Skip to main content

Operation modes

The fiskaltrust.Middleware can be operated in following operational environments:

operational-environments (click to enlarge)

Identification of the operational environment from the perspective of a POS operator:

hosted in-househosted in a different buildingdedicated hardware resourceprivately shared (hardware) resourceoperational environment
(e.g. on a cash register or local network server)
(e.g. in a data center)
(e.g. dedicated server)
(e.g. virtualised resources)
private cloud

Availability of supported operational environments is dependent on the market as shown in the following table:

operation modeATDEFRIT
on- & off-premiseavailableavailableavailableavailable
private Cloud
operated by a 3rd party
availableavailablenot available
generally supported, but not offered
private Cloud
operated by fiskaltrust
(by the fiskaltrust product SignatureCloud)
not available
due to legal restrictions *
(by the fiskaltrust product ChaîneCloud)

*In Germany, the fiskaltrust.Middleware must always be operated as a local component of the electronic recording system. For example, if the electronic recording system runs on a local Windows based cash register, the fiskaltrust.Middleware has to be operated on the same operational environment (this could be the same machine, or a local network server). If the electronic recording system is a SaaS solution operated in the Cloud, the fiskaltrust.Middleware has to be operated in the same data center.

Components of the fiskaltrust.Middleware

Regardless of the characteristics of the product, fiskaltrust.Middleware consists of several logical components. This chapter provides an overview on these components.

On-premise & off-premise installed components

The on-premise solution of the fiskaltrust.Middleware requires installation and configuration for the client. Below the most important components of the Middleware are illustrated:


iPOS Interface

The iPOS interface is part of the queue, a component of the fiskaltrust.Middleware. It enables the communication between the cash register and the fiskaltrust.Middleware and is identical for all supported countries (cross national).

The iPOS Interface offers three interface methods:

  • echo (check availability),
  • sign (sign receipt data, send special receipts) and
  • journal (export data).

More detailed information, including the data flow, you can find in the communication chapter.


In addition to enable the communication with the cash register via iPOS Interface, the queue also serves to encapsulate the functionality of a receipt chain: All regular receipts created by the POS-System and sent to the fiskaltrust.Middleware are processed in the fiskaltrust.SecurityMechanism. This mechanism takes care of the creation of the unique, consecutive receipt number, the chaining and the persistence of the data. After getting secured and stored in the queue, the response of the fiskaltrust.SecurityMechanism is sent back to the POS-System. All special receipts (for example the periodical closings) are sent as "requests to execute a special function" to the fiskaltrust.Middleware and get responded by it.


The SCU (Signature Creation Unit) handles the country-specific implementation of the security solution and is responsible for the signatures.

The additional security and functionalities based on local market regulation is delivered by third party vendors (e.g. a software-based cloud solution, a hardware device, or a certificate), supported by fiskaltrust via the SCU. The choice of the SCU has impacts on the fiskaltrust.Middleware configuration, therefore available SCUs, its configuration, functionalities and limitations regarding the fiskaltrust.Middleware are documented in the appropriate appendices of the markets.

For specific information regarding supported Signature Creation Units and platforms, please refer to the appropriate appendices:

Helipad Helper

The Helipad Helper is used to support updates and configurations.

Hardware requirements

For the operation of the installed components of the fiskaltrust.Middleware following minimum hardware requirements are recommended:

HardwareMinimum requirements
General hardware requirementsThe fiskaltrust.Middleware can be generally operated on a Raspberry PI 2.
Local storageAround 500 MB (200 MB for the Middleware components + 200 MB reserved for update-packages); optional: storage for SQLite db (around 8-10Kb/receipt)
Hardware connectivityFor the German market: USB, SD, Micro-SD or COM port for a local hardware-based security device (Technische Sicherheitseinrichtung, TSE).
For the Austrian market: USB port
Internet connectivityOptional, but strongly recommended: (WIFI)modem for Internet connectivity to use software-security-, data as a service-, backup,- or configuration-/update services.

Supported software platforms

For detailed information on supported platforms and its restrictions, please refer to the linked appendices of the applicable markets in the table below:

Androidnot supportedsupportednot supportedsupported

ARM Processor

From version 1.3.39 it is now possible to run the the fiskaltrust.Middleware on ARM processors.

SCUARM 64 bitARM 32 bit
A-Trust Cloud TSEsupported but not testedsupported but not tested
Deutsche Fiskal Cloud-TSEsupported but not testedsupported but not tested
Diebold-Nixdorf Hardware-TSEnot supportednot supported
Epson Hardware-TSEnot supportednot supported
fiskaly Cloud-TSEsupported but not testedsupported but not tested
Swissbit Cloud-TSEsupported and testedsupported and tested
Swissbit Hardware-TSEunsupportedsupported and tested


The Launcher is a software (file) named fiskaltrust.exe, which is used only for the on-premise installed products (e.g. AT product fiskaltrust.SignatureCloud). For Windows, it is a .NET command-line application and a .NET Windows service. For Linux and Mac, the launcher can be executed via Mono, version 3.2.8 or higher, or used as daemon.

The main tasks of the launcher are:

  • providing basic configuration settings such as ftCashBoxId and access token
  • comparing the configuration data retrieved from fiskaltrust.Helipad with the local configuration
  • updating queue- and SCU packages accordingly to the configuration
  • execution of configured packages
  • load balancing of multiple queues

The executable file fiskaltrust.exe and the corresponding DLLs can be distributed via copy-paste and then configured and installed with the help of a command-line parameter. The launcher can be downloaded (incl. configuration) from the configuration page of the fiskaltrust.Portal, or found on and configured manually.

Call parameter of the launcher are documented in the chapter installation.

Private cloud (operated by a third party) installed components

No installation or configuration is required for the client and any platform can use this service. The availability and use of SaaS installed components is dependent on local regulations and currently available for Austria and Germany. In Germany, because of different market regulation, the fiskaltrust.Middleware components must be hosted and operated by the PosCreator in the same datacenter where the receipt generation process of a distributed point of sale system occurs.

The components for the SaaS solution are the same as for the local solution; except the launcher, which is not needed. In Germany, the fiskaltrust.Middleware components can be delivered by a predefined Kubernetes Namespace which can be deployed by a Helm-Chart. fiskaltrust provides a "Backend POD" Docker image and Helm-Charts to be deployed at the PosCreators environment.

Private cloud (operated by fiskaltrust) installed components

No installation or configuration is required for the client and any platform can use this service. This service is currently available in Austria and France.