Remote Access


The TOPKAPI Vision SCADA Software offers extended remote viewing and command features from remote client stations without license (OPEN CLIENT option, low bandwidth use, screen display in one or two seconds through modem access) or using a basic Web browser (WEBSERV option, enabling implementation without any change inside the applications previously installed).
Communication can rely on the Internet, the Telephone Network (PSTN or GSM) and/or any TCP-IP network.


This module enables access to a TOPKAPI application using only a Web browser, and offers the following benefits :

  • No previous installation or setup of any application or services on the remote computer is required
  • No modification of the TOPKAPI application is required to publish it on Web browsers.
  • TOPKAPI's application changes are performed at a unique location (on the server), and do not have to be applied anywhere else


  • As for any other application which has to display complete graphic screens of good quality, the system is rather slow when using low bandwidth links (e.g. modem).
  • The user interface is a bit different from TOPKAPI itself, and some functions are restricted (e.g. graphs handling).

Using TOPKAPI Webserv is recommended when publishing information for many occasional persons or when access to the TOPKAPI application is required punctually or occasionally, from many machines without prior specific installation. Its use for operations requiring fast and sequenced access to several screens is limited to fast connections.


For example, a standby operator intervening remotely via a modem connection, and wishing to view 4 or 5 screens before making a remote command decision, will hardly accept a display time of 2 to 3 minutes (up to around 30 seconds for each screen).


AREAL pioneered access to the supervisor from remote client stations, and enhanced this technology over years.

With TOPKAPI, the benefits are:

  • Fast response time: a synoptic diagram screen displays and refreshes every one or two seconds in all circumstances, even with a modem connection.
  • The client station is a control station with a display and functions identical to the server station in all respects.
  • No maintenance constraints when modifying the server application: TOPKAPI offers the rare, and probably unique, ability to update automatically the application residing on the client station, without operator intervention

The drawback with specialized client technology is that a version of the software must be installed on each station likely to be connected to the supervision application.

The Open Client solution proposed by Areal enables free and unlimited installation of the light client software, access rights being provided by the server station. Based on TCP-IP, it can be used on the Internet, on the public switched telephone network, or on any private network

Use TOPKAPI Client whenever the supervision application, when viewing several screens, requires fast action in an environment identical to that of the main server station: typically, frequent remote control operations, mainly for standby duty operators.

You can use the Webserv and Open Client technologies together, for example when on the one hand data is viewed by many persons from the company or the general public, and on the other hand, control operations are performed by remote operators (nomad, standby, etc.)

Please also note that TOPKAPI can be used as a server for the TS Terminal Services technology: see TS Client.

Terminal Services can be compared to Web server solutions in regards with performance and centralized maintenance.

With TOPKAPI, it is mainly used when other software applications require its use.