🔐 Have you ever needed to protect caller identity on your VOS3000 softswitch — but found yourself confused by the three different privacy modes and how they interact with per-gateway settings? The VOS3000 SIP privacy header is the key to controlling exactly how caller ID information is exposed or hidden in your SIP signaling. Configured via SS_SIP_USER_AGENT_PRIVACY, this parameter determines whether VOS3000 includes a Privacy header in outbound SIP messages and what value that header carries. 🛡️
📞 Whether you are managing wholesale VoIP routes that require caller ID hiding, enterprise PBX trunks with privacy requirements, or regulatory compliance for caller identification, understanding the VOS3000 SIP privacy header is essential. The global parameter controls the default behavior, while per-gateway settings on Routing Gateways and Mapping Gateways give you granular control over each interconnect. This guide covers every aspect — from the three global modes (Ignore/Id/None) to per-gateway Privacy, P-Asserted-Identity, and P-Preferred-Identity configuration. 🎯
🔧 We will reference only official VOS3000 2.1.9.07 manual data — no guesses, no fabricated values. Let’s dive in! 💡
🛡️ The VOS3000 SIP privacy header controls whether VOS3000 includes a Privacy header in SIP messages sent by registered user agents. The Privacy header, defined in RFC 3323, signals to downstream entities how the caller’s identity should be handled — specifically whether the caller ID should be hidden from the called party or displayed normally. 📞
📋 This parameter is governed by SS_SIP_USER_AGENT_PRIVACY with a default value of Ignore. Here is the official reference from the VOS3000 2.1.9.07 manual:
| Attribute | Value |
|---|---|
| 📌 Parameter Name | SS_SIP_USER_AGENT_PRIVACY |
| 🔢 Default Value | Ignore |
| 📝 Description | Privacy Setting for Register User |
| ⚙️ Options | Ignore / Id / None |
| 📍 Navigation | Operation management → Softswitch management → Additional settings → SIP parameter |
💡 Key insight: The default of “Ignore” means VOS3000 does NOT include any Privacy header in outbound SIP messages. This is the most common setting for standard VoIP deployments where caller ID presentation is the default behavior. Only when you change this to “Id” or “None” will VOS3000 actively insert a Privacy header.
⚠️ Without proper privacy header configuration, several problems can occur:
📊 The SS_SIP_USER_AGENT_PRIVACY parameter offers three distinct modes, each producing a different SIP signaling behavior. Understanding exactly what each mode does is critical for proper configuration. 🔑
| Mode | SIP Header Output | Meaning | Use Case |
|---|---|---|---|
| 🚫 Ignore (Default) | No Privacy field | VOS3000 does not add any Privacy header — caller ID is presented normally | Standard VoIP — caller ID shown to called party |
| 🔐 Id | Privacy: id | Requests identity privacy — the caller ID should be hidden from the called party but available to trusted network entities | Caller ID blocking — caller requested privacy |
| 🔓 None | Privacy: none | Explicitly states no privacy is requested — caller ID may be displayed | Explicit caller ID presentation — overrides network defaults |
🔑 Critical distinction: “Privacy: id” and “Privacy: none” are NOT the same as omitting the header entirely. According to RFC 3323, the absence of a Privacy header means no privacy preference is expressed (the network decides), while “Privacy: none” explicitly declares that no privacy is requested. “Privacy: id” requests that the calling user’s identity be kept private from the called party. 📡
📞 VOS3000 SIP Privacy Header — Message Examples: ───────────────────────────────────────────────── 🚫 Mode: Ignore (Default) — No Privacy header ───────────────────────────────────────────────── INVITE sip:bob@example.com SIP/2.0 Via: SIP/2.0/UDP 192.168.1.1:5060 From: "Alice" <sip:alice@example.com>;tag=1234 To: <sip:bob@example.com> Call-ID: abc123@example.com CSeq: 1 INVITE Content-Type: application/sdp Content-Length: ... ← No Privacy header present ───────────────────────────────────────────────── 🔐 Mode: Id — Privacy: id header added ───────────────────────────────────────────────── INVITE sip:bob@example.com SIP/2.0 Via: SIP/2.0/UDP 192.168.1.1:5060 From: "Anonymous" <sip:anonymous@example.com>;tag=1234 To: <sip:bob@example.com> Privacy: id Call-ID: abc123@example.com CSeq: 1 INVITE Content-Type: application/sdp Content-Length: ... ← Privacy: id — caller identity hidden ───────────────────────────────────────────────── 🔓 Mode: None — Privacy: none header added ───────────────────────────────────────────────── INVITE sip:bob@example.com SIP/2.0 Via: SIP/2.0/UDP 192.168.1.1:5060 From: "Alice" <sip:alice@example.com>;tag=1234 To: <sip:bob@example.com> Privacy: none Call-ID: abc123@example.com CSeq: 1 INVITE Content-Type: application/sdp Content-Length: ... ← Privacy: none — no privacy requested
🔧 While SS_SIP_USER_AGENT_PRIVACY controls the global default, VOS3000 provides powerful per-gateway privacy controls on Routing Gateways. These settings are found in Routing Gateway > Additional settings > Protocol > SIP and offer far more granularity than the global parameter alone. 🎯
💡 The per-gateway settings include not just the Privacy header, but also the P-Preferred-Identity and P-Asserted-Identity headers — both defined in RFC 3325. These identity headers work together with the Privacy header to provide a complete caller identification and privacy framework. 📋
| Setting | Options | Description |
|---|---|---|
| 🛡️ Privacy | None / Passthrough / Id | SIP Privacy header — controls caller ID privacy for this gateway |
| 👤 P-Preferred-Identity | None / Passthrough / Caller | SIP P-Preferred-Identity header — preferred identity for the caller |
| 📋 P-Asserted-Identity | None / Passthrough / Caller | SIP P-Asserted-Identity header — asserted identity for the caller |
| 📞 Caller dial plan | Dial plan selection | Dial plans for the caller number in “P-Asserted-Identity” field |
📊 The per-gateway Privacy setting on Routing Gateways provides three options that differ from the global SS_SIP_USER_AGENT_PRIVACY modes. Here is what each option does: 🔍
| Option | SIP Header Effect | Behavior | When to Use |
|---|---|---|---|
| 🚫 None | No Privacy field added | VOS3000 does not add any Privacy header to outbound INVITE messages via this gateway | Standard termination — caller ID presented normally |
| 🔄 Passthrough | Pass through privacy field | VOS3000 forwards any existing Privacy header from the incoming call leg to the outbound leg via this gateway | Transparent proxy — honor upstream privacy requests |
| 🔐 Id | Add Privacy: id header | VOS3000 actively adds “Privacy: id” to outbound INVITE messages via this gateway | Force caller ID hiding on this gateway |
💡 Important: The Passthrough option is particularly powerful for wholesale VoIP providers. When a downstream carrier sends a call with “Privacy: id” and you need to forward that call to a termination provider, Passthrough ensures the privacy request is honored end-to-end. Without Passthrough, the Privacy header would be dropped and the caller ID could be exposed. For more on SIP call flow, see our SIP call flow guide. 📡
👤 The P-Asserted-Identity (PAI) and P-Preferred-Identity (PPI) headers work hand-in-hand with the VOS3000 SIP privacy header. While the Privacy header controls whether the caller ID should be hidden, the PAI and PPI headers carry the actual caller identity information within the trusted network. 🔐
🎯 For a deep dive into PAI configuration, see our dedicated VOS3000 P-Asserted-Identity caller ID guide. Below is the per-gateway reference for both headers:
| Header | Option | SIP Effect | Use Case |
|---|---|---|---|
| 📋 P-Asserted-Identity | None | No PAI header added | Provider does not require PAI |
| 📋 P-Asserted-Identity | Passthrough | Forward existing PAI header from upstream | Transparent — forward caller identity |
| 📋 P-Asserted-Identity | Caller | Add PAI header with caller number | Provider requires PAI for caller identification |
| 👤 P-Preferred-Identity | None | No PPI header added | Standard — no PPI needed |
| 👤 P-Preferred-Identity | Passthrough | Forward existing PPI header from upstream | Transparent — forward preferred identity |
| 👤 P-Preferred-Identity | Caller | Add PPI header with caller number | UAC-originated calls with preferred identity |
🔐 Key relationship: When Privacy: id is set and P-Asserted-Identity is also configured, the PAI header carries the real caller identity within the trusted network while the Privacy header instructs the network to hide this identity from the called party. The From header is typically set to “Anonymous” while the PAI contains the actual number. This is the standard pattern for caller ID blocking in SIP networks per RFC 3325. 📡
🔧 The Caller dial plan setting in the Routing Gateway SIP configuration determines how the caller number is formatted in the P-Asserted-Identity field. This is essential when the termination provider requires a specific number format (e.g., E.164 with country code, or local format without country code). The dial plan transforms the caller number before it is placed in the PAI header. 📋
💡 For comprehensive caller ID management including dial plans and number formatting, refer to our VOS3000 caller ID management guide. 🎯
🖥️ In addition to Routing Gateway settings, VOS3000 also provides privacy control on the Mapping Gateway side. This is configured in Mapping Gateway > Additional settings > Protocol > SIP. 🔧
| Setting | Description |
|---|---|
| 🛡️ Support Privacy | Pass through mapping gateway private domain — forwards Privacy header through the mapping gateway |
💡 What this does: When Support Privacy is enabled on a Mapping Gateway, VOS3000 passes through the Privacy header from the originating side to the routing side through the mapping gateway’s private domain. This ensures that privacy requests are preserved across the mapping gateway boundary. If disabled, the Privacy header may be stripped when the call traverses the mapping gateway. 📡
🎯 When to enable: Enable Support Privacy on Mapping Gateways when you need end-to-end privacy header preservation across multiple network domains. This is critical for wholesale VoIP providers who need to honor upstream privacy requests when routing calls through mapping gateways. For more about gateway configuration, see our gateway configuration guide. 🔗
📊 The SS_SIP_E164_DISPLAY_FROM parameter is closely related to the VOS3000 SIP privacy header. While the Privacy header controls whether the caller ID is hidden, SS_SIP_E164_DISPLAY_FROM controls how the caller’s display information appears in the SIP From header. 📋
| Attribute | Value |
|---|---|
| 📌 Parameter Name | SS_SIP_E164_DISPLAY_FROM |
| 🔢 Default Value | Ignore |
| 📝 Description | Mode of SIP display information |
| 📍 Navigation | Operation management → Softswitch management → Additional settings → SIP parameter |
💡 Why it matters: When SS_SIP_USER_AGENT_PRIVACY is set to “Id” (Privacy: id), the From header display name is typically changed to “Anonymous.” The SS_SIP_E164_DISPLAY_FROM parameter controls the display information format in the From header independently — it determines whether the display portion uses E.164 format, the original format, or is ignored. Both parameters work together to control how caller identity is presented in SIP signaling. For the complete parameter reference, see our VOS3000 parameter description and system parameters guide. 🔧
⚙️ Follow these steps to configure the VOS3000 SIP privacy header on your system:
📝 After configuration, verify the privacy headers are working correctly using SIP debug tools. For comprehensive debugging instructions, see our VOS3000 troubleshooting guide.
📞 VOS3000 SIP Privacy Header — Verification Flow: Caller ──────────── VOS3000 ──────────── Termination Gateway │ │ │ │── INVITE ───────────►│ │ │ From: sip:1234@... │ │ │ Privacy: id │ │ │ │ │ │ │── INVITE ───────────────►│ │ │ From: Anonymous@... │ │ │ Privacy: id │ ← Per-gateway Privacy=Id │ │ P-Asserted-Identity: │ ← Per-gateway PAI=Caller │ │ <sip:1234@domain> │ │ │ │ │ │ ✅ Called party sees: │ │ │ "Anonymous" (From) │ │ │ Trusted network sees: │ │ │ 1234 (PAI header) │
🎯 Different VoIP deployment types require different privacy header configurations. Here are our recommended settings based on real-world experience: 💡
| Deployment Type | Global Privacy | Routing GW Privacy | PAI Setting | Rationale |
|---|---|---|---|---|
| 📞 Wholesale VoIP | Ignore | Passthrough | Caller | Honor upstream privacy; provide PAI for caller ID delivery |
| 🏢 Enterprise PBX | Ignore | None or Passthrough | Caller | Present caller ID normally; PAI for carrier requirements |
| 🔐 Privacy-required routes | Id | Id | Caller | Force Privacy: id on all calls; PAI carries real number in trusted network |
| 📡 SIP trunking | Ignore | Passthrough | Passthrough or Caller | Transparent privacy handling; follow upstream provider requirements |
| 🌍 Multi-carrier routing | Ignore | Per-carrier settings | Per-carrier settings | Different carriers have different PAI and privacy requirements |
💡 Pro tip: The most flexible approach is to set the global SS_SIP_USER_AGENT_PRIVACY to Ignore and then use per-gateway settings on Routing Gateways for specific privacy requirements. This way, each termination provider can have its own Privacy, PAI, and PPI settings without affecting other gateways. For call routing configuration, see our call routing guide. 📊
⚠️ Misconfigured privacy headers can cause a range of issues. Here are the most common problems and their solutions:
🔍 Symptom: SS_SIP_USER_AGENT_PRIVACY is set to “Id” but the called party still sees the caller number.
💡 Cause: The per-gateway Privacy setting on the Routing Gateway may be set to “None,” which overrides the global parameter. Or the termination provider is ignoring the Privacy header and reading the number from the PAI header without honoring the privacy indicator.
✅ Solutions:
🔍 Symptom: Privacy header is present on the originating side but missing on the termination side after the call passes through a Mapping Gateway.
💡 Cause: The Mapping Gateway’s Support Privacy setting is not enabled, so the Privacy header is stripped during the mapping gateway traversal.
✅ Solutions:
🔍 Symptom: Calls to a specific termination provider are rejected with SIP 403 or 403 errors. The provider requires a P-Asserted-Identity header.
💡 Cause: The P-Asserted-Identity setting on the Routing Gateway for this provider is set to “None,” so no PAI header is included in the outbound INVITE.
✅ Solutions:
🔍 Symptom: Privacy behavior is inconsistent — some gateways hide caller ID and others do not, and you are unsure which setting is in control.
💡 Cause: Both the global SS_SIP_USER_AGENT_PRIVACY and per-gateway Privacy settings exist, and they can conflict or produce unexpected results when not coordinated.
✅ Solutions:
📊 Here is the complete reference table for all privacy-related parameters and settings in VOS3000:
| Parameter / Setting | Default | Location | Scope |
|---|---|---|---|
| SS_SIP_USER_AGENT_PRIVACY | Ignore | SIP parameter (global) | All registered users |
| SS_SIP_E164_DISPLAY_FROM | Ignore | SIP parameter (global) | All SIP display information |
| Privacy (Routing GW) | — | Routing GW > SIP | Per-routing-gateway |
| P-Asserted-Identity (Routing GW) | — | Routing GW > SIP | Per-routing-gateway |
| P-Preferred-Identity (Routing GW) | — | Routing GW > SIP | Per-routing-gateway |
| Caller dial plan (Routing GW) | — | Routing GW > SIP | Per-routing-gateway (PAI format) |
| Support Privacy (Mapping GW) | — | Mapping GW > SIP | Per-mapping-gateway |
📍 Global SIP parameters are located at: Navigation → Operation management → Softswitch management → Additional settings → SIP parameter
✅ Use this checklist when deploying or tuning your VOS3000 SIP privacy header settings:
| Check | Action | Status |
|---|---|---|
| 📌 1 | Set SS_SIP_USER_AGENT_PRIVACY to appropriate mode (Ignore/Id/None) for your deployment | ☐ |
| 📌 2 | Configure per-gateway Privacy on each Routing Gateway (None/Passthrough/Id) | ☐ |
| 📌 3 | Set P-Asserted-Identity on each Routing Gateway per provider requirements | ☐ |
| 📌 4 | Configure P-Preferred-Identity where needed (typically for UAC-originated calls) | ☐ |
| 📌 5 | Select Caller dial plan for PAI number formatting on each Routing Gateway | ☐ |
| 📌 6 | Enable Support Privacy on Mapping Gateways that need to preserve privacy headers | ☐ |
| 📌 7 | Verify with SIP trace that Privacy and identity headers appear correctly in outbound INVITE | ☐ |
| 📌 8 | Review SS_SIP_E164_DISPLAY_FROM for consistent From header display behavior | ☐ |
🛡️ The default VOS3000 SIP privacy header setting is Ignore, configured via the SS_SIP_USER_AGENT_PRIVACY parameter. When set to Ignore, VOS3000 does not include any Privacy header in SIP messages — caller ID is presented normally. The other options are “Id” (adds Privacy: id to hide caller identity) and “None” (adds Privacy: none to explicitly indicate no privacy requested). 🔔
📊 Privacy: id requests that the calling user’s identity be kept private from the called party — the From header typically shows “Anonymous” while the real number is carried in the P-Asserted-Identity header within the trusted network. Privacy: none explicitly states that no privacy is requested and the caller ID may be displayed. The key difference from having no Privacy header at all is that “Privacy: none” is an explicit declaration, while the absence of a header means no privacy preference is expressed. Per RFC 3323, these are semantically different. 📡
🔧 The global SS_SIP_USER_AGENT_PRIVACY controls the default privacy behavior for all registered user agents. The per-gateway Privacy settings on Routing Gateways provide more granular control for each termination interconnect. The recommended approach is to set the global parameter to Ignore and use per-gateway settings for specific requirements — this gives you the most flexibility. Per-gateway settings take precedence over the global default for calls routed through that specific gateway. 🖥️
🔄 Use Passthrough when you need to preserve an existing Privacy header from an upstream provider. For example, if a wholesale customer sends a call with “Privacy: id” and you need to forward that call to a termination provider while honoring the privacy request, set the Routing Gateway’s Privacy to Passthrough. This is the most common setting for wholesale VoIP providers who act as a transit between originating and terminating networks. Without Passthrough, the Privacy header would be dropped and the caller ID could be exposed unintentionally. 📞
🔐 Yes, in most cases. When Privacy: id is set, the From header displays “Anonymous” to the called party. However, the real caller identity still needs to be communicated within the trusted network for billing, routing, and regulatory purposes. The P-Asserted-Identity (PAI) header carries this information — it is visible to trusted network entities but should not be forwarded to untrusted endpoints. Setting PAI to “Caller” on the Routing Gateway ensures the real number is included in the PAI header while the Privacy header keeps it hidden from the called party. For detailed PAI configuration, see our P-Asserted-Identity guide. 📋
🖥️ The Support Privacy setting on Mapping Gateways enables the pass-through of the Privacy header across the mapping gateway’s private domain. When enabled, any Privacy header present in the incoming call leg is preserved and forwarded to the outbound routing side. When disabled, the Privacy header may be stripped when the call traverses the mapping gateway boundary. Enable this setting when you need end-to-end privacy header preservation in multi-domain deployments — especially critical for wholesale VoIP providers. 🔄
🔍 Start by capturing a SIP trace on both the incoming and outgoing sides of VOS3000. Verify that the Privacy header appears (or does not appear) as expected in the outbound INVITE. Check that per-gateway Privacy settings match your expectations for each Routing Gateway. If privacy headers are missing after a Mapping Gateway, verify that Support Privacy is enabled. For PAI-related issues, confirm the P-Asserted-Identity setting is configured to “Caller” and the Caller dial plan is correct. For detailed troubleshooting, see our VOS3000 troubleshooting guide. For expert support, contact us on WhatsApp at +8801911119966. 📞
🔧 Configuring the VOS3000 SIP privacy header correctly is essential for protecting caller identity, meeting regulatory requirements, and maintaining compatibility with termination providers. Whether you need help with global parameter tuning, per-gateway Privacy and PAI configuration, or troubleshooting caller ID exposure issues, our team is ready to assist. 🛡️
💬 WhatsApp: +8801911119966 — Get instant support for VOS3000 SIP privacy header configuration, caller ID protection, and identity header setup. 🌐
📞 Still have questions about the VOS3000 SIP privacy header? Reach out on WhatsApp at +8801911119966 — we provide professional VOS3000 installation, configuration, and support services worldwide. For official VOS3000 software downloads, visit vos3000.com. 🌐
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