Using Zoom’s desktop and mobile clients, you can make secure voice calls on any SIP device. For calls and during phone provisioning sessions, Zoom Phone uses the advanced encryption standard Advanced Encryption Standard (AES) 256-bit algorithm using SIP over TLS 1.2. Zoom desktop and mobile clients, as well as devices, use SRTP with AES-256 bit encryption while Zoom devices use AES-128 or AES-256 bit encryption.
Devices are configured to use AES-128 bit encryption by default. AES-256 bit encryption needs to be upgraded via the web portal.
Zoom Phone desktop client and mobile app
Zoom Phone supports SIP signaling with AES-256 bit encryption between the client and server in versions 5.0.0 and higher. SRTP and AES-256 encryption protect media calls.
Zoom Phone devices
During phone provisioning sessions and for calls, Zoom Phone uses SIP over TLS 1.2 Advanced Encryption Standard (AES) 256-bit encryption. SRTP with AES-128 algorithm is also used to transport and protect call media. Users of Zoom Phone can upgrade to AES-256 bit encryption for supported devices. See the list of certified devices.
Upgrade to AES-256 bit encryption
It is possible for administrators to upgrade specific models within a website to be encrypted using AES-256 bits.
- Log into the Zoom web portal by using your Zoom username and password.
- Next, click Phone System Management, and then click Company Information in the navigation menu.
- Select the name of the site you want to edit from the list of sites if you have more than one.
- Choose the Site Settings option.
- Click the Add button under the Security section.
- Choose a model and a brand, then click Save.
- You can add more than one device at a time.
Downgrading to AES-128 bit encryption
You can downgrade to AES-128 bit encryption if you previously upgraded to AES-256 bit encryption.
- You will need to sign into the Zoom web portal in order to get started.
- Choose Phone System Management from the navigation menu.
- Select the site you want to edit if you have more than one.
- Choose Settings from the menu.
- You can downgrade a model to AES-128 bit encryption by clicking the icon in the Security section.