Frequently Asked Questions

This section provides frequently asked questions concerning SIL Kit and the corresponding answers.

Data Generation & Transmission

Is there a maximum payload size for Ethernet frames?

The size of the payload of Ethernet frames is not limited by SIL Kit. Nonetheless, the maximum payload size might be constrained by the system resources available on the system on which SIL Kit is executed.

Is there a maximum payload size for Publish/Subscribe or RPC data?

The size of the data payload of the Publish Subscribe and RPC service are not limited by SIL Kit. Nonetheless, the maximum payload size might be constrained by the system resources available on the system on which SIL Kit is executed.

Can I use a DBC file to generate CAN frames?

Within SIL Kit, there is no included support for DBC files. You can use SIL Kit enabled tools that have support for DBC files, or you will need to implement DBC support within your implementation yourself.

Setup

Is it possible to use statically configured ports for SIL Kit peer-to-peer communication between participants?

Since version 4.0.16 users can specify which port the participant opens for communication between participants by using the AcceptorUris field within the Middeware section of the participant configuration. By doing so, a firewall can be configured to allow these static ports for communication. The port used by the SIL Kit registry can be specified through its CLI.

What is the sil-kit-registry?

The SIL Kit registry is a central utility that is necessary for running a SIL Kit simulation. At the start, each participant connects to the registry and retrieves the connection information to all other participants. In this sense, the registry acts as a phone book that tells the user the contact information to all other participants of a SIL Kit simulation. The registry does not partake in the simulation itself. It especially does not route messages between participants. Please note that it is mandatory that all SIL Kit simulation participants can reach the SIL Kit registry for a proper simulation setup.

Can I use Vector SIL Kit together with real hardware/in a Hardware-in-the-Loop setup?

Vector SIL Kit was designed deliberately with Software-in-the-Loop environments in mind. Many aspects of it are designed for SIL settings (especially the virtual time synchronization, that adapts its speed to the execution speed of the participants) and not HIL settings. These aspects might imply that SIL Kit does not fit the needs of your hardware setup. Furthermore, SIL Kit itself does not provide capabilities to connect it to a hardware setup.

Nonetheless, some SIL Kit enabled tools may allow you to bridge a SIL Kit simulation and a HIL setup.

How can I interoperate a SIL Kit simulation that is distributed between Windows and Linux clients?

For SIL Kit it does not matter whether all simulation participants are running on the same kind of operating system. All SIL Kit simulation participants must be able to connect to the SIL Kit registry, and they must be able to establish a connection to all other simulation participants. In such a distributed setting, the SIL Kit registry must be started such that it is reachable through the network by other hosts.

You might do so by running the command below:

./sil-kit-registry.exe --listen-uri silkit://0.0.0.0:8501

Note

This example uses a different port, as a tool may have already opened a registry on the default port 8500.

All simulation participants must now specify a URI so that they connect to this registry (e.g., silkit://<IP of node running registry>:8501).

Other

How is the performance/latency/throughput of the SIL Kit?

The specific performance (latency, throughput, animation factor, etc.) of your SIL Kit simulation depends on a set of parameters that highly depend on your use case. The number of simulation participants, whether virtual time synchronization is used, the size of simulation steps, the size and frequency of messages being exchanged, and many other aspects highly influence the performance for you use case. Finally, the hardware being used, the network infrastructure and the distribution of simulation participants over different hosts affect the performance as well.

To get a first impression of the performance that can be expected of the SIL Kit in your use case, refer to the Benchmark Demo where you can specify a set of relevant parameters and get real performance measurements for your setup.

Can I control the order in which simulation participants execute their simulation steps, in case they occur at the same time?

No, the order simulation step execution of synchronized participants can not be controlled.

How can I configure a SIL Kit participant to write a trace log file?

A trace log file can be used in debugging scenarios to get a detailed insight into the execution of a SIL Kit participant.

The participant configuration is a YAML file which enables you to modify some aspects of the runtime behavior of SIL Kit simulation participants. In particular, you can also use it to let a participant generate a trace log file.

For example, by adding the following configuration:

Logging:
  Sinks:
  - Type: File
    Level: Trace
    LogName: TraceLogFile

Note

If your participant configuration already contains a logging section, you must only add the sink.

This will tell SIL Kit to write all log messages of Level trace and above to a file in the process working directory of the SIL Kit participant. The file name will be TraceLogFile with a time-specific suffix. The LogName field also supports an absolute path, e.g., LogName: C:\Temp\SimulationLog.

How can I use unicode characters with SIL Kit?

SIL Kit expects strings passed via the C and C++ API to be encoded as UTF-8. This is particularly important for paths, e.g., the path to the participant configuration.

This can lead to some confusion when SIL Kit is used on the Windows operating system.

The utility executables (sil-kit-registry, sil-kit-system-controller, and sil-kit-monitor), and all demo applications are compiled using a manifest, that automatically activates the UTF-8 codepage. This allows the correct handling of paths containing Unicode characters.

Even in modern Windows systems, UTF-8 is usually not used as the default codepage, in order to be compatible with old applications. Unfortunately this can lead to strange characters in the command line output of SIL Kit tools, when, e.g., the participant name contains non-ASCII characters.

As an example, when the participant name is set to 🚗 (car emoji), if the output codepage is not changed to UTF-8, the output might look like this:

Figure 20 : Mangled output from SIL Kit when the output codepage is not UTF-8, and the participant name contains Unicode characters

If the output codepage is changed to UTF-8 (see below), the output should look like this:

Figure 21 : Correct output from SIL Kit when the output codepage is set to UTF-8, and the participant name contains Unicode characters

If you use cmd.exe, run the command chcp 65001 before invoking any SIL Kit utilities or demos. This command changes the output codepage of the console window to UTF-8, which is required to correctly decode the text output of the executables for presentation in the console window.

If you use PowerShell, run [console]::InputEncoding = [console]::OutputEncoding = New-Object System.Text.UTF8Encoding before invoking any SIL Kit utilities or demos to achieve the same effect.