Python implementation of SCION, a future Internet architecture.

• doc/ contains documentation and specification of the SCION implementation
• infrastructure/ contains the code of the SCION infrastructure elements (servers, routers)
• lib/ contains the most relevant SCION libraries
• topology/ contains the scripts to generate the SCION configuration and topology files, as well as the certificates and ROT files

Necessary steps in order to run SCION:

1. Make sure that ~/.local/bin can be found in your $PATH variable. For example, do the following to update $PATH in your ~/.profile and apply the changes to your session:

   echo 'export PATH="$HOME/.local/bin:$PATH"' >> ~/.profile && source ~/.profile

2. Install required packages with dependencies:

   ./deps.sh all

3. Configure the host Zookeeper instance. At a minimum, add maxClientCnxns=0 to /etc/zookeeper/conf/zoo.cfg, but replacing it with docker/zoo.cfg is recommended. This has the standard parameters set, as well as using a ram disk for the data log, which greatly improves ZK performance (at the cost of reliability, so it should only be done in a testing environment).

4. Create the topology and configuration files (according to topology/Default.topo):

   ./scion.sh topology

   The resulting directory structure will be created:

    ./gen/ISD{X}/AD{Y}/
        {elem}{X}-{Y}-{Z}/
            ad.yml
            path_policy.yml
            supervisord.conf
            topology.yml
            certs/
                ISD{X}-AD{Y}-V0.crt
                ISD{X}-V0.trc
            keys/
                ad-sig.key
   

5. Run the infrastructure:

   ./scion.sh run

6. Stop the infrastructure:

   ./scion.sh stop

Notes about topology/Default.topo:

• defaults.subnet (optional): override the default subnet of 127.0.0.0/8.

• core (optional): specify if this is a core AD or not (defaults to 'false').

• beacon_servers, certificate_servers, path_servers, dns_servers (all optional): number of such servers in a specific AD (override the default value 1).

• links: keys are ISD_ID-AD_ID (format also used for the keys of the JSON file itself) and values can either be PARENT, CHILD, PEER, or ROUTING.

In order to run the unit tests:

./scion.sh test