Okay, I hate to argue with the USPS, but no one actually uses all caps. NO one. Maybe computer-generated mailing lists, but no one else. Also, the site Copyright linked to has no commas anywhere in the address. The most common way to address mail is as so:
Jane L. Miller
1960 W. Chelsea Ave. Ste. 2006
Allentown, PA 18104
Not all address have the "plus four" zip code, but if there is one it's generally separated by a hyphen as so:
Allentown, PA 18104-1271
There is no comma between the state and the postal code.
Also, it is still permissible to spell out the name of the state (Allentown, Pennsylvania 18104). The post office does prefer the two-letter codes, but spelling out the state is better than guessing and using the wrong abbreviation.
If you send first-class mail, USPS recommendations (post 2) are just that: recommendations. You can address the item any way you want. They are legally required to do everything within their power to deliver it. If your address can't be read by machines, so the item has to be handled by people, it may arrive a day later than it would otherwise - but that's all.
If you take advantage of lower rates such as bulk mail, their rules are absolute. They can refuse to deliver your mail or charge you first-class postage for it. Since people who use these rates tend to also use computers to address their mail, this is not a problem in practice.
I suspect that most people who ask this question on WRF send first-class mail. In that case, my experience is that the format of post 3 is most common.
In AE there is no comma before the zip code.
There is no need for a period either.
As an aside, I find it strange that the company name and address are written on only one line.
I would expect the letterhead to be in the following format (perhaps with the company name in all caps): Jinglin Pvt. Ltd. Janakpuri District Center
Janakpuri, New Delhi 110044