Installing Additional SAMI Tools

The Secure and Accountable Measurement Infrastructure (SAMI) is a collection of software tools designed to aid researchers and engineers in managing internet measurements from various vantage points within the internet. This document describes how to install additional tools into the SAMI infrastructure. For general information on SAMI, please see the SAMI overview document.

Please note that in this document, INSTALL_DIRECTORY represents the SAMI root directory, and SRC_DIRECTORY represents the directory where the SAMI source was untarred.

Invocation Script

One of SAMI's strengths is that it treats the actual measurement tools, e.g., ping, traceroute, httperf, etc., as external modules. This is accomplished by providing a standardized API in the form of a wrapper script between the tools and the SAMI software. It is this wrapper script that the SAMI probe actually calls, e.g., ping-script, traceroute-script, or httperf-script. The wrapper script must provide the minimum functionality necessary to allow a measurement request.

Developing the appropriate invocation script for a new tool is required before the tool can be installed. The easiest way to accomplish this is to edit one of the pre-existing scripts to support the new tool. The wrapper scripts are found inSRC_DIRECTORY/src/tools.

Propagating the New Tool and Invocation Script

Although not absolutely necessary, the new tool should be built under every O/S release on the SAMI probes within the pertinent CPOC's administrative domain. Then install the appropriate build of the tool, the invocation script, and the tool's configuration file ( which lists the version number of the tool ) into the O/S release tools directory on the CPOC, e.g.,: INSTALL_DIRECTORY/tools/FreeBSD-4.10-RELEASE.

See the CPOC Usage document for more details on the O/S release tools directory on the CPOC.

Issuing a SIGHUP on the CPOC initiates the process which downloads the new tool to the SAMI probes.

Setting Policy for the New Tool

The new tool must be included in the resource-map file in the akenti subdirectory ( please see the CPOC Usage document for more details on the resource-map file. ) Additionally, if the new tool will require a different policy than that provided by its parent within the Akenti resource tree, then a Policy certificate for the new tool's sub-tree must be created, along with the Use Condition certificate(s) that will specify the new constraints for this tool. ( Please see for details in creating Policy and Use Condition certificates. )

Note that due to limitations in Akenti, the cpocd will need to be restarted if additional certificates are added or altered. Moreover, the addition of a new entry in the resource-map file may also require a reboot of the cpocd.