SANKET vs Threema: a Threema alternative for sovereign organisations
Threema and SANKET share strengths: no phone number needed, and on-premise and air-gapped deployment. SANKET adds post-quantum PQXDH and SPQR in the current release, sign-in through the organisation's own directory, signed device lists, device mutual TLS and encrypted priority broadcast, from an Indian vendor.
About Threema
Threema GmbH · Switzerland
Threema is a Swiss secure messenger for individuals (Threema), organisations (Threema Work) and self-hosted deployments (Threema OnPrem). It end-to-end encrypts messages, media and calls as well as group names and member lists, uses the Ibex protocol, and needs no phone number to sign up. It announced hybrid post-quantum work with IBM Research in February 2026.
SANKET vs Threema: side by side
| Criterion | SANKET | Threema |
|---|---|---|
| Who controls the infrastructure | The customer. One dedicated installation per organisation, on infrastructure it owns or chooses, with no vendor-operated service in the message path. | Threema servers in Zurich, or the customer's own servers with Threema OnPrem. |
| Deployment options | Dedicated installation on any cloud in any region the customer chooses (or Tosh Defence hosting), customer on-premise, or fully air-gapped; single host or high availability with second-site recovery. | Hosted service, or Threema OnPrem self-hosted, including fully isolated air-gapped environments. |
| Who holds keys and identity | The customer and its users. Keys are generated on each device and protected by hardware-backed storage; identities are customer-controlled Sanket IDs, with no consumer phone-number identity required. | A random Threema ID, with no phone number required; linking a phone number or email is optional. |
| Encryption protocol | Signal Protocol through Signal's official, independently audited libsignal. Messages AES-256-CBC with HMAC-SHA256 inside libsignal; files and calls AES-256-GCM; TLS with AES-256-GCM suites only. | Ibex (since 2023). |
| Post-quantum protection | Yes, in the current release: PQXDH with a mandatory post-quantum Kyber prekey and the SPQR ratchet (Triple Ratchet), plus hybrid X25519MLKEM768 key exchange at the TLS edge. | Hybrid ML-KEM planned with IBM Research (announced February 2026). |
| Groups and calls end-to-end encrypted by default | Yes. One-to-one and group messages, reactions, encrypted broadcasts and files are always end-to-end encrypted; voice and video calls use AES-256-GCM frame encryption with five new frame keys per second, inside SRTP AES-256-GCM. | Yes: text and voice messages, media and calls end-to-end encrypted, as well as group names and member lists. |
| Customer identity provider (SSO / LDAP) | Yes. Sign-in through the customer's own OIDC, SAML 2.0 or LDAP directory, SCIM 2.0 provisioning, and FIDO2 security keys for administrators. | Not publicly documented |
| Admin controls and device governance | Device approval and revocation, lost mode and remote wipe, signed device lists, device mutual TLS, retention, forwarding and clipboard policy, customer-defined classification labels and a hash-chained audit log for the customer's SIEM. | OnPrem admin portal, MDM support, and whitelabel app name, icon and colours. |
| Data sovereignty (jurisdiction, built in India) | Built in India by Tosh Defence. Data stays in the jurisdiction and on the infrastructure the customer chooses, with no third-party analytics and no foreign runtime dependency in the products. | Threema GmbH, Switzerland; servers in Zurich. |
| Release integrity and update control | Ed25519-signed releases verified before install, with release freeze and rollback protection and automatic rollback on a failed upgrade. The customer decides when to upgrade, online or with a signed offline package. | Not publicly documented |
| Platforms | Native apps for iOS, Android, Windows, macOS and Linux. Browser-free by design: there is no web client to attack. | iOS, Android, desktop and web. |
Who controls the infrastructure
SANKET
The customer. One dedicated installation per organisation, on infrastructure it owns or chooses, with no vendor-operated service in the message path.
Threema
Threema servers in Zurich, or the customer's own servers with Threema OnPrem.Deployment options
SANKET
Dedicated installation on any cloud in any region the customer chooses (or Tosh Defence hosting), customer on-premise, or fully air-gapped; single host or high availability with second-site recovery.
Threema
Hosted service, or Threema OnPrem self-hosted, including fully isolated air-gapped environments.Who holds keys and identity
SANKET
The customer and its users. Keys are generated on each device and protected by hardware-backed storage; identities are customer-controlled Sanket IDs, with no consumer phone-number identity required.
Threema
A random Threema ID, with no phone number required; linking a phone number or email is optional.Encryption protocol
SANKET
Signal Protocol through Signal's official, independently audited libsignal. Messages AES-256-CBC with HMAC-SHA256 inside libsignal; files and calls AES-256-GCM; TLS with AES-256-GCM suites only.
Threema
Ibex (since 2023).Post-quantum protection
SANKET
Yes, in the current release: PQXDH with a mandatory post-quantum Kyber prekey and the SPQR ratchet (Triple Ratchet), plus hybrid X25519MLKEM768 key exchange at the TLS edge.
Threema
Hybrid ML-KEM planned with IBM Research (announced February 2026).Groups and calls end-to-end encrypted by default
SANKET
Yes. One-to-one and group messages, reactions, encrypted broadcasts and files are always end-to-end encrypted; voice and video calls use AES-256-GCM frame encryption with five new frame keys per second, inside SRTP AES-256-GCM.
Threema
Yes: text and voice messages, media and calls end-to-end encrypted, as well as group names and member lists.Customer identity provider (SSO / LDAP)
SANKET
Yes. Sign-in through the customer's own OIDC, SAML 2.0 or LDAP directory, SCIM 2.0 provisioning, and FIDO2 security keys for administrators.
Threema
Not publicly documentedAdmin controls and device governance
SANKET
Device approval and revocation, lost mode and remote wipe, signed device lists, device mutual TLS, retention, forwarding and clipboard policy, customer-defined classification labels and a hash-chained audit log for the customer's SIEM.
Threema
OnPrem admin portal, MDM support, and whitelabel app name, icon and colours.Data sovereignty (jurisdiction, built in India)
SANKET
Built in India by Tosh Defence. Data stays in the jurisdiction and on the infrastructure the customer chooses, with no third-party analytics and no foreign runtime dependency in the products.
Threema
Threema GmbH, Switzerland; servers in Zurich.Release integrity and update control
SANKET
Ed25519-signed releases verified before install, with release freeze and rollback protection and automatic rollback on a failed upgrade. The customer decides when to upgrade, online or with a signed offline package.
Threema
Not publicly documentedPlatforms
SANKET
Native apps for iOS, Android, Windows, macOS and Linux. Browser-free by design: there is no web client to attack.
Threema
iOS, Android, desktop and web.Where SANKET leads
- Post-quantum messaging in the current release: PQXDH with a mandatory Kyber prekey and the SPQR ratchet.
- Customer identity integration: SCIM, OIDC, SAML, LDAP and FIDO2 security keys for administrators.
- Signed device lists and device mutual TLS for every approved device.
- Encrypted priority broadcast with acknowledgement, and customer-defined classification labels inside the encryption.
- An Indian vendor and an Indian jurisdiction option for Indian government and defence buyers.
Frequently asked questions
What is a good Threema alternative for organisations?
SANKET (Sanket.Chat) by Tosh Defence. Like Threema it needs no phone number and deploys on-premise or air-gapped, and it adds post-quantum PQXDH and SPQR, the organisation's own identity provider and signed device lists.
Does SANKET need a phone number?
No consumer phone-number identity is required. Users are identified by Sanket ID, and a deployment without an SMS provider does not collect phone numbers.
Is SANKET's messaging post-quantum today?
Yes. Every session uses PQXDH with a mandatory post-quantum Kyber prekey and the SPQR ratchet alongside the Double Ratchet, through Signal's official libsignal.
Sources
- SANKET Technical Security & Architecture Whitepaper, public edition 2.0 (7 October 2026)
- Threema: Security
- Threema OnPrem
- Threema blog: A quantum-secure future (24 February 2026)
- Threema Private
- Threema blog: Anonymity
Sources checked on 7 October 2026. Competitor facts are taken only from the sources listed. Where no public source was found, the cell reads 'Not publicly documented'. Product and company names are trademarks of their respective owners.
Put your communications under your own control
Talk to the Tosh Defence team about your deployment, from a dedicated cloud installation to a fully air-gapped estate, or read the full security architecture first.