#+title: Community-Lab: A Community Networking Testbed for the Future Internet

* Introduction
Hello, I'm Blah Blah from Blah Blah, I work at the CONFINE project and I'm
going to talk you about *##* Community-Lab, a community networking testbed for
the future Internet.
** Community networks
- Infrastructure deployed by organized groups of people for self-provision of
  broadband networking that works and grows according to their own interests.
- Characteristics: Open participation, open and transparent management,
  distributed ownership.
- The EU regards CNs as fundamental for *##* the universalization of broadband
  networking.
- Means new research challenge: How to support the growth and sustainability
  of CNs by providing the means to conduct experimentally driven research. *##*

** The CONFINE project: Community Networks Testbed for the Future Internet
- The CONFINE project takes on the previous challenge.
- Project supported by the European Community Framework Programme 7 within the
  Future Internet Research and Experimentation Initiative (FIRE).
- Partners: (*##* community networks) guifi.net, Funkfeuer, Athens Wireless
  Metropolitan Network; (*##* research institutions) Universitat Politècnica de
  Catalunya, Fraunhofer Institute for Communication, Information Processing
  and Ergonomics, Interdisciplinary Institute for Broadband Technology; (*##*
  supporting NGOs) OPLAN Foundation, Pangea. *##*
- Objective: Provide a testbed and associated tools and knowledge for
  researchers to experiment on real community networks. *##*

** Testbed?
- Environment built with real hardware for realistic experimental research on
  network technologies. *##*
- Some wireless testbeds, both indoor and outdoor.
  - Problems: their limited local scale, their unrealistic controlled
    environment, experiments can't share resources simultaneously.
- Internet: PlanetLab, planet-scale testbed with resource sharing on nodes.
  Main inspiration for Community-Lab. *##*

** Community-Lab: a testbed for community networks
- Community-Lab is the testbed developed by CONFINE.
- Integrates and extends the participating community networks.
# Place CN logos over green blobs of CONFINE logo,
# with FEDERICA logo in center blob.
- Using the FEDERICA research backbone for interconnection. *##*
- All Community-Lab's software and documentation is “free as in freedom” so
  people can use it to setup their own CONFINE testbed.

* Requirements and challenges
A testbed has requirements that are challenged by the unique characteristics
of CNs.  For instance, how to *##*

** Simple management vs. Distributed node ownership
- manage devices belonging to diverse owners? *##*

** Features vs. Lightweight, low cost
- support devices ranging from PCs to embedded boards? *##*

** Compatibility vs. Heterogeneity
- work with devices which allow little customization?
- support diverse connectivity models and link technologies including
  wireless, wired and fiber? *##*

** Familiarity & flexibility vs. System stability
- Researchers usually prefer a familiar Linux env with root access.
- isolate experiments that share the same node?
- *##* Sometimes accessing node locations can be hard. *##*
  - keep nodes stable to avoid in-place maintenance? *##*

** Flexibility vs. Network stability
- Remember that network experiments run on a production network.
- allow interaction at the lowest possible layer of the CN while not
  disrupting or saturating it? *##*

** Traffic collection vs. Privacy of CN users
- allow experiments performing traffic collection and characterization?
- While avoiding researchers spying on users' data? *##*

** Management robustness vs. Link instability
- deal with frequent network outages in the CN when managing nodes? *##*

** Reachability vs. IP address provisioning
- CNs have IPv4 scarcity and incompatible addressing with little IPv6 support.
- support testbed spanning different CNs? *##*

* Community-Lab testbed architecture
** Overall architecture
This is the architecture developed by the CONFINE project to handle the
previous challenges.  It applies to all testbeds using CONFINE software. *##*

- A testbed consists of a set of nodes managed by the same server. *##*
  - Server managed by testbed admins.
  - Network and nodes managed by CN members.
  - Node admins must adhere to testbed terms and conditions.
  - This decouples testbed management from infrastructure ownership & mgmt. *##*
- Testbed management traffic uses a tinc mesh VPN:
  - Avoids problems with firewalls and private networks in nodes.
  - Uses IPv6 to avoid address scarcity and incompatibility between CNs.
  - Mgmt connections are short-lived to tolerate link instability. *##*
- Gateways are entry points to the mgmt network.
  - They help extend it over multiple CNs by external means (e.g. FEDERICA, the
    Internet).
  - They can also route the management network to the Internet. *##*
- Researchers run experiments in slices spread over several nodes (as
  slivers). *##*

** Slices, slivers and nodes
- These concepts are inspired in PlanetLab.
- A slice is a management concept that groups a set of related slivers.
- A sliver holds the resources (CPU, memory, disk, bandwidth, interfaces…)
  allocated for a slice in a given node.
- A node hosts several slivers at the same time. *##*

** Node architecture
allows the realization of these concepts.  *##* A node consists of a CD, a RD
and a rD on a wired local network. *##*

- The community device
  - Completely normal CN device, so existing ones can be used.
  - routes traffic between the CN and the local network (which runs no routing
    protocol). *##*
- The research device
  - Usually more powerful than CD, since experiments run here.
    - Separating the RD from the CD minimizes tampering with CN infrastructure.
    - Also experiments can't crash CN devices.
  - runs the versatile, light & free OpenWrt distro, customized by CONFINE. *##*
    - Slivers are implemented as lightweight Linux containers.
    - So researchers get root access to a familiar environment. *##*
  - provides direct interfaces to allow low-level interaction of experiments
    with the CN bypassing the CD. *##*
  - runs CONFINE control software
    - uses LXC tools to manage containers and enforce resource limits,
      isolation and node stability.
    - uses traffic control, filtering and anonymization to ensure network
      stability, isolation and privacy (partialy implemented). *##*
- The recovery device (not implemented) can force a remote hardware reboot of
  the RD in case it hangs.  It also helps with upgrade and recovery. *##*

* Experiments support
# Tag diagram with new title.
Researchers can configure slivers with different types of network interfaces
depending on the connectivity needs of experiments.  For instance, to *##*

- mimic a home PC: use the private interface, *##* which has L3 traffic
  forwarded using NAT to the CN but filtered to ensure network stability. *##*
- implement a network service: create a public interface, *##* which has a CN
  address and L3 traffic routed directly to the CN but filtered to ensure
  network stability. *##*
- experiment with routing algorithms: create an isolated interface, *##* which
  uses a VLAN on top of a direct interface.  All L2 traffic is allowed, but
  only between other slivers of the same slice with isolated interfaces on the
  same physical link.

These were demonstrated with BitTorrent and mesh routing experiments at IEEE
P2P'12 Conference.  *##* Future support is also planned for experiments that:

- analyze traffic: create a passive interface *##* to capture traffic on a
  direct interface, which is filtered and anonymized to ensure network
  privacy. *##*
- perform low-level testing: *##* the sliver is given free raw access to a
  direct interface.  For privacy, isolation and stability reasons this should
  only be allowed in exceptional occasions. *##*

Besides experiments run in slices, researchers will soon be able to collect
link quality and bandwidth usage measurements of all RDs' interfaces through
the DLEP protocol. *##*

Moreover, the server and nodes will soon publish management information
through an API that can be used to study the testbed itself, or to implement
external services like node monitoring and selection.

** An example experiment
to show how the testbed works.  We'll create two slivers which ping each
other. *##*

1. The researcher first contacts the server and registers a slice description
   which specifies a template for slivers (e.g. Debian Squeeze) and includes
   data and programs to setup slivers and run experiments. *##*
2. This and all subsequent changes performed by the researcher are stored in
   the registry, which holds the config of all components in the testbed. *##*
3. The researcher chooses two nodes and registers sliver descriptions for them
   in the previous slice.  Each one includes a public interface to the CN.
   Then the researcher tells the server to instantiate the slice. *##*
4. Each of the previous nodes gets a sliver description for it.  If enough
   resources are available, a container is created by applying the sliver
   configuration over the selected template. *##*
5. Once the researcher knows that slivers have been instantiated, the server
   can be commanded to activate the slice. *##*
6. When nodes get instructions to activate slivers they start containers. *##*
7. Containers execute the setup & run programs provided by the researcher. *##*
8. Researchers interact straight with containers if needed (e.g. via SSH) and
   collect results from them. *##*
9. When finished, the researcher tells the server to deactivate and
   deinstantiate the slice. *##*
10. Nodes get the instructions and they stop and remove containers. *##*

This is a summary of all the previous steps. *##*

* Cooperation between community networks and Community-Lab
can take different forms.  Given a typical CN like this, with most nodes
linked using cheap and ubiquitous WiFi technology: *##*

- CN members can provide an existing CD and let CONFINE connect a RD to it via
  Ethernet.  Experiments are restricted to the application layer unless the
  node owner allows the RD to include a direct interface (i.e. antenna). *##*
- CN members can provide a location and let CONFINE set up a complete node
  there (CD and RD).  In this way CONFINE helps extend the CN. *##*
- CONFINE can also extend the CN by setting up a physically separated cloud of
  connected nodes.  Experiments in all layers are possible in this setup, but
  users should be warned about the research nature of the network. *##*

These are only a few ways of cooperation, but more can be envisioned. *##*

* Participate!
We introduced you to Community-Lab, a new testbed being developed by the
CONFINE project to support research that can help CNs become a key part of the
Internet in a near future.

More information: http://community-lab.net/, http://confine-project.eu/

Community networks and researchers: We look forward to your participation!

Questions? Thanks.

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