Announcing Nearby Connections 2.0: fully offline, high bandwidth peer to peer device communication

Posted by Ritesh Nayak M, Product Manager

Imagine walking into a hotel room and having the temperature set just right,
your favorite sub-genre of progressive-math-rock playing in the background, and
the TV urging you to continue binging on your saved guilty-pleasures watchlist.
What if your phone's contact book could expand to merge with your spouse's when
you're together, so you're never again put in the excruciatingly compromising
position of having to ask for your mother-in-law's phone number (which you ought
to have had on speed dial, in your favorites, and listed as an emergency
contact)? Now imagine a world where you can drive up to an empty driveway or
private parking space in a city like New York or San Francisco, and negotiate
with that space to rent it out until its owner returns.




The common thread among all these scenarios is being able to detect proximity to
-- and being able to communicate with -- people, places, and things "near" you.




At I/O this year, we spoke about a refresh to the Nearby
Connections API that can provide high bandwidth, low latency, encrypted data
transfers between nearby devices in a fully-offline P2P manner. Today we're
announcing the availability of
this API across all Android devices running Google
Play services 11.0 and up.




Nearby Connections uses WiFi, Bluetooth LE & Classic Bluetooth under the hood to
discover and establish connections to nearby devices. It abstracts away the
inherent complexity of these radios by leveraging the strengths of each, while
circumventing their respective weaknesses. Aside from the obvious advantage of
sidestepping the pain of dealing with the vagaries of these radios across
different OS versions and devices, this abstraction enables seamlessly upgrading
the bandwidth of a connection by switching between the radios as and when it
makes sense, as well as getting invisible over-the-air updates to use new radio
technology as it becomes available -- with no change whatsoever in the
application code.




At the heart of this API is a connection (with Unix-socket-like semantics) that
you can use to transfer bytes, files, or streams of data. There are two
supported connection topologies:

• Star: Useful for creating 1:N topologies where there's a centralized device
  that others are especially interested in. For example, the host of an offline
  game, or the teacher's device in a classroom quiz app.
  


• Cluster: Useful for creating M:N topologies that allow for creating looser
  mesh-like networks. For example, a classroom app that supports forming ad-hoc
  project groups for realtime collaboration, or an offline hyper-proximity-based
  chat app.

As a part of the process of building this API we worked with a few partners,
each with unique offline-data-transfer needs and environments. It's been great
to see what they've built on top of early versions of this API, and their
feedback has been invaluable in guiding us towards today's launch. Take a look
at some of the cool things they're building:

• The
  Weather Channel is building on-demand mesh networks in data-deficient areas
  to spread urgent weather warnings.
  


• Hotstar
  enables offline media sharing in places with spotty/no internet connectivity
  (like on public transportation, airplanes, etc.)
  


• GameInsight
  is using Nearby Connections to not only find nearby players, but also to run
  entire games offline.
  


• Android TV is building a remote control app (powered by Nearby Connections)
  to simplify initial setup, and to enable subsequent second screen experiences.
  

Now that the API is publicly available, we can't wait to see how you
will use Nearby Connections in your applications. To get started, visit
our developer
site, check our code
samples, and post any questions you have on Stackoverflow (tagged with google-nearby). To
stay up to date on the latest Android Nearby offerings (and our other
Context-related APIs), please subscribe to our mailing
list.