An example program that uses manifests to transfer a single file from the producer to the consumer.

CCNx Single File Manifest Transfer main page
CCNx.org

This is the CCNx Single File Manifest Transfer program, a simple example of how to build manifests from data (files) and recursively fetch them from a client. It includes a set of programs, with source code, to serve a single file with a manifest and retrieve said file. The objective is to demonstrate one way in which manifests can be built and used for transport. It is not intended to be the optimal way to transfer data using manifests. The topic of transport protocols and their interaction with manifests is a topic of ongoing research and development.

After building, this application consists of 2 programs:

• ccnxFileRepo_Server: Serves files out of a directory.
• ccnxFIleRepo_Client: Lists and retrieves files from the server.

This application needs the Distillery CCNx distribution installed on the system. Please install the CCNx Distillery by downloading it from GitHub, here, and building it according to the instructions there.

To run the tutorial programs you will need a CCN forwarder (metis or athena) running. We'll use athena for this example, but either would work.

Note: Metis does not support nameless object support.

Start by running athena, then the ccnxFileRepo_Server (to serve a single file) and then the ccnxFileRepo_Client to retrieve said file. It is recommended that you run the athena, ccnxFileRepo_Server and ccnxFileRepo_Client in different windows.

Compiling the application:

1. Set the CCNX_HOME environment variable to the location of your Distillery build. In zsh, for example, it might look like this: export CCNX_HOME=/path/to/CCNx_Distillery/usr

2. If you ran 'make all' when you built the CCNx_Distillery distribution, you should already have the binaries in your $CCNX_HOME/bin directory.

   If they are not there, you can run make ccnxFileRepo from the CCNx_Distillery directory.

3. At this point, the compiled binaries for ccnxFileRepo_Client and the ccnxFileRepo_Server should be built and exist in $CCNX_HOME/bin

4. Start a forwarder. Do ONE of the following:

   4a. Start the CCNx forwarder, metis_daemon: $CCNX_HOME/bin/metis_daemon --capacity 0 &

   4b. Start the CCNx forwarder, athena: $CCNX_HOME/bin/athena -s 0 &

5. Run the ccnxFileRepo_Server: Start the ccnxFileRepo_Server, giving it a directory path as an argument. $CCNX_HOME/bin/ccnxFileRepo_Server /path/to/file /path/to/repo/store ccnx:/published/name

6. Run the ccnxFileRepo_Client to retrieve the file "/path/to/file" from the server.

$CCNX_HOME/bin/ccnxFileRepo_Client ccnx:/published/name out.bin

NOTE: Do not run the ccnxFileRepo_Client with the same output file name as the server file. This will cause things to break.

• The ccnxFileRepo_Client and ccnxFileRepo_Server automatically create keystore files in their working directory.

• You can experiment with different chunk sizes and client receive buffer sizes by changing the values of ccnxFileRepoCommon_ServerChunkSize and ccnxFileRepoCommon_ClientBufferSize, respectively. Both of these are defined in ccnxFileRepo_Common.c.

If you have any problems with the system, please discuss them on the developer mailing list: ccnx@ccnx.org. If the problem is not resolved via mailing list discussion, you can file tickets in the issue tracker.

For any questions please use the CCNx mailing list. ccnx@ccnx.org

This software is licensed under the PARC Software License. See LICENSE File.