# Server Socket

> Symcon documentation · English · generated on 2026-09-26  
> Index: https://www.symcon.de/en/llms.txt

Source: https://www.symcon.de/en/service/documentation/module-reference/i-o-instances/serversocket/

_Requires Symcon >= 4.1_

The server socket opens a port for all networks on the server. The port can then be listened on and data can be received on it.

Only a click on "Apply" saves the settings and then the port is opened.

If SSL is activated, the certificate and the private key must be specified.

![Configuration page](https://www.symcon.de/media/pages/service/dokumentation/modulreferenz/io/serversocket/21976726c8-1790424939/io-serversocket.png)

#### Create certificate
Using OpenSSL, certificates and private keys can be created.

```php
// Generate a private key
openssl genrsa -out pk.pem 1024

// Create a certificate signing request
openssl req -new -key pk.pem -out req.csr

// Self-sign the csr
openssl x509 -req -days 3650 -in req.csr -signkey pk.pem -out cert.pem
```

> **Note:** The certificate for the certification authority is optional.

## SSCK_SendPacket

Source: https://www.symcon.de/en/service/documentation/module-reference/i-o-instances/serversocket/ssck-sendpacket/

`bool SSCK_SendPacket(int $InstanceID, string $Text, string $ClientIP, int $ClientPort)`

_Requires Symcon >= 4.1_

sends a string to the I/O

**Parameters**

- `$InstanceID` (int): ID of the server socket to be updated
- `$Text` (string): The string to be sent
- `$ClientIP` (string): Recipient's IP
- `$ClientPort` (int): Recipient's port

**Returns** (bool): If the command succeeds, it returns __TRUE__, otherwise __FALSE__.

Recipient's port

**Example**

```php
//Sends the packet with the data record "Any data record" on the server socket with ID 12345 to the IP:Port 192.168.1.123:1234
SSCK_SendPacket(12345, "Any data record", "192.168.1.123", 1234);
```

## SSCK_SendText

Source: https://www.symcon.de/en/service/documentation/module-reference/i-o-instances/serversocket/ssck-sendtext/

`bool SSCK_SendText(int $InstanceID, string $Text)`

_Requires Symcon >= 4.1_

sends a string to the I/O

**Parameters**

- `$InstanceID` (int): ID of the server socket to be updated
- `$Text` (string): The string to be sent

**Returns** (bool): If the command succeeds, it returns __TRUE__, otherwise __FALSE__.

The string to be sent

**Example**

```php
SSCK_SendText(12345, "Any data record"); //Sends the text "Any data record" to the server socket with the ID 12345
```