SCION Java MultiPing

A tool that allows pinging / trace route) all known ASes in one run.

MultiPing provides several tools:

• Download Assignments for downloading a list of known ISD/AS assignment
• Ping All for sending a single traceroute to all known ASes along the shortest path (default behaviour)
• Ping Repeat for repeatedly probing (traceroute) multiple paths to multiple ASes.
• Ping Responder for responding to incoming echo requests.

Execution

All tools can be run from the executable jar file which is available in the GitHub Releases section. It can be executed with: https://github.com/netsec-ethz/scion-java-multiping/releases/download/v0.2.0/scion-multiping-0.2.0.jar

java -jar scion-multiping-0.2.0-executable.jar [tool-command]

Some tools require configuration files, see below in the tool description sections.
See also the troubleshooting section below in case of issues.

Download Assignments

The tool parses Anapayas ISD/AS assignment website and writes the result to a local file isd-as-assignments.csv. Note: the isd-as-assignments.csv output file can be directly used as input file for the PingRepeat

Ping All

The tool parses Anapayas ISD/AS assignment website, identifies the shortest path to each AS and sends a traceroute to each AS. It reports the number of paths to each AS as well as the shortest path with latency, remote IP, hop count and remote IP.

It also provides a summary of its findings.

Ping Repeat

The tool reads a list if ISD/AS codes from a csv file ( isdAsInputFile, example), repeatedly sends traceroute SCMP requests to each AS and writes the results to an output file ( outputFile, example).

SCMP request are sent in several rounds, each round consisting of several attempts. In the default configuration (see below) it will:

• execute 144 rounds (roundRepeatCnt)
• start a new round every 600s = 10 minutes (roundDelaySec)
• in each round, select the 20 shortest paths (maxPathsPerDestination) for each AS
• in each round, execute 5 "attempts" (attemptRepeatCnt)
• in each "attempt", send a single traceroute request along every selected path to every AS, then wait 100ms (attemptDelayMs) before executing the next attempt

144 rounds á 10 minutes results in a total runtime of about 24h.

Configuration

The tool uses a configuration file ping-repeat-config.json (example) that can contain the following arguments:

{
  "attemptRepeatCnt": 5,
  "attemptDelayMs": 100,
  "roundRepeatCnt": 144,
  "roundDelaySec": 600,
  "maxPathsPerDestination": 20,
  "tryICMP": false,
  "isdAsInputFile": "ping-repeat-destinations.csv",
  "outputFile": "ping-repeat-output.csv",
  "localPort": 30041,
  "consoleOutput": true
}

Input

The input file is a csv file with ISD/AS, label and IP (optional). The ISD/AS can optionally be enclosed in ". When an IP is given then the tool will execute an echo request to the IP, otherwise it will execute a traceroute request to the border router of the destination AS. Example:

64-2:0:9,"ETH Zurich (ETHZ)"
"64-2:0:4c","AWS PoC Anapaya",192.168.0.1

This will result in a traceroute request to th ETH border router of 64-2:0:9 and a echo request to 64-2:0:4c,192.168.0.1.

Execution

THe tool can be executed with:

java -jar scion-multiping-0.2.0-executable.jar ping-repeat

Output

The output file is a csv file with one row per round/path. Each row consists of:

• ISD/AS
• Remote IP (if known)
• Time stamp
• Type: can be ECHO or TRACE
• Result: can be SUCCESS, NO_PATH (no path found to destination), LOCAL_AS (the destination AS is the local AS) or ERROR
• Hop count of the path taken
• The path
• millisecond latency for each attempt (default: 5)

For example, this shows measurements for three paths to 64-0:0:ce7:

64-0:0:ce7,193.247.172.126,2024-09-13T15:46:04.044713600Z,SUCCESS,2,[2>6 19>9],14.54,14.38,13.86,13.23,14.86
64-0:0:ce7,193.247.170.170,2024-09-13T15:46:04.045213500Z,SUCCESS,2,[1>5 17>1],10.4,10.3,9.79,9.91,10.76
64-0:0:ce7,193.247.170.170,2024-09-13T15:46:04.045213500Z,SUCCESS,2,[2>6 17>1],10.7,10.3,9.98,9.86,10.75

This shows a LOCAL_AS and a NO_PATH event:

64-2:0:9,,2024-09-13T15:46:05.979346700Z,LOCAL_AS,0,[]
71-2:0:4a,,2024-09-13T15:46:16.554705200Z,NO_PATH,0,[]

Ping Responder

The PingResponder can be configured with a configuration file ping-responder-config.json, it has two options:

{
  "localPort": 30041,
  "consoleOutput": true
}

Troubleshooting

No DNS search domain found. Please check your /etc/resolv.conf or similar.

This happens, for example, on Windows when using a VPN. One solution is to execute the jar with the following property ( the example works only for ethz.ch):

java -Dorg.scion.dnsSearchDomains=ethz.ch. -jar scion-multiping-0.2.0-executable.jar