Configuring STIR/SHAKEN Trunk Settings for FCC RCMD Compliance in Genesys Cloud CX

How-To-Articles
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Configuring STIR/SHAKEN Trunk Settings for FCC RCMD Compliance in Genesys Cloud CX

What This Guide Covers

This guide details the configuration of Session Initiation Protocol (SIP) Trunks within Genesys Cloud CX to align with Federal Communications Commission (FCC) Robocall Mitigation Database (RCMD) registration requirements. Upon completion, you will have enabled STIR/SHAKEN signaling on outbound trunks with verified attestation levels, ensuring calls are authenticated by downstream carriers and reducing the risk of traffic blocking or labeling as spam.

Prerequisites, Roles & Licensing

Before implementing this configuration, verify that the following prerequisites are met to avoid service disruption during production deployment:

  • Licensing Tier: Enterprise Edition (CC CX Enterprise) is required for full STIR/SHAKEN visibility and control. Standard or Professional tiers may not expose specific attestation level controls via API.
  • Permissions: The user account executing these changes must possess the following granular permissions in Genesys Cloud:
    • Telephony > Trunk > Edit
    • Telephony > View Reports (for validation)
    • Admin > Users > Edit (to verify service users have correct scopes)
  • FCC RCMD Registration: The organization must have already completed the registration process at the FCC Robocall Mitigation Database portal (fcc.gov/rcmd). You will require the Organization ID or Registration Reference Number associated with this submission. Genesys Cloud does not register you on your behalf; it acts as the signaling endpoint.
  • Carrier Support: The upstream SIP Trunk provider must support STIR/SHAKEN protocols and be willing to accept attestation tokens from Genesys Cloud. Most major US carriers (AT&T, Verizon, T-Mobile) now require this for inbound and outbound routing.
  • OAuth Scopes: If automating via API, the access token requires conversation:telephony:trunks:read and conversation:telephony:trunks:write scopes.

The Implementation Deep-Dive

1. Understanding the Compliance Architecture

The FCC RCMD requirement mandates that all voice service providers register with the database to prove they are not malicious actors. However, registration alone does not prevent blocking. The technical implementation relies on STIR/SHAKEN protocols to attach cryptographic signatures to SIP INVITE requests. These signatures indicate the caller ID verification status (Attestation Level).

We configure Genesys Cloud CX to generate these tokens based on the customer relationship. If a call originates from an internal agent, we typically aim for ‘Full’ attestation (‘A’). If it originates from a third-party partner, we may use ‘Partial’ (‘B’). ‘Gateway’ (‘C’) is reserved for legacy gateways and often results in carrier filtering.

The Trap: Many architects enable STIR/SHAKEN on the trunk immediately without verifying the FCC RCMD registration status with their carrier. If you enable the feature in Genesys Cloud but your carrier has not received proof of your FCC registration, the carrier will reject the authentication headers or downgrade the attestation to ‘C’. This results in immediate call blocking by downstream endpoints like mobile devices that enforce strict spam filters. Always confirm with your Carrier Account Manager that they have updated their backend systems to recognize your Organization ID before modifying trunk settings.

2. Configuring SIP Trunk Attestation Levels

The core of this implementation involves updating the SIP Trunk configuration in Genesys Cloud CX to enable STIR/SHAKEN and define the default attestation level. This is done via the Admin UI or the REST API. The API approach allows for programmatic auditing and enforcement across multiple regions.

Use the PATCH endpoint to modify trunk properties. Ensure that the stirShakenEnabled field is set to true. Simultaneously, define the attestationLevel based on your compliance policy. For outbound dialing campaigns where caller ID is verified, use ‘FULL’.

API Endpoint:
PATCH /api/v2/conversations/telephony/trunks/{trunkId}

JSON Payload Example:

{
  "stirShakenEnabled": true,
  "attestationLevel": "FULL",
  "outboundCallerId": "+15550198765",
  "carrierName": "Genesys Cloud Telecom",
  "name": "Primary-Outbound-SIP-Trunk-RCMD"
}

Architectural Reasoning: We use the PATCH method rather than PUT because we are modifying specific fields without overwriting unrelated configuration such as encryption settings or QoS parameters. Setting attestationLevel to FULL signals to downstream networks that the calling party identity is fully verified against the subscriber database. This maximizes deliverability rates on mobile devices, which often suppress calls with ‘C’ attestation.

The Trap: A common error occurs when administrators set the outboundCallerId incorrectly while enabling STIR/SHAKEN. If the caller ID number does not match the registered numbers in the FCC RCMD database for your organization, the carrier will fail the signature check during validation. This results in a SIP 403 Forbidden response or immediate dropping of the call before it connects to the destination. Always cross-reference the outboundCallerId against your FCC Registration submission list to ensure exact string matching.

3. Verifying Attestation via Call Detail Records (CDRs)

Enabling the setting is only half the battle. You must validate that the signaling tokens are being generated and transmitted correctly during live traffic. Genesys Cloud CX includes STIR/SHAKEN specific fields in the Call Detail Records (CDRs). These records provide evidence of compliance for auditors.

Query the CDRs using the GET /api/v2/analytics/telephony/calls endpoint or export via Data Export API to a storage bucket for analysis. Look for the stirShakenStatus and attestationLevel fields in the returned JSON objects.

API Endpoint:
GET /api/v2/analytics/telephony/calls?startTime={ISO8601_START}&endTime={ISO8601_END}

JSON Response Snippet (Example):

{
  "data": [
    {
      "id": "call-uuid-12345",
      "stirShakenStatus": "SUCCESS",
      "attestationLevel": "FULL",
      "callerId": "+15550198765",
      "status": "COMPLETED"
    }
  ]
}

Architectural Reasoning: We rely on CDRs because they represent the ground truth of what was transmitted over the wire. A successful SUCCESS status indicates that the upstream carrier accepted the attestation token and forwarded it downstream. If you see a FAILED or UNKNOWN status, it implies a breakdown in the STIR/SHAKEN handshake between Genesys Cloud and your SIP Trunk provider.

The Trap: Do not rely solely on the UI status indicator for trunk health. The UI may show the configuration as active while the carrier backend has not yet propagated the policy update. Always correlate API responses with CDR data from a period of at least 24 hours after deployment to confirm end-to-end signaling success rates exceed 98%.

Validation, Edge Cases & Troubleshooting

Edge Case 1: Hybrid Deployment with On-Premise SIP Gateways

In hybrid environments where Genesys Cloud CX connects to on-premise PBX systems via Media Gateway, STIR/SHAKEN validation can fail at the gateway boundary. The gateway may terminate the encrypted token and re-instantiate a new call leg without preserving the attestation header.

  • The Failure Condition: Calls originating from the on-premises PBX show attestationLevel: UNKNOWN or FAILED in CDRs, even though the Genesys Cloud trunk is configured correctly.
  • The Root Cause: The media gateway does not support passing through SIP headers associated with STIR/SHAKEN (specifically the Identity header). It treats the call as a new originating point without cryptographic proof of identity.
  • The Solution: Configure the Media Gateway to preserve SIP headers during the signaling handoff. If the gateway hardware cannot support this, route all outbound traffic for RCMD compliance through Genesys Cloud native SIP Trunks rather than the on-premises extension. This ensures the STIR/SHAKEN signature is generated at the cloud layer where compliance controls are managed.

Edge Case 2: Carrier-Specific Attestation Requirements

Different carriers enforce different rules regarding attestation levels. For example, some mobile operators may reject ‘FULL’ attestation if the originating IP address does not match their whitelist for that specific carrier ID.

  • The Failure Condition: Calls successfully connect but are labeled as “Spam Likely” or blocked by the recipient device despite having SUCCESS status in CDRs.
  • The Root Cause: The carrier has updated its spam filtering algorithms to require a stricter mapping between the calling number and the originating IP address (IP reputation). This is often independent of STIR/SHAKEN but related to FCC RCMD compliance trends.
  • The Solution: Implement an IP Allowlist strategy with your SIP Trunk provider. Ensure that the IP addresses from which Genesys Cloud sends SIP traffic are whitelisted for each specific carrier you route through. Additionally, verify that the outboundCallerId matches the number registered in the FCC RCMD database exactly, including country codes and formatting.

Edge Case 3: API Rate Limiting During Bulk Configuration

When rolling out this configuration across hundreds of trunks or regions, automated scripts may hit rate limits on the Genesys Cloud API. This can leave some trunks in a partially configured state where STIR/SHAKEN is enabled but attestation levels are unset.

  • The Failure Condition: A subset of trunks shows stirShakenEnabled: true but lacks an attestationLevel, causing the platform to default to ‘GATEWAY’ (C) behavior for those calls.
  • The Root Cause: Exceeding the API rate limit (429 Too Many Requests) during a bulk PATCH operation without exponential backoff logic.
  • The Solution: Implement a retry mechanism with exponential backoff in your deployment script. Do not proceed to validation until all trunk updates return a 200 OK status. Use the GET /api/v2/conversations/telephony/trunks/{trunkId} endpoint to verify the final state of each trunk before considering the deployment complete.

Official References