# How do I set up SIP signaling via TCP?

#### **SIP signaling via TCP**

**Transmission Control Protocol (TCP)** is a transport protocol used for reliable, connection-oriented, packet-switched transmission of data over the Internet. Currently, the connection via TCP/TLS is available with both IPv4 and IPv6.

The **User Datagram Protocol (UDP)** is also a transport protocol, but it does not transmit data in a connection-oriented way. Unlike TCP, when data is transmitted with UDP **no verification** of the data transmission takes place. This allows data to be transmitted faster, but the sender cannot determine whether the message arrived completely and at the correct recipient.

For real-time applications such as telephony, transmission with UDP is recommended because of the shorter transmission time, but using TCP can in some cases be advantageous or even necessary. On phones and routers, UDP is usually preset.

The **Setting up TCP** can be done in your phone, router, or VoIP app as follows:

➔ Enter as registrar/domain **sipgate.de** .

➔ In the Proxy/Outbound Proxy field, enter **sip.sipgate.de** .

➔ On some models, you must **signaling** change from UDP to TCP.

{% hint style="info" %}
**Tip:** If you do not see a field in the settings for changing the transport protocol, you can enter as Outbound Proxy **sip.sipgate.de;transport=tcp** .
{% endhint %}

#### **Configuration examples**

#### **Fritz!Box**

In the menu **Telephony ➔ Own phone numbers** open and edit the sipgate phone number:

**➔** Telephony provider: Other provider

**➔** Registrar: sipgate.de

**➔** Proxy server: sip.sipgate.de

**➔** STUN server: leave field blank

**➔** Additional connection settings ➔ Transport protocol: TCP

#### **Snom**

In the phone's web menu, select the corresponding **identity** and edit it:

**➔** Registrar: sipgate.de

**➔** Outbound proxy: sip.sipgate.de;transport=tcp

**Warning**: To save the settings, Plug & Play must first be deactivated.

#### **Gigaset**

In the web menu **Settings ➔ Telephony ➔ Connections** open and edit the sipgate connection:

**➔** Outbound proxy mode: always

**➔** Outbound server address: sip.sipgate.de

**➔** Outbound proxy port: 5060

**➔** Select network protocol: TCP only

#### **Yealink**

In the web menu under **Account** select the corresponding account and edit it as follows:

**➔** Enable outgoing proxy server: enabled

**➔** Outgoing proxy server 1: sip.sipgate.de (Port: 5060)

**➔** NAT: disabled

**➔** For SIP server 1, set the transport to TCP

#### **Grandstream**

In the web menu under **accounts** select the corresponding account and edit it as follows:

**➔** General settings ➔ Outbound Proxy: sip.sipgate.de

**➔** SIP settings ➔ Basic settings ➔ SIP Transport: TCP


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://help.sipgate.de/cloud-telefonanlage/en/using-sipgate/telefonie/wie-richte-ich-die-sip-signalisierung-via-tcp-ein.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.