# Modbus TCP Server

Modbus TCP Server is a protocol used by the Master/Client that responds to queries received by the device. The ability to use this protocol in the inSCADA side provides a great deal of flexibility. inSCADA now gets a similar role as devices with the help of the protocol.

![Figure 1 : Modbus TCP Server ](/files/-LknGY7ugXVikboYOCVS)

As shown in Figure 1, inSCADA can now share data with other devices on the network using this protocol.

{% hint style="info" %}
Let's remember the Value Expression property of inSCADA. With the Modbus TCP Server protocol, you can make a simulator of any device in inSCADA using the value expression.
{% endhint %}

{% hint style="info" %}
You do not need to create virtual/internal variables in the inSCADA platform as you would do in any other SCADA software. If this is the case, you simply need to create a device using Modbus TCP Server protocol. It also has a much more powerful structure to hold data in memory in the inSCADA platform. See [getGlobalObject ](https://inscada.gitbook.io/ins/v/en-1/programing/apis/getglobalobject)and [setGlobalObject](https://inscada.gitbook.io/ins/v/en-1/programing/apis/setglobalobject).
{% endhint %}


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