It can be worthwhile checking for firmware or software updates for your various electronic devices. Doing so the other day I discovered that my HP LaserJet Pro P1102w Printer has added support for Apple AirPrint and Google Cloud Print. A 5MB download later, and it was time to explore the cloud.
I now have ePrint! HP have been promoting the ePrint feature for their new printers for a while now, and without much fanfare have added it to some already released models. I couldn't find a comprehensive list of what printers it is available on - the lists I did find did not include my printer - so the most reliable method might be to check the HP Support site and look at the recent firmware changelogs for any printers of interest.
At this stage, you're probably wondering what ePrint actually means. The HP flash-ridden promotional site doesn't give much away. From what I can tell, the only feature of interest to me is that my printer now has an email address to which I can send emails, pictures and documents. For a smartphone this could be useful, but for a laptop or PC you'll prefer to print the normal way with all of the printer configuration options available to you.
ePrint also means that Google Cloud Print is fully integrated into the printer. After a minute of setup to associate my printer with my Google Account I was able to print from Google Docs on my smartphone. Since I'll only be printing when I'm at home near my printer, where I also have a PC available, this isn't actually that useful at the moment. However, it could be the start of a whole new way a printing, where the hassle of requiring a printer driver for each new printer is eliminated. It seems obvious that installing printer drivers onto smartphones is silly, so it's great that we can avoid that aspect but still be able to print.
So how does Google Cloud Print work? Google provide plenty of documentation on how to use it. Happily, if you know where to look you'll also find Google Cloud Print API - Receiving Print Jobs, where you can learn how it operates behind the scenes. I was curious how a print job from my smartphone, being passed to Google in the cloud, was able to get through my firewall to initiate the job on my printer. It turns out that the printer establishes a persistent connection to Google's print servers via XMPP, the protocol which originated with Jabber for instant messaging. Print jobs are then able to be pushed to the printer as soon as they arrive. The API documentation also explains that when printers register themselves with Google Cloud Print they must announce their capabilities.
Although printing through the cloud is not immediately useful to me, I am appreciative that the technology exists. I can imagine that the ability to print from a smartphone where no "real" computer is available could be very useful, especially as smart phones get smarter and the need for another computer are lessened. I am also happy that HP has added such a major feature as this to enhance a printer that I have already purchased. They were under no obligation to do so, but it does make me much more liable to purchase another HP printer when the need arises.