Aalto University

School of

Electrical Engineering

Liberouter:

Towards Do-It-Yourself Networking

Jörg Ott

Teemu Kärkkäinen

http://www.netlab.tkk.fi/~jo/

24 January 2014

Aalto University

School of

Electrical Engineering

Down-to-Earth Neighborhood Networking:

Localizing Content Sharing

• Keeping content where is matters

• Preserving an intuitive understanding of the sharing

context: people in the same place (at the same time)

Aalto University

School of

Electrical Engineering

1) Networking platform

2) Sharing applications

Aalto University

School of

Electrical Engineering

Do-It-Yourself…

Aalto University

School of

Electrical Engineering

Opportunistic Networking

• Think messages, not packets

• Discover peers

• Exchange upon an encounter (“contact”)

WLAN

Bluetooth

…

Aalto University

School of

Electrical Engineering

Opportunistic Networking

• Think messages, not packets

• Discover peers

• Exchange upon an encounter (“contact”)

• Store (and carry), forward (replicate)

• Takes time, messages may disappear (best effort)

• Performance = f(node density, mobility, …)

WLAN

Bluetooth

…

Aalto University

School of

Electrical Engineering

Networking abstractions

• Direct device-to-device with low latency (IP)

• Direct and multi-hop Messaging (Bundles)

• Publish / subscribe mechanism – Applications register interest in content using metadata

– Matching content will be delivered

• Search – Enable complex message queries against stored content

– Based upon metadata description (generic matching)

• Floating content model – Spreading content in a limited area only [www.floating-content.net]

– Defined by (location, radius, content lifetime)

Aalto University

School of

Electrical Engineering

Applications: API and Distribution

SCAMPI Router

Search Unicast Pub/Sub

Storage

Peer Discovery Transport

Native API

TCP

Pla

tform

-independent

(needs J

VM

)

Native Apps

Pla

tform

-

specific

HTML5 Shim

HTML5

App

HTML5 App

Distribution

install install

Pla

tform

-

independent

Aalto University

School of

Electrical Engineering

Mobile devices alone may not be enough

• Device-to-device communication is tricky

– Mobile OSes and APIs designed for connecting to infrastructure

• How to bootstrap mobile devices?

– Want to avoid dependency on the web

• Just using people’s mobiles may not be very reliable

– Fluctuation in device density during the day, week, year

– Potentially shorter range, battery constraints

• More predictable storage locations desirable

– Apps need to keep their data somewhere

Aalto University

School of

Electrical Engineering

Liberouter

• Basic features – WLAN access point

– Captive portal

– SCAMPI router

– Storage node

– Can mesh with other liberouters

Raspberry Pi

WLAN i/f

USB flash drive

8 GB system SD card

Total: ~80 EUR

Aalto University

School of

Electrical Engineering

Liberouter

• Basic features – WLAN access point

– Captive portal

– SCAMPI router

– Storage node

– Can mesh with other liberouters

• Applications – Android liberouter distribution

– Native SCAMPI (Java) applications

– HTML5 SCAMPI-enabled

– HTML5 legacy

• Web Access – Local instance of the distributed app store

– Content interface: browsing (and interaction)

– Instrumenting non-SCAMPI nodes for forwarding

Aalto University

School of

Electrical Engineering

Component List - Raspberry Pi

- USB WiFi …

Software - SCAMPI Route

- Linux Distro

DIY Instructions - Building

- Configuring

Misc - 3D Printed Covers

- Power Options

EVERYTHING ONLINE

Aalto University

School of

Electrical Engineering

Aalto University

School of

Electrical Engineering

1) Networking platform

2) Sharing applications

Aalto University

School of

Electrical Engineering

Deploying applications

• Web Apps (HTML5)

– Limitations due to frameworks

– Require always-on Internet connectivity

• App Stores (native)

– Native apps: access to device features

– Store operator as a gatekeeper

+ quality control, trust

− Internet dependency, delay, potential censorship

• An app is nothing but a (signed) bag of bits

– Use messaging for distribution

Aalto University

School of

Electrical Engineering

SCAMPI Apps

Aalto University

School of

Electrical Engineering

SCAMPI Apps

Aalto University

School of

Electrical Engineering

Remember: This is NOT the Internet!

• Distance matters: focus on proximity

• Not necessarily instant feedback about success/failure

• Don’t try to compete with the Internet

– Emphasis is on different paradigms

• Applications operate invisibly in the background

• Respond immediately upon user attention

• Completeness, congruence & repeatability not essential

• Provide value-add with probabilistic operation

• Reflect this in the UI

Aalto University

School of

Electrical Engineering

Simple Messaging & Sharing Apps

Aalto University

School of

Electrical Engineering

Distributed “Google People Finder”

Aalto University

School of

Electrical Engineering

spacetimenetworks.com

Building infrastructure-free communication networks in challenging environments.

Aalto University

School of

Electrical Engineering

Conclusion

• Exploring less dependency on Internet services

• Building own networks of limited reach and scale

• Suitable for a range of information sharing applications

• Currently exploring

– More diverse (outdoor) applications

– Application authoring

– Mutable contents, distributed editing, and merging

– Limited real-time elements

• Do try this at home!

http://www.ict-scampi.eu/results/scampi-liberouter/