Combine the sugar and the port in a Dutch oven. Bring to a boil, and cook for 4 minutes or until the sugar dissolves. Add the cranberries, orange juice, ginger, and garlic, and cook over medium heat until reduced to 3 cups (about 20 minutes). Press the cranberry mixture through a fine sieve over a bowl, discarding solids.
Note: Cranberry Syrup can be stored, covered, in refrigerator up to 1 week.