# Integration via SIP for Telephony Agents

SIP Guide: [<mark style="color:purple;">https://developer.nexmo.com/voice/sip/overview</mark>](https://developer.nexmo.com/voice/sip/overview)

Invite requests using your own Nexmo credentials with the following syntax:- \<AGENT\_PHONE\_NUMBER>@sip.nexmo.com

#### The following headers are accepted:

X-Vgai-Session-ID (optional): allows starting a conversation using a preconfigured session.