# Strategic Mobile Developer Hub

Documentation for sending and receiving messages over a single REST API, and for
connecting to the platform over carrier-grade interconnect protocols.

## Communication channels

The REST API for messaging. SMS is available today. MMS support is available by
account configuration, and full MMS API documentation is coming soon.

[Browse channels →](/docs/api/channels)

## Protocols

Carrier-grade interconnect protocols for high-volume traffic: SMPP, MM4, and
MM7.

[View protocols →](/docs/protocols)

## Developer resources

Reference material that applies across the API.

- [Authentication](/docs/api/authentication) — Bearer token usage.
- [Rate limits](/docs/api/rate-limits) — throttling and `429` behavior.
- [Error codes](/docs/api/error-codes) — HTTP status code reference.


## Support

Need help? Visit [support.smscpr.com](https://support.smscpr.com).