> For the complete documentation index, see [llms.txt](https://docs.messageflow.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.messageflow.com/trust-center/communication-channel-security/sms-communication-security.md).

# SMS Communication Security

The security of your SMS communication is paramount. We ensure it through a combination of direct, high-quality connections, sender ID verification, and advanced, real-time threat protection.

* **Direct-to-Operator Connections:** Our priority is to ensure the highest quality and security of traffic. That is why **in Poland, we use only direct, certified connections to GSM operators**. This approach eliminates intermediaries and allows us to avoid "grey routing"—unofficial sending paths that can degrade deliverability and security. For international communication, we work with a global network of carefully selected, trusted partners to guarantee reliable and secure delivery of your messages worldwide.
* **Sender ID Management & Verification**: A recognizable Sender ID (the name that appears as the message sender) is crucial for recipient trust and brand protection. To prevent impersonation, we have a clear verification process for custom alphanumeric Sender IDs. Key practices include:
  * **Authorization Requirement:** Using a custom name (e.g., your company name) requires verification by our Customer Support team. After adding a name, you will receive an email confirming that it is awaiting approval. This process takes up to one business day.
  * **Character Limits:** The Sender ID must meet the following requirements: up to 11 characters for names containing text, digits, and/or spaces, or up to 14 characters for numeric-only names.
  * **Prohibited Names:** Using misleading names (e.g., "POLICE") is strictly forbidden to protect recipients.
  * **Two-Way Communication:** If you need to receive replies, consider using a dedicated 2-way number, as alphanumeric Sender IDs do not support incoming messages. \
    [Learn more about configuring Sender IDs](/sms/sms-common-settings/sender-ids.md)
* **Shield 360 Anti-Phishing Protection**: All SMS traffic is protected by our proprietary Shield 360 technology. It actively monitors for and blocks smishing attempts, malicious links, and impersonation of your brand in real-time.