How was international involvement the same and different in Rwanda and Darfur?
The response of the international community to both crises was similar in that it was delayed and ineffectual. The UN took too long to act in any decisive manner or to stop the genocide. In the case of Rwanda, events happened much more quickly, in the span of about one month in April of 1994, so time was more limited in that case and sanctions would probably not have worked, but it would not have taken much in the way of UN peacekeeping authority to stop the killing.
In the case of Darfur, genocide continued for years while the world community dithered and debated. It was a long time before what was happening there was even deemed genocide. This is in part because Sudan is an exporter of oil, and China and the US both need that resource, and this made it difficult to get any decisive resolution through the United Nations about sanctions or much of anything else, and President Bashir had ample time to pursue his policy of depopulation.
One other key difference was that in the case of Rwanda, many of the perpetrators of genocide in that country have since been brought to justice, while in Sudan that is much less likely to ever happen.