VOS3000 Call Forward Signal Recognition Smart SS_RECOGNIZE_CALL_FORWARD_SIGNAL
Enabling VOS3000 call forward signal recognition with SS_RECOGNIZE_CALL_FORWARD_SIGNAL allows the softswitch to detect when calls are being forwarded by the upstream carrier or terminating gateway. When a SIP 181 Call Is Being Forwarded or SIP 302 Moved Temporarily response is received during call setup, VOS3000 can identify and flag the forwarding event in the CDR, enabling accurate billing for forwarded calls and proper routing decisions. Without this feature enabled, forwarded calls are processed identically to direct calls, leading to billing inaccuracies and missed routing intelligence. Need help with this? Contact us on WhatsApp: +8801911119966.
Call forwarding in VoIP networks is signaled through specific SIP response codes and headers. The SIP 181 Call Is Being Forwarded provisional response indicates that the call has been redirected to another destination. The SIP 302 Moved Temporarily response tells VOS3000 that the called number has been temporarily redirected and provides the new Contact URI. By recognizing these signals, VOS3000 can apply different billing rules, record the forwarding event in CDRs, and make informed routing decisions about whether to follow the redirect or stop the call attempt.
Table of Contents
SS_RECOGNIZE_CALL_FORWARD_SIGNAL Parameter Overview
The SS_RECOGNIZE_CALL_FORWARD_SIGNAL parameter is configured per mapping gateway under §2.5.1.2 of the VOS3000 administration manual. When enabled, VOS3000 actively monitors SIP responses for forwarding indicators and processes them accordingly.
| Parameter | Description | Values |
|---|---|---|
| SS_RECOGNIZE_CALL_FORWARD_SIGNAL | Enables/disables call forward signal recognition | Yes / No |
| Configuration Level | Per mapping gateway | Gateway-specific |
| Manual Section | VOS3000 mapping gateway reference | §2.5.1.2 |
| Affected SIP Responses | 181 Call Is Being Forwarded, 302 Moved Temporarily | SIP 1xx and 3xx classes |
SIP Forwarding Signals That VOS3000 Recognizes
VOS3000 call forward signal recognition monitors two primary SIP signaling events that indicate call forwarding. Understanding each signal helps operators configure the appropriate response for their deployment.
| SIP Signal | Code | Meaning | Contains New Destination? |
|---|---|---|---|
| Call Is Being Forwarded | 181 | Provisional — call is being redirected | May include new Contact |
| Moved Temporarily | 302 | Redirect — try the Contact URI | Yes — Contact header required |
Why Call Forward Signal Recognition Matters for Billing
When calls are forwarded, the actual destination may be in a different rate center or even a different country than the originally dialed number. Without VOS3000 call forward signal recognition, the system bills the call based on the original dialed number, which may result in undercharging for calls forwarded to more expensive destinations. Enabling this feature allows VOS3000 to flag forwarded calls in CDRs, enabling operators to apply different billing rules or investigate forwarding patterns. For billing configuration, see our VOS3000 billing system guide.
| Billing Aspect | Without Recognition | With Recognition |
|---|---|---|
| Rate basis | Original dialed number only | Can detect and flag forwarded calls |
| CDR recording | No forwarding indicator | CDR flagged with forwarding event |
| Revenue accuracy | May undercharge for expensive forwarded destinations | Can apply correct rates based on forwarding detection |
| Fraud detection | Cannot identify suspicious forwarding patterns | Forwarding events visible in CDR analysis |
Configuration Steps
Follow these steps to enable VOS3000 call forward signal recognition on a mapping gateway. For gateway configuration help, see our gateway configuration guide. For direct assistance, message us on WhatsApp: +8801911119966.
| Step | Action | Detail |
|---|---|---|
| 1 | Open mapping gateway | Gateway > Mapping Gateway in VOS3000 client |
| 2 | Locate forwarding setting | Find “Recognize Call Forward Signal” option |
| 3 | Enable recognition | Set to Yes |
| 4 | Save and apply | Click Save to apply gateway configuration |
| 5 | Test with forwarded call | Place a call to a forwarded number and check CDR for forwarding flag |
How VOS3000 Handles 302 Redirect Responses
When VOS3000 call forward signal recognition is enabled and a SIP 302 Moved Temporarily response is received, VOS3000 can extract the new destination from the Contact header and either follow the redirect (re-INVITE to the new URI) or treat the call as a forwarding event and record it in the CDR. The handling depends on your configuration and the specific VOS3000 version. For routing-related configuration, see our VOS3000 call routing guide.
| 302 Response Handling | Behavior | Use Case |
|---|---|---|
| Follow redirect | VOS3000 sends new INVITE to Contact URI | When you want to complete the forwarded call |
| Record and stop | Record forwarding event in CDR, release call | When forwarded calls should not be completed |
| Record and continue | Flag CDR and proceed with original routing | When forwarding is informational only |
Related Resources – VOS3000 Call Forward
- VOS3000 Billing System Guide
- VOS3000 Gateway Configuration Routing Mapping
- VOS3000 Call Routing Guide
- RFC 3261 – SIP: Session Initiation Protocol
Frequently Asked Questions About VOS3000 Call Forward Signal Recognition
What does SS_RECOGNIZE_CALL_FORWARD_SIGNAL do?
SS_RECOGNIZE_CALL_FORWARD_SIGNAL is a VOS3000 mapping gateway parameter that enables detection of call forwarding events signaled through SIP 181 Call Is Being Forwarded and SIP 302 Moved Temporarily responses. When enabled, VOS3000 monitors these responses from the terminating gateway, identifies the forwarding event, and can flag the CDR record to indicate that the call was forwarded. This enables operators to apply different billing rules for forwarded calls and monitor forwarding patterns in their traffic.
What is the difference between SIP 181 and SIP 302 for forwarding?
SIP 181 Call Is Being Forwarded is a provisional (1xx) response that informs VOS3000 the call is being redirected — the call setup continues with the forwarded destination. SIP 302 Moved Temporarily is a redirect (3xx) response that tells VOS3000 to try a different URI provided in the Contact header. The key difference is that 181 is informational and the call continues, while 302 requires VOS3000 to decide whether to follow the redirect or terminate the call. Both indicate forwarding, but they require different handling logic.
Why should I enable call forward signal recognition?
You should enable VOS3000 call forward signal recognition to ensure accurate billing and CDR recording for forwarded calls. When calls are forwarded to different destinations, the actual termination cost may differ significantly from the originally dialed number’s rate. Without forwarding detection, these calls are billed at the original rate, causing revenue leakage. Additionally, recognizing forwarding events helps detect fraud patterns where malicious actors forward calls to premium-rate numbers, and it provides visibility into carrier forwarding behavior that may affect quality metrics.
Does enabling this feature affect call completion rates?
Enabling VOS3000 call forward signal recognition does not inherently affect call completion rates. The feature detects forwarding events and records them in CDRs — it does not block or modify calls. However, if your configuration includes actions to stop or redirect calls upon detecting forwarding, then those actions may affect completion rates. In most deployments, the recognition feature is purely informational and does not interfere with normal call processing.
Can VOS3000 automatically follow 302 redirects?
Yes, VOS3000 can be configured to automatically follow SIP 302 Moved Temporarily redirects by sending a new INVITE to the Contact URI provided in the 302 response. This behavior depends on your mapping gateway configuration and VOS3000 version. When VOS3000 follows a redirect, the resulting call is completed to the forwarded destination, and the CDR reflects the forwarding event. Operators should consider whether following redirects is appropriate for their business model, as forwarded calls may terminate at more expensive destinations.
How is call forwarding recorded in VOS3000 CDRs?
When VOS3000 call forward signal recognition is enabled and a forwarding event is detected, the CDR record includes indicators showing that the call was forwarded. The specific CDR fields may include a forwarding flag, the original dialed number, and potentially the forwarded-to number if available from the SIP signaling. These fields enable operators to filter and analyze forwarded calls in their CDR reporting systems. The exact CDR format depends on the VOS3000 version and billing configuration.
Professional VOS3000 Forwarding Configuration
Properly configuring VOS3000 call forward signal recognition ensures that forwarding events are detected, recorded, and handled correctly for billing and routing purposes. Our VOS3000 team can help you enable and optimize this feature across all your mapping gateways.
Contact us on WhatsApp: +8801911119966
From forwarding detection to billing optimization and fraud prevention, we provide expert VOS3000 support. Reach out today at +8801911119966 and take full control of forwarded call handling.
📞 Need Professional VOS3000 Setup Support?
For professional VOS3000 installations and deployment, VOS3000 Server Rental Solution:
📱 WhatsApp: +8801911119966
🌐 Website: www.vos3000.com
🌐 Blog: multahost.com/blog
📥 Downloads: VOS3000 Downloads
 | | |
