The implementation of peer-to-peer in flash crowds: A case study of bandwidth and cost reduction for over-the-air updates

Abstract

This thesis will examine the plausibility of exchanging protocol from a normal
server-client to a peer-to-peer solution for over-the-air updates, using a single case
study for Sony Mobile Communications AB in Lund, Sweden. It will examine the
effort, the risks, and what the actual gain may be comparing to a client-server
approach for over-the-air software updates. Sony Mobile today uses a content delivery
network which creates a peak upon new releases of software and this thesis
will examine how efficient the peer-to-peer approach is for flash crowds in terms of
saved data from the content delivery network. Continuing on the problem there
are several global network infrastructure limitations, such as NAT44, NAT444 and
firewalls, which proves to decrease the overall connectability of peers in peer-topeer
networks. Live experiments using real mobile devices from Sony Mobile will
be used to examine the gain after a comprehensive literature study to explore what
impact such network limitations has on peer-to-peer networks. As a consequence
showing that even with limitations there is a potential gain of changing the approach
to a peer-to-peer model. The live experiments prove that with few steps there can be a potential data saving gain up to 20%, without any interference
with the global infrastructure. The findings will also prove the feasibility of additional hole punching techniques which may further push the gain towards higher
numbers.

Popular Abstract

As from ancient history, sharing a burden have always ensured that a task can be
completed much quicker than doing it entirely by yourself. Columbus would not
have made it to the West Indies without the help of his crew, and the same applies
for over-the-air software updates to actively reduce data flow from a server, and
by doing so reducing costs by up to 40%!

Peer-to-peer, a solution which can be easily described with a pub environment,
where all the pub-people speak out and everyone listens at the same time.
Information is shared to all without a central entity in between. Over-the-air software updates are spread globally whenever a mobile receives a fresh version of
the operating system. This is usually followed by a craving of having the latest
by the end-user which results in a flash crowds. Flash crowds, as a phenomenon,
resembles ants going after sugar. This flash crowd puts a normal server structure
under a lot of strain. It is as well costly as all the downloads must be paid for by
the manufacturer. By distributing the effort to the mobile devices themselves, the
data flow reduces by 17%, which actively translates to a cost reduction of the same
magnitude. This is just by changing the way of communication, from a monologue
to a dialogue for the mobiles. However, there are some drawbacks. In the global
Internet, public IP-addresses are being used in extent and to many devices are
today connected. Consequently, now even IP-addresses are shared among many
devices.

Returning to the pub scenario, imagine that you need to talk to a stranger
which has your hat, because you throw it in the air when your favorite song
came on. However, to reach this stranger you must firstly pass a bouncer, as
the stranger is within a restricted area (private network). The bouncer acts as a
network address translator (NAT) and tells you whether you may pass or not, if
you know this stranger you can tell the bouncer this and he will let you through.
If you do not, then you will be blocked and the bouncer will just throw away your
request.

To deal with such bouncers on the Internet, hole punching techniques have
been introduced. A hole punching technique is, with common predetermined rules
in the pub and with the bouncer’s attention, you passing the line and entering the
restricted area to the stranger and successfully retrieving your hat. This mutual
agreement between you (mobile device), the pub (the Internet), and the bouncer
(NAT) represents the hole punching technique Universal Plug and Play, or just UPnP. Consequently, with UPnP the 17% reduction can increase and reach levels
towards 40%, which is the ideal scenario where all the pub-people can freely speak
to anyone without restricted areas. Actively increasing the amount of friendly
faces willing to share the software updates with you.

The plausibility of transitioning towards a peer-to-peer model from a normal
client-server approach not a large effort for any mobile manufacturer. The conclusion
is that even with obstacles present around the world, just as with the
restricted areas in the pub, it is with little effort of implementation a cost reduction can be obtained when new versions are released online. Any manufacturer
trying to reduce costs should look no further than towards peer-to-peer with additional hole punching techniques. Such a transition means very little effect on
the mobile devices but actively reducing costs and releases strain on any server
structure which might be in place for any manufacturer.

• author: Matulaniec, Artur
• supervisor: Jens A Andersson
• organization: Department of Electrical and Information Technology
• course: EITM01 20171
• year: 2017
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: peer-to-peer, over-the-air, OTA, p2p, hole punching, NAT, IPv4, IPv6, economic gain
• report number: LU/LTH-EIT 2017-593
• language: English
• id: 8919033
• date added to LUP: 2017-06-28 15:53:29
• date last changed: 2017-06-28 15:53:29