - nations" issue.

I recommend that you select a framework for the indicators. The Balanced Scorecard approach is the best framework. We have done a lot of work in higher education. The Balanced Scorecard has produced conculting, R&D projects, export of education and publications: 

Kettunen, J. (2004). Bridge building for the future of the Finnish polytechnics, Journal of Higher Education Outreach and Engagement, 9(2), 43-57.

Kettunen, J. (2008). A conceptual framework to help evaluate the quality of institutional performance, Quality Assurance in Education, 16(4), 322-332.

Kettunen, J. (2011). Strategy and quality maps in higher education, US-China Education Review, 8(2), 149-156.

there must be a curriculum names @ UNIONE