Agile software methodology is beneficial in large & distributed projects. In large projects synchronizing work between different teams & distributed sites is main challenge in Agile adoption. Meaningful communication, consistent communication structure, collaboration, test driven design and continuous integration are the key factors that would improve productivity, reduce project risk, and enhance software quality.
Divide the teams into small sizes (4-7). Code delivered at the conclusion of each time-box at each level must be "complete," meaning it can be built locally (that is, a build supporting the work just for that team), passes local QA, can be built in the "master build" spanning all teams, and passes all unit and integration tests.
Teams deliver to a fixed schedule, only allowing variance in the volume of functionality delivered. Teams may not vary the time box to get an ‘extra' feature in a release. Features, even those planned for a particular release, may slip to a subsequent release but completed code is always released at the planned times. As a result, delay is minimized whilst integrity is maximized.