# TLS
> Transport Layer Security – encrypts SIP signaling to protect call setup information

TLS encrypts SIP signaling, protecting call metadata and credentials from interception.

## What is TLS?
Transport Layer Security (TLS) is a cryptographic protocol that encrypts data in transit. In VoIP, TLS is applied to [SIP](/voip-glossary/sip/) signaling to protect call setup data — including caller/callee identities, credentials, and routing information — from eavesdropping and tampering.

## TLS and SRTP together
TLS secures the signaling plane while [SRTP](/voip-glossary/srtp/) secures the media plane. Enabling both ensures that neither call metadata nor voice/video content can be intercepted. Most [softphone](/voip-glossary/softphone/) apps, including those built on [Acrobits Cloud Softphone](/cloud-softphone/), support TLS out of the box.

## Related Terms
- [SRTP](/voip-glossary/srtp/)
- [SIP](/voip-glossary/sip/)