Monitoring Iran's compliance will require on-site IEAE inspections. Obama's deal has more intrusive inspections procedures than the Agreed Framework with North Korea, but that doesn't mean the procedures are sufficient. There will be continuous monitoring of a few declared nuclear sites, but Iran will be able to delay inspections of disputed facilities for at least 24 days, which would give it time to sanitize a site.
The larger problem is that, like North Korea, Iran is a big country: If the government wants to hide something, it will likely succeed. Compliance depends on voluntary cooperation. Perhaps Iran will cooperate, but so far, it has not come clean with the IAEA about 12 existing "areas of concern" regarding the "possible military dimensions" of its nuclear program.
That is not a good sign. It suggests that Iran, like North Korea (or, for that matter, Iraq during the 1990s), is likely to play a game of cat-and-mouse with inspectors — and that if it does cheat, as North Korea did, the world will again discover it is too late to do anything about it.
When the Agreed Framework unraveled, the U.S. cut off some benefits to North Korea while offering fresh incentives for cooperation. South Korea continued to bankroll North Korea until a more conservative government took office in Seoul. Military action wasn't a serious option because war would have been too destructive.
The U.S. won't have any more leverage to compel Iranian compliance than it has had with North Korea. Iran will most likely reap the lion's share of economic benefits — gaining access to more than $100 billion in frozen oil funds — in the next six months. That windfall couldn't be revoked. And military action against Iran would become increasingly risky once the embargo on selling conventional weapons and ballistic missiles to Tehran is lifted.