{"id":1300,"date":"2026-04-21T02:17:19","date_gmt":"2026-04-21T02:17:19","guid":{"rendered":"https:\/\/www.vos3000.com\/blog\/?p=1300"},"modified":"2026-04-21T02:17:29","modified_gmt":"2026-04-21T02:17:29","slug":"vos3000-sip-outbound-registration","status":"publish","type":"post","link":"https:\/\/www.vos3000.com\/blog\/vos3000-sip-outbound-registration\/","title":{"rendered":"VOS3000 SIP Outbound Registration Parameters: Expiry and Retry Delay Easy Guide"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\" id=\"vos-3000-sip-outbound-registration-parameters-expiry-and-retry-delay-guide\">VOS3000 SIP Outbound Registration Parameters: Expiry and Retry Delay Guide<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">\u23f1\ufe0f Two parameters control the entire lifecycle of VOS3000&#8217;s outbound SIP registration: <strong>SS_SIP_USER_AGENT_EXPIRE<\/strong> determines how long your registration stays valid, and <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong> determines how quickly VOS3000 recovers when registration fails. Together, these <strong>VOS3000 SIP outbound registration parameters<\/strong> govern whether your SIP trunks stay connected or silently go offline \u2014 and most operators never realize the connection until calls start failing. \ud83d\udcc9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd27 When VOS3000 registers outbound to another server (a wholesale carrier, upstream provider, or peer softswitch), the registration expiry controls how often VOS3000 must refresh its registration, while the retry delay controls recovery timing when things go wrong. Set the expiry too long behind NAT and your pinhole closes, killing inbound calls silently. Set the retry delay too low and you flood the upstream server with registration attempts. Set it too high and your trunk stays down for minutes when it could have recovered in seconds. \u2696\ufe0f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcde This guide covers both parameters in detail \u2014 from the Auto Negotiation behavior of SS_SIP_USER_AGENT_EXPIRE (default: Auto, range: 20\u20137200 seconds) to the failover timing of SS_SIP_USER_AGENT_RETRY_DELAY (default: 60 seconds, range: 30\u2013600 seconds) \u2014 plus the companion parameters for clean disconnection, privacy, and endpoint-side registration handling. All data is sourced exclusively from the official VOS3000 V2.1.9.07 Manual, Section 4.3.5.2 (Tables 4-3 and 4-4). For expert assistance, contact us on WhatsApp at <strong>+8801911119966<\/strong>. \ud83d\udca1<\/p>\n\n\n\n<div class=\"wp-block-rank-math-toc-block\" id=\"rank-math-toc\"><h2>Table of Contents<\/h2><nav><ul><li><a href=\"#vos-3000-sip-outbound-registration-parameters-expiry-and-retry-delay-guide\">VOS3000 SIP Outbound Registration Parameters: Expiry and Retry Delay Guide<\/a><ul><li><a href=\"#\ud83d\udd10-what-are-the-vos-3000-sip-outbound-registration-parameters\">\ud83d\udd10 What Are the VOS3000 SIP Outbound Registration Parameters?<\/a><\/li><li><a href=\"#\u23f1\ufe0f-ss-sip-user-agent-expire-registration-expiry\">\u23f1\ufe0f SS_SIP_USER_AGENT_EXPIRE \u2014 Registration Expiry<\/a><ul><li><a href=\"#\ud83d\udd04-auto-negotiation-vs-fixed-expiry-how-it-works\">\ud83d\udd04 Auto Negotiation vs. Fixed Expiry \u2014 How It Works<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udd04-ss-sip-user-agent-retry-delay-registration-failure-retry\">\ud83d\udd04 SS_SIP_USER_AGENT_RETRY_DELAY \u2014 Registration Failure Retry<\/a><ul><li><a href=\"#\ud83d\udd04-retry-delay-vs-registration-expiry-key-difference\">\ud83d\udd04 Retry Delay vs. Registration Expiry \u2014 Key Difference<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udccb-companion-user-agent-registration-parameters\">\ud83d\udccb Companion User Agent Registration Parameters<\/a><\/li><li><a href=\"#\ud83d\udce1-endpoint-registration-expiry-the-other-side-of-the-coin\">\ud83d\udce1 Endpoint Registration Expiry \u2014 The Other Side of the Coin<\/a><ul><li><a href=\"#\ud83d\udd10-system-level-endpoint-retry-parameters\">\ud83d\udd10 System-Level Endpoint Retry Parameters<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udd04-vos-3000-sip-outbound-registration-and-server-redundancy\">\ud83d\udd04 VOS3000 SIP Outbound Registration and Server Redundancy<\/a><ul><li><a href=\"#\ud83d\udce1-failover-timing-analysis\">\ud83d\udce1 Failover Timing Analysis<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udd27-step-by-step-vos-3000-sip-outbound-registration-configuration\">\ud83d\udd27 Step-by-Step VOS3000 SIP Outbound Registration Configuration<\/a><ul><li><a href=\"#step-1-configure-global-ss-sip-user-agent-expire-\ud83d\udccb\">Step 1: Configure Global SS_SIP_USER_AGENT_EXPIRE \ud83d\udccb<\/a><\/li><li><a href=\"#step-2-configure-ss-sip-user-agent-retry-delay-\ud83d\udd04\">Step 2: Configure SS_SIP_USER_AGENT_RETRY_DELAY \ud83d\udd04<\/a><\/li><li><a href=\"#step-3-configure-companion-parameters-\ud83d\udd17\">Step 3: Configure Companion Parameters \ud83d\udd17<\/a><\/li><li><a href=\"#step-4-configure-per-registration-settings-\ud83d\udda5\ufe0f\">Step 4: Configure Per-Registration Settings \ud83d\udda5\ufe0f<\/a><\/li><li><a href=\"#step-5-verify-registration-with-sip-debug-\ud83d\udd0d\">Step 5: Verify Registration with SIP Debug \ud83d\udd0d<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udcca-vos-3000-sip-outbound-registration-best-practices-by-scenario\">\ud83d\udcca VOS3000 SIP Outbound Registration Best Practices by Scenario<\/a><\/li><li><a href=\"#\ud83d\udee1\ufe0f-common-vos-3000-sip-outbound-registration-problems-and-solutions\">\ud83d\udee1\ufe0f Common VOS3000 SIP Outbound Registration Problems and Solutions<\/a><ul><li><a href=\"#\u274c-problem-1-trunk-works-then-silently-stops-receiving-calls\">\u274c Problem 1: Trunk Works Then Silently Stops Receiving Calls<\/a><\/li><li><a href=\"#\u274c-problem-2-excessive-register-messages-flooding-the-network\">\u274c Problem 2: Excessive REGISTER Messages Flooding the Network<\/a><\/li><li><a href=\"#\u274c-problem-3-registration-fails-and-never-recovers\">\u274c Problem 3: Registration Fails and Never Recovers<\/a><\/li><li><a href=\"#\u274c-problem-4-registration-flooding-upstream-server-blocks-vos-3000\">\u274c Problem 4: Registration Flooding \u2014 Upstream Server Blocks VOS3000<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udccb-complete-vos-3000-registration-parameter-quick-reference\">\ud83d\udccb Complete VOS3000 Registration Parameter Quick Reference<\/a><\/li><li><a href=\"#\ud83d\udca1-vos-3000-sip-outbound-registration-configuration-checklist\">\ud83d\udca1 VOS3000 SIP Outbound Registration Configuration Checklist<\/a><\/li><li><a href=\"#\u2753-frequently-asked-questions\">\u2753 Frequently Asked Questions<\/a><ul><li><a href=\"#\u2753-what-are-the-vos-3000-sip-outbound-registration-parameters\">\u2753 What are the VOS3000 SIP outbound registration parameters?<\/a><\/li><li><a href=\"#\u2753-should-i-use-auto-negotiation-or-a-fixed-registration-expiry\">\u2753 Should I use Auto Negotiation or a fixed registration expiry?<\/a><\/li><li><a href=\"#\u2753-what-is-the-recommended-retry-delay-for-primary-sip-trunks\">\u2753 What is the recommended retry delay for primary SIP trunks?<\/a><\/li><li><a href=\"#\u2753-what-happens-when-the-retry-delay-expires\">\u2753 What happens when the retry delay expires?<\/a><\/li><\/ul><\/li><li><a href=\"#\ud83d\udcde-need-expert-help-with-vos-3000-sip-outbound-registration\">\ud83d\udcde Need Expert Help with VOS3000 SIP Outbound Registration?<\/a><\/li><li><a href=\"#\ud83d\udcde-need-call-center-setup-support\">\ud83d\udcde Need Professional VOS3000 Setup Support?<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udd10-what-are-the-vos-3000-sip-outbound-registration-parameters\">\ud83d\udd10 What Are the VOS3000 SIP Outbound Registration Parameters?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udce1 The <strong>VOS3000 SIP outbound registration parameters<\/strong> control how VOS3000 registers to external SIP servers. When VOS3000 acts as a SIP User Agent and registers to another server, two timing parameters govern the complete registration lifecycle: \ud83d\udccb<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Parameter<\/th><th class=\"has-text-align-left\" data-align=\"left\">Default<\/th><th class=\"has-text-align-left\" data-align=\"left\">Range<\/th><th class=\"has-text-align-left\" data-align=\"left\">Purpose<\/th><\/tr><tr><td>\ud83d\udccc <strong>SS_SIP_USER_AGENT_EXPIRE<\/strong><\/td><td>Auto Negotiation<\/td><td>20\u20137200 seconds<\/td><td>SIP Registration Expiration Time to Other Server<\/td><\/tr><tr><td>\ud83d\udd04 <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong><\/td><td>60<\/td><td>30\u2013600 seconds<\/td><td>Resend Interval for SIP Registration when Failed<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udccd Both parameters are located at: <strong>Navigation \u2192 Operation management \u2192 Softswitch management \u2192 Additional settings \u2192 SIP parameter<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd11 <strong>Critical distinction:<\/strong> These parameters only apply to VOS3000&#8217;s <em>outbound<\/em> SIP registration \u2014 when VOS3000 registers <em>to<\/em> another server. They do <em>not<\/em> control how VOS3000 handles inbound registrations from your own endpoints. For inbound registration handling, see <a href=\"https:\/\/multahost.com\/blog\/vos3000-sip-registration\/\" target=\"_blank\" rel=\"noopener\">VOS3000 SIP registration<\/a> configuration. \ud83d\udce1<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\u23f1\ufe0f-ss-sip-user-agent-expire-registration-expiry\">\u23f1\ufe0f SS_SIP_USER_AGENT_EXPIRE \u2014 Registration Expiry<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udce1 The <strong>SS_SIP_USER_AGENT_EXPIRE<\/strong> parameter controls the SIP registration expiration time when VOS3000 registers to other servers. With a default of <strong>Auto Negotiation<\/strong> and a configurable range of <strong>20\u20137200 seconds<\/strong>, this setting is one of the most important parameters for maintaining stable outbound SIP trunking. Too short, and you flood the remote server with REGISTER messages. Too long, and NAT firewalls close the pinhole before re-registration occurs. \u2696\ufe0f<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Attribute<\/th><th class=\"has-text-align-left\" data-align=\"left\">Value<\/th><\/tr><tr><td>\ud83d\udccc Parameter Name<\/td><td>SS_SIP_USER_AGENT_EXPIRE<\/td><\/tr><tr><td>\ud83d\udd22 Default Value<\/td><td>Auto Negotiation<\/td><\/tr><tr><td>\ud83d\udcd0 Range<\/td><td>20\u20137200 seconds<\/td><\/tr><tr><td>\ud83d\udcdd Description<\/td><td>SIP Registration Expiration Time to Other Server<\/td><\/tr><tr><td>\ud83d\udccd Navigation<\/td><td>Operation management \u2192 Softswitch management \u2192 Additional settings \u2192 SIP parameter<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\ud83d\udd04-auto-negotiation-vs-fixed-expiry-how-it-works\">\ud83d\udd04 Auto Negotiation vs. Fixed Expiry \u2014 How It Works<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u2699\ufe0f The default &#8220;Auto Negotiation&#8221; mode follows a simple but effective principle: let the remote server decide. Here is how the negotiation process works: \ud83d\udce1<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">\ud83d\udce1 VOS3000 SIP Registration Expiry \u2014 Auto Negotiation Flow:\n\nVOS3000 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 Remote SIP Server\n   \u2502                                       \u2502\n   \u2502\u2500\u2500\u2500\u2500 REGISTER (Contact: expires=X) \u2500\u2500\u25ba\u2502\n   \u2502                                       \u2502\n   \u2502\u25c4\u2500\u2500\u2500 200 OK (Contact: expires=Y) \u2500\u2500\u2500\u2500\u2500\u2502\n   \u2502                                       \u2502\n   \u2502  \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510  \u2502\n   \u2502  \u2502 Auto Negotiation Mode:          \u2502  \u2502\n   \u2502  \u2502 \u2022 VOS3000 sends requested       \u2502  \u2502\n   \u2502  \u2502   expiry (X) in REGISTER        \u2502  \u2502\n   \u2502  \u2502 \u2022 Remote server responds with   \u2502  \u2502\n   \u2502  \u2502   accepted expiry (Y) in 200 OK \u2502  \u2502\n   \u2502  \u2502 \u2022 VOS3000 uses Y as the         \u2502  \u2502\n   \u2502  \u2502   effective registration expiry \u2502  \u2502\n   \u2502  \u2502 \u2022 Re-registration before Y      \u2502  \u2502\n   \u2502  \u2502   seconds elapse                \u2502  \u2502\n   \u2502  \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518  \u2502\n   \u2502                                       \u2502\n   \u2502  \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510  \u2502\n   \u2502  \u2502 Fixed Expiry Mode:              \u2502  \u2502\n   \u2502  \u2502 \u2022 VOS3000 forces specified      \u2502  \u2502\n   \u2502  \u2502   value (e.g., 300 seconds)     \u2502  \u2502\n   \u2502  \u2502 \u2022 VOS3000 re-registers at       \u2502  \u2502\n   \u2502  \u2502   ~50% of configured expiry     \u2502  \u2502\n   \u2502  \u2502   to prevent lapses             \u2502  \u2502\n   \u2502  \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518  \u2502\n<\/pre>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Expiry Mode<\/th><th class=\"has-text-align-left\" data-align=\"left\">Who Decides Expiry<\/th><th class=\"has-text-align-left\" data-align=\"left\">Best For<\/th><th class=\"has-text-align-left\" data-align=\"left\">Risk<\/th><\/tr><tr><td>\ud83e\udd1d Auto Negotiation<\/td><td>Remote server (200 OK)<\/td><td>General use, unknown providers<\/td><td>\u26a0\ufe0f NAT pinhole may close if server proposes long expiry<\/td><\/tr><tr><td>\ud83d\udccc Fixed Value (e.g., 300s)<\/td><td>VOS3000 (you control it)<\/td><td>NAT environments, predictable timing<\/td><td>\u26a0\ufe0f Value may conflict with remote server&#8217;s minimum\/maximum<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>NAT pro tip:<\/strong> If VOS3000 is behind a NAT firewall and registering to an external server, always set a fixed registration expiry of <strong>120\u2013300 seconds<\/strong> rather than using Auto Negotiation. If the remote server proposes a long expiry (e.g., 3600 seconds), your NAT mapping may expire before the next re-registration, silently breaking inbound calls. This is the single most common cause of &#8220;my trunk works for a while and then stops&#8221; complaints. \ud83d\udd27<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udd04-ss-sip-user-agent-retry-delay-registration-failure-retry\">\ud83d\udd04 SS_SIP_USER_AGENT_RETRY_DELAY \u2014 Registration Failure Retry<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u23f1\ufe0f When an outbound registration fails (e.g., the remote server returns 403 Forbidden, 401 Unauthorized, or is simply unreachable), VOS3000 waits <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong> seconds before attempting to re-register. The default is <strong>60 seconds<\/strong> with a range of <strong>30\u2013600 seconds<\/strong>. \ud83d\udd01<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Attribute<\/th><th class=\"has-text-align-left\" data-align=\"left\">Value<\/th><\/tr><tr><td>\ud83d\udccc Parameter Name<\/td><td>SS_SIP_USER_AGENT_RETRY_DELAY<\/td><\/tr><tr><td>\ud83d\udd22 Default Value<\/td><td>60<\/td><\/tr><tr><td>\ud83d\udcd0 Range<\/td><td>30\u2013600 seconds<\/td><\/tr><tr><td>\ud83d\udcdd Description<\/td><td>Resend Interval for SIP Registration when Failed<\/td><\/tr><tr><td>\ud83d\udccd Navigation<\/td><td>Operation management \u2192 Softswitch management \u2192 Additional settings \u2192 SIP parameter<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcca <strong>Key behavior:<\/strong> VOS3000 does <em>not<\/em> implement exponential backoff for registration retries. Each failed attempt waits the same fixed <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong> interval before retrying. This means if you set the delay to 60 seconds, VOS3000 will attempt re-registration every 60 seconds consistently until the registration succeeds. \u23f1\ufe0f<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\ud83d\udd04-retry-delay-vs-registration-expiry-key-difference\">\ud83d\udd04 Retry Delay vs. Registration Expiry \u2014 Key Difference<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u26a0\ufe0f A common source of confusion is the difference between these two parameters: \ud83c\udfaf<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Aspect<\/th><th class=\"has-text-align-left\" data-align=\"left\">SS_SIP_USER_AGENT_RETRY_DELAY<\/th><th class=\"has-text-align-left\" data-align=\"left\">SS_SIP_USER_AGENT_EXPIRE<\/th><\/tr><tr><td>\ud83d\udccc Purpose<\/td><td>Wait time <em>after registration failure<\/em><\/td><td>Registration <em>validity duration<\/em> on success<\/td><\/tr><tr><td>\ud83d\udd22 Default<\/td><td>60 seconds<\/td><td>Auto Negotiation (20\u20137200s)<\/td><\/tr><tr><td>\ud83d\udd04 Triggered When<\/td><td>Registration FAILS (timeout, 403, 503, etc.)<\/td><td>Registration SUCCEEDS (200 OK received)<\/td><\/tr><tr><td>\ud83d\udcca Effect<\/td><td>Determines re-registration attempt interval<\/td><td>Determines when VOS3000 refreshes a valid registration<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>Simple rule:<\/strong> Retry delay governs &#8220;how long to wait before trying again after failure.&#8221; Expiry governs &#8220;how long my successful registration remains valid before I need to refresh it.&#8221; For more on the expiry parameter, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-outbound-registration-sip\/\" target=\"_blank\" rel=\"noopener\">outbound registration SIP<\/a> guide. \ud83d\udce1<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udccb-companion-user-agent-registration-parameters\">\ud83d\udccb Companion User Agent Registration Parameters<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd17 The expiry and retry delay do not work alone. Two additional parameters control the unregistration and privacy behavior of outbound registrations: \ud83d\udee1\ufe0f<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Parameter<\/th><th class=\"has-text-align-left\" data-align=\"left\">Default<\/th><th class=\"has-text-align-left\" data-align=\"left\">Options<\/th><th class=\"has-text-align-left\" data-align=\"left\">Description<\/th><\/tr><tr><td>\ud83d\udce4 SS_SIP_USER_AGENT_SEND_UNREGISTER<\/td><td>On<\/td><td>On \/ Off<\/td><td>Send Cancel Register Message on restart\/shutdown<\/td><\/tr><tr><td>\ud83d\udd12 SS_SIP_USER_AGENT_PRIVACY<\/td><td>Ignore<\/td><td>Ignore \/ Id \/ None<\/td><td>Privacy Setting for Register User<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd0c <strong>SS_SIP_USER_AGENT_SEND_UNREGISTER:<\/strong> When this parameter is <strong>On<\/strong> (the default), VOS3000 sends a SIP REGISTER with <strong>Expires: 0<\/strong> to the remote server when the registration is removed or the system shuts down. This cleanly de-registers VOS3000, freeing resources on both sides. Keep this On \u2014 disabling it means the remote server retains the registration until it naturally expires, which can cause the remote server to route calls to a VOS3000 that is no longer available. For more on how authentication interacts with registration, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-sip-authentication\/\" target=\"_blank\" rel=\"noopener\">VOS3000 SIP authentication<\/a> guide. \ud83d\udd10<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udee1\ufe0f <strong>SS_SIP_USER_AGENT_PRIVACY:<\/strong> Controls how the SIP Privacy header is included in outbound REGISTER messages. The default <strong>Ignore<\/strong> means VOS3000 does not include any Privacy header. <strong>Id<\/strong> includes &#8220;Privacy: id&#8221; to request identity privacy. <strong>None<\/strong> includes &#8220;Privacy: none&#8221; to explicitly request no privacy handling. \ud83d\udd12<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udce1-endpoint-registration-expiry-the-other-side-of-the-coin\">\ud83d\udce1 Endpoint Registration Expiry \u2014 The Other Side of the Coin<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd04 While SS_SIP_USER_AGENT_EXPIRE controls how VOS3000 registers <strong>to other servers<\/strong>, the endpoint registration parameters control how <strong>external devices register to VOS3000<\/strong>. Understanding the difference is critical for proper VOS3000 SIP outbound registration parameters management. \u2696\ufe0f<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Aspect<\/th><th class=\"has-text-align-left\" data-align=\"left\">User Agent Expiry (Outbound)<\/th><th class=\"has-text-align-left\" data-align=\"left\">Endpoint Expiry (Inbound)<\/th><\/tr><tr><td>\ud83d\udccc Parameter<\/td><td>SS_SIP_USER_AGENT_EXPIRE<\/td><td>SS_ENDPOINT_EXPIRE \/ SS_ENDPOINT_NAT_EXPIRE<\/td><\/tr><tr><td>\ud83d\udce1 Direction<\/td><td>VOS3000 \u2192 Other Server<\/td><td>Device \u2192 VOS3000<\/td><\/tr><tr><td>\ud83d\udd22 Default<\/td><td>Auto Negotiation<\/td><td>300 \/ 3600 (NAT: 300)<\/td><\/tr><tr><td>\u26a0\ufe0f Failure Impact<\/td><td>Outbound\/inbound calls via that trunk fail<\/td><td>Device appears unregistered, cannot receive calls<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>Rule of thumb:<\/strong> If VOS3000 is registering to someone else, think SS_SIP_USER_AGENT_EXPIRE. If someone is registering to VOS3000, think SS_ENDPOINT_EXPIRE. For detailed coverage of endpoint-side registration, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-registration-flood\/\" target=\"_blank\" rel=\"noopener\">registration flood protection<\/a> guide. \ud83c\udf10<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\ud83d\udd10-system-level-endpoint-retry-parameters\">\ud83d\udd10 System-Level Endpoint Retry Parameters<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcca While SS_SIP_USER_AGENT_RETRY_DELAY controls VOS3000&#8217;s <em>outbound<\/em> registration retries, VOS3000 also provides system-level parameters that govern <em>inbound<\/em> terminal registration failure handling: \ud83d\udccb<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Parameter<\/th><th class=\"has-text-align-left\" data-align=\"left\">Default<\/th><th class=\"has-text-align-left\" data-align=\"left\">Description<\/th><\/tr><tr><td>SS_ENDPOINT_REGISTER_RETRY<\/td><td>6<\/td><td>Max retry times when terminal registration<\/td><\/tr><tr><td>SS_ENDPOINT_REGISTER_SUSPEND<\/td><td>180<\/td><td>Disable duration after exceeding retry times<\/td><\/tr><tr><td>SS_ENDPOINT_REGISTER_REPLACE<\/td><td>On<\/td><td>Allow replace current registered users<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcde For detailed configuration of endpoint registration behavior and suspension, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-authentication-suspend\/\" target=\"_blank\" rel=\"noopener\">VOS3000 authentication suspend<\/a> guide. For system-level parameter documentation, refer to <a href=\"https:\/\/multahost.com\/blog\/vos3000-system-parameters\/\" target=\"_blank\" rel=\"noopener\">VOS3000 system parameters<\/a>. \ud83d\udcd6<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udd04-vos-3000-sip-outbound-registration-and-server-redundancy\">\ud83d\udd04 VOS3000 SIP Outbound Registration and Server Redundancy<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udda5\ufe0f One of the most critical applications of the <strong>VOS3000 SIP outbound registration parameters<\/strong> is in server redundancy and failover scenarios. When VOS3000 is configured to register with an upstream SIP proxy and that proxy becomes unavailable, the retry delay determines how quickly VOS3000 attempts to re-establish the registration \u2014 which directly impacts your call routing availability. \ud83c\udf10<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\ud83d\udce1-failover-timing-analysis\">\ud83d\udce1 Failover Timing Analysis<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u23f1\ufe0f Consider a scenario where VOS3000 is registered to a primary SIP trunk and the upstream server goes down. Here is how the retry delay affects recovery time: \ud83d\udcca<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Retry Delay<\/th><th class=\"has-text-align-left\" data-align=\"left\">First Retry After<\/th><th class=\"has-text-align-left\" data-align=\"left\">Max Downtime (5 retries)<\/th><th class=\"has-text-align-left\" data-align=\"left\">Network Load<\/th><th class=\"has-text-align-left\" data-align=\"left\">Best For<\/th><\/tr><tr><td>30s (minimum)<\/td><td>30 seconds<\/td><td>~2.5 minutes<\/td><td>\ud83d\udd34 Higher<\/td><td>\u26a1 Mission-critical trunks<\/td><\/tr><tr><td>60s (default)<\/td><td>60 seconds<\/td><td>~5 minutes<\/td><td>\ud83d\udfe1 Moderate<\/td><td>\ud83d\udcca Standard deployments<\/td><\/tr><tr><td>120s<\/td><td>120 seconds<\/td><td>~10 minutes<\/td><td>\ud83d\udfe2 Lower<\/td><td>\ud83c\udfe2 Stable enterprise links<\/td><\/tr><tr><td>300s<\/td><td>5 minutes<\/td><td>~25 minutes<\/td><td>\ud83d\udfe2 Very Low<\/td><td>\ud83d\udce1 Backup trunks only<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83c\udfaf <strong>Failover strategy:<\/strong> For primary SIP trunks where call availability is critical, use the minimum 30-second retry delay. For backup or secondary trunks, a longer delay (120-300 seconds) reduces unnecessary network traffic. For a complete failover setup guide, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-vendor-failover-setup\/\" target=\"_blank\" rel=\"noopener\">VOS3000 vendor failover setup<\/a>. \ud83d\udee1\ufe0f<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udd27-step-by-step-vos-3000-sip-outbound-registration-configuration\">\ud83d\udd27 Step-by-Step VOS3000 SIP Outbound Registration Configuration<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u2699\ufe0f Follow these steps to configure both outbound registration parameters and their companions:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step-1-configure-global-ss-sip-user-agent-expire-\ud83d\udccb\">Step 1: Configure Global SS_SIP_USER_AGENT_EXPIRE \ud83d\udccb<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\ud83d\udd10 Log in to VOS3000 Client<\/li>\n\n\n\n<li>\ud83d\udccc Navigate: <strong>Operation management \u2192 Softswitch management \u2192 Additional settings \u2192 SIP parameter<\/strong><\/li>\n\n\n\n<li>\ud83d\udd0d Locate <strong>SS_SIP_USER_AGENT_EXPIRE<\/strong> in the parameter list<\/li>\n\n\n\n<li>\u270f\ufe0f Choose <strong>Auto Negotiation<\/strong> (default) or set a specific value between 20\u20137200 seconds<\/li>\n\n\n\n<li>\ud83d\udcbe Save and apply the changes<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step-2-configure-ss-sip-user-agent-retry-delay-\ud83d\udd04\">Step 2: Configure SS_SIP_USER_AGENT_RETRY_DELAY \ud83d\udd04<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\ud83d\udccc In the same SIP parameter section, locate <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong><\/li>\n\n\n\n<li>\u270f\ufe0f Set the desired value (range: 30\u2013600 seconds, default: 60)<\/li>\n\n\n\n<li>\ud83d\udcbe Save changes<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step-3-configure-companion-parameters-\ud83d\udd17\">Step 3: Configure Companion Parameters \ud83d\udd17<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\ud83d\udd0d Verify <strong>SS_SIP_USER_AGENT_SEND_UNREGISTER<\/strong> is On (default) for clean disconnection<\/li>\n\n\n\n<li>\ud83d\udd0d Set <strong>SS_SIP_USER_AGENT_PRIVACY<\/strong> to Ignore (default) unless provider requires a specific privacy header<\/li>\n\n\n\n<li>\ud83d\udcbe Save all changes<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step-4-configure-per-registration-settings-\ud83d\udda5\ufe0f\">Step 4: Configure Per-Registration Settings \ud83d\udda5\ufe0f<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\ud83d\udccc Navigate to the outbound registration management page<\/li>\n\n\n\n<li>\ud83d\udd0d Select the registration entry for your upstream provider<\/li>\n\n\n\n<li>\u270f\ufe0f Configure <strong>Register period<\/strong> \u2014 choose Auto negotiation or a specific value<\/li>\n\n\n\n<li>\ud83d\udd0c Set the <strong>Signaling port<\/strong> of the remote registration server<\/li>\n\n\n\n<li>\ud83c\udf10 Enter the <strong>SIP proxy<\/strong> address<\/li>\n\n\n\n<li>\ud83d\udcbe Save the registration settings<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"step-5-verify-registration-with-sip-debug-\ud83d\udd0d\">Step 5: Verify Registration with SIP Debug \ud83d\udd0d<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcdd After configuration, verify the registration is working correctly. For comprehensive debugging instructions, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-troubleshooting-guide-2026\/\" target=\"_blank\" rel=\"noopener\">VOS3000 troubleshooting guide<\/a>. \ud83d\udd27<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udcca-vos-3000-sip-outbound-registration-best-practices-by-scenario\">\ud83d\udcca VOS3000 SIP Outbound Registration Best Practices by Scenario<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83c\udfaf Different deployment scenarios require different registration expiry and retry delay combinations. Here are our recommendations: \ud83d\udca1<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Scenario<\/th><th class=\"has-text-align-left\" data-align=\"left\">Expiry<\/th><th class=\"has-text-align-left\" data-align=\"left\">Retry Delay<\/th><th class=\"has-text-align-left\" data-align=\"left\">Rationale<\/th><\/tr><tr><td>\ud83c\udf10 NAT environment<\/td><td>120\u2013300 seconds<\/td><td>30\u201360 seconds<\/td><td>Short enough to keep NAT pinhole open; long enough to avoid flooding<\/td><\/tr><tr><td>\ud83c\udfe2 Same LAN \/ data center<\/td><td>600\u20133600 seconds<\/td><td>60 seconds<\/td><td>No NAT concerns; longer expiry reduces REGISTER traffic<\/td><\/tr><tr><td>\ud83d\udce1 Wholesale carrier trunk<\/td><td>Auto Negotiation<\/td><td>60 seconds<\/td><td>Let the carrier decide; they know their requirements best<\/td><\/tr><tr><td>\ud83d\udee1\ufe0f Unstable network link<\/td><td>60\u2013120 seconds<\/td><td>30 seconds<\/td><td>Fast recovery; short retry delay for quick re-registration after link recovery<\/td><\/tr><tr><td>\ud83d\udd0c Multiple trunks to same provider<\/td><td>300\u2013600 seconds<\/td><td>60 seconds<\/td><td>Moderate expiry; avoid all trunks re-registering simultaneously<\/td><\/tr><tr><td>\ud83d\udd04 Primary SIP trunk (carrier)<\/td><td>120\u2013300 seconds<\/td><td>30\u201345 seconds<\/td><td>Fast recovery needed; minimize call disruption on primary routes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udee1\ufe0f-common-vos-3000-sip-outbound-registration-problems-and-solutions\">\ud83d\udee1\ufe0f Common VOS3000 SIP Outbound Registration Problems and Solutions<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u26a0\ufe0f Misconfigured outbound registration parameters cause a range of issues. Here are the most common problems and their solutions:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u274c-problem-1-trunk-works-then-silently-stops-receiving-calls\">\u274c Problem 1: Trunk Works Then Silently Stops Receiving Calls<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd0d <strong>Symptom:<\/strong> Outbound calls work fine, but inbound calls via the trunk start failing after some time (typically 5\u201330 minutes after registration).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>Cause:<\/strong> VOS3000 is behind NAT and the registration expiry is too long. The NAT firewall closes the UDP pinhole before VOS3000 re-registers. \ud83c\udf10<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u2705 <strong>Solutions:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ud83d\udd27 Change SS_SIP_USER_AGENT_EXPIRE from Auto Negotiation to a fixed value of <strong>120\u2013300 seconds<\/strong><\/li>\n\n\n\n<li>\ud83d\udce1 Verify NAT keep-alive is enabled \u2014 see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-sip-session\/\" target=\"_blank\" rel=\"noopener\">SIP session<\/a> guide for session timer settings<\/li>\n\n\n\n<li>\ud83d\udd0d Check SIP debug to confirm re-registration occurs before the NAT mapping expires<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u274c-problem-2-excessive-register-messages-flooding-the-network\">\u274c Problem 2: Excessive REGISTER Messages Flooding the Network<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd0d <strong>Symptom:<\/strong> SIP traces show VOS3000 sending REGISTER messages every few seconds, even when the registration is successful.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>Cause:<\/strong> SS_SIP_USER_AGENT_EXPIRE is set to a very low value (e.g., 20 seconds), causing VOS3000 to re-register extremely frequently. \ud83d\udcca<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u2705 <strong>Solutions:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u23f1\ufe0f Increase SS_SIP_USER_AGENT_EXPIRE to at least <strong>120 seconds<\/strong><\/li>\n\n\n\n<li>\ud83d\udccb Check if Auto Negotiation is resulting in a very short server-proposed expiry<\/li>\n\n\n\n<li>\ud83d\udd04 If the provider requires short expiry, verify SS_SIP_USER_AGENT_RETRY_DELAY is not adding unnecessary re-registration attempts<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u274c-problem-3-registration-fails-and-never-recovers\">\u274c Problem 3: Registration Fails and Never Recovers<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd0d <strong>Symptom:<\/strong> After a network outage or server restart, VOS3000 does not re-register to the remote server.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>Cause:<\/strong> SS_SIP_USER_AGENT_RETRY_DELAY may be set too high, or the authentication credentials may be wrong. \ud83d\udd10<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u2705 <strong>Solutions:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ud83d\udd04 Set SS_SIP_USER_AGENT_RETRY_DELAY to <strong>60 seconds<\/strong> for reasonable retry timing<\/li>\n\n\n\n<li>\ud83d\udd10 Verify SIP authentication credentials are correct \u2014 see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-sip-authentication\/\" target=\"_blank\" rel=\"noopener\">SIP authentication<\/a> guide<\/li>\n\n\n\n<li>\ud83d\udccb Check if the remote server has blocked your IP due to excessive registration failures<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u274c-problem-4-registration-flooding-upstream-server-blocks-vos-3000\">\u274c Problem 4: Registration Flooding \u2014 Upstream Server Blocks VOS3000<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd0d <strong>Symptom:<\/strong> Upstream carrier reports excessive registration requests from your VOS3000; possibly blocks your IP or suspends your trunk.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udca1 <strong>Cause:<\/strong> SS_SIP_USER_AGENT_RETRY_DELAY is set too low (30 seconds) and the upstream server is experiencing transient issues, causing VOS3000 to send a REGISTER every 30 seconds continuously.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u2705 <strong>Solutions:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ud83d\udd27 Increase SS_SIP_USER_AGENT_RETRY_DELAY to 60\u2013120 seconds<\/li>\n\n\n\n<li>\ud83d\udcde Contact the upstream carrier to understand their registration rate limits<\/li>\n\n\n\n<li>\ud83d\udcca Monitor registration attempt frequency in VOS3000 logs<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udccb-complete-vos-3000-registration-parameter-quick-reference\">\ud83d\udccb Complete VOS3000 Registration Parameter Quick Reference<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcca Here is the complete reference for all parameters that govern SIP registration behavior in VOS3000 \u2014 both outbound (User Agent) and inbound (Endpoint): \ud83d\udccb<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Parameter<\/th><th class=\"has-text-align-left\" data-align=\"left\">Default<\/th><th class=\"has-text-align-left\" data-align=\"left\">Direction<\/th><th class=\"has-text-align-left\" data-align=\"left\">Function<\/th><\/tr><tr><td>\ud83d\udccc <strong>SS_SIP_USER_AGENT_EXPIRE<\/strong><\/td><td>Auto (20\u20137200s)<\/td><td>Outbound<\/td><td>Registration expiry to other server<\/td><\/tr><tr><td>\ud83d\udd04 <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong><\/td><td>60s (30\u2013600s)<\/td><td>Outbound<\/td><td>Wait time before re-registering after failure<\/td><\/tr><tr><td>\ud83d\udce4 SS_SIP_USER_AGENT_SEND_UNREGISTER<\/td><td>On<\/td><td>Outbound<\/td><td>Send cancel register on restart<\/td><\/tr><tr><td>\ud83d\udd12 SS_SIP_USER_AGENT_PRIVACY<\/td><td>Ignore<\/td><td>Outbound<\/td><td>Privacy setting for register user<\/td><\/tr><tr><td>\ud83d\udda5\ufe0f SS_ENDPOINT_EXPIRE<\/td><td>300 \/ 3600<\/td><td>Inbound<\/td><td>Terminal registration expiry time<\/td><\/tr><tr><td>\ud83c\udf10 SS_ENDPOINT_NAT_EXPIRE<\/td><td>300<\/td><td>Inbound<\/td><td>Terminal registration expiry time (NAT)<\/td><\/tr><tr><td>\ud83d\udd01 SS_ENDPOINT_REGISTER_RETRY<\/td><td>6<\/td><td>Inbound<\/td><td>Max retry times for terminal registration<\/td><\/tr><tr><td>\u23f8\ufe0f SS_ENDPOINT_REGISTER_SUSPEND<\/td><td>180s<\/td><td>Inbound<\/td><td>Disable duration after exceeding retries<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd27 For complete documentation on all SIP parameters, see our <a href=\"https:\/\/multahost.com\/blog\/vos3000-parameter-description\/\" target=\"_blank\" rel=\"noopener\">VOS3000 parameter description<\/a> reference. \ud83d\udcd6<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udca1-vos-3000-sip-outbound-registration-configuration-checklist\">\ud83d\udca1 VOS3000 SIP Outbound Registration Configuration Checklist<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u2705 Use this checklist when deploying or tuning your VOS3000 SIP outbound registration parameters:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th class=\"has-text-align-left\" data-align=\"left\">Check<\/th><th class=\"has-text-align-left\" data-align=\"left\">Action<\/th><th class=\"has-text-align-left\" data-align=\"left\">Status<\/th><\/tr><tr><td>\ud83d\udccc 1<\/td><td>Set SS_SIP_USER_AGENT_EXPIRE \u2014 Auto Negotiation or fixed value (120\u2013300s for NAT)<\/td><td>\u2610<\/td><\/tr><tr><td>\ud83d\udccc 2<\/td><td>Set SS_SIP_USER_AGENT_RETRY_DELAY \u2014 60s default, 30\u201345s for primary trunks<\/td><td>\u2610<\/td><\/tr><tr><td>\ud83d\udccc 3<\/td><td>Verify SS_SIP_USER_AGENT_SEND_UNREGISTER is On for clean restart behavior<\/td><td>\u2610<\/td><\/tr><tr><td>\ud83d\udccc 4<\/td><td>Configure backup vendor gateways for failover during retry periods<\/td><td>\u2610<\/td><\/tr><tr><td>\ud83d\udccc 5<\/td><td>Test registration failover by temporarily disabling upstream server<\/td><td>\u2610<\/td><\/tr><tr><td>\ud83d\udccc 6<\/td><td>Monitor SIP debug trace to confirm retry delay matches configured value<\/td><td>\u2610<\/td><\/tr><tr><td>\ud83d\udccc 7<\/td><td>Verify authentication user credentials in gateway configuration<\/td><td>\u2610<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\u2753-frequently-asked-questions\">\u2753 Frequently Asked Questions<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u2753-what-are-the-vos-3000-sip-outbound-registration-parameters\">\u2753 What are the VOS3000 SIP outbound registration parameters?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udce1 The VOS3000 SIP outbound registration parameters are <strong>SS_SIP_USER_AGENT_EXPIRE<\/strong> (default: Auto Negotiation, range: 20\u20137200 seconds) and <strong>SS_SIP_USER_AGENT_RETRY_DELAY<\/strong> (default: 60 seconds, range: 30\u2013600 seconds). The expiry parameter controls how long a successful registration remains valid, while the retry delay controls how long VOS3000 waits before re-registering after a failure. Together, they govern the complete lifecycle of VOS3000&#8217;s outbound SIP registration to other servers. \ud83d\udd27<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u2753-should-i-use-auto-negotiation-or-a-fixed-registration-expiry\">\u2753 Should I use Auto Negotiation or a fixed registration expiry?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u2696\ufe0f Use <strong>Auto Negotiation<\/strong> when VOS3000 is in the same data center as the remote server (no NAT) and you want maximum compatibility. Use a <strong>fixed value of 120\u2013300 seconds<\/strong> when VOS3000 is behind a NAT firewall \u2014 this is critical because Auto Negotiation may result in a long expiry (e.g., 3600 seconds) that allows the NAT mapping to expire before the next re-registration, silently breaking inbound calls. \ud83d\udd27<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u2753-what-is-the-recommended-retry-delay-for-primary-sip-trunks\">\u2753 What is the recommended retry delay for primary SIP trunks?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u26a1 For primary SIP trunks where call availability is critical, use <strong>30\u201345 seconds<\/strong>. This provides fast recovery after server outages. For backup or secondary trunks, a longer delay of 120\u2013300 seconds reduces unnecessary network traffic. The default 60 seconds is a reasonable balance for standard deployments. \u23f1\ufe0f<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"\u2753-what-happens-when-the-retry-delay-expires\">\u2753 What happens when the retry delay expires?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd04 When the retry delay timer expires, VOS3000 sends a new SIP REGISTER request to the upstream server. If the registration succeeds (200 OK), normal operation resumes. If it fails again, the retry delay timer starts again and VOS3000 will retry after the same fixed interval. This continues until the registration succeeds. \u2699\ufe0f<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udcde-need-expert-help-with-vos-3000-sip-outbound-registration\">\ud83d\udcde Need Expert Help with VOS3000 SIP Outbound Registration?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udd27 Configuring the VOS3000 SIP outbound registration parameters correctly is essential for maintaining stable SIP trunking, fast failover recovery, and reliable inbound call delivery. Whether you need help with NAT-friendly registration expiry tuning, retry delay optimization, or troubleshooting registration failures, our team is ready to assist. \ud83d\udee1\ufe0f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcac <strong>WhatsApp:<\/strong> <a href=\"https:\/\/wa.me\/8801911119966\" target=\"_blank\" rel=\"noopener\">+8801911119966<\/a> | \ud83d\udcde <strong>Phone:<\/strong> +8801911119966<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"\ud83d\udcde-need-call-center-setup-support\">\ud83d\udcde Need Professional VOS3000 Setup Support?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">For professional VOS3000 installations and deployment, VOS3000 Server Rental Solution:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udcf1 <strong>WhatsApp:<\/strong> <a href=\"https:\/\/wa.me\/8801911119966\" target=\"_blank\" rel=\"noopener\">+8801911119966<\/a><br>\ud83c\udf10 <strong>Website:<\/strong> <a href=\"https:\/\/www.vos3000.com\">www.vos3000.com<\/a><br>\ud83c\udf10 <strong>Blog:<\/strong> <a href=\"https:\/\/multahost.com\/blog\" target=\"_blank\" rel=\"noopener\">multahost.com\/blog<\/a><br>\ud83d\udce5 <strong>Downloads:<\/strong> <a href=\"https:\/\/www.vos3000.com\/downloads.php\">VOS3000 Downloads<\/a><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><img decoding=\"async\" src=\"https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Authentication-Retry-VOS3000-SIP-Early-Hangup-VOS3000-SIP-Session-Timer-Refresh-VOS3000-Non-Timer-Endpoint-Safety-VOS3000-SIP-NAT-Keepalive-1-1024x683.png\" alt=\"VOS3000 SIP Authentication Retry, VOS3000 SIP Early Hangup, VOS3000 SIP Session Timer Refresh, VOS3000 Non-Timer Endpoint Safety, VOS3000 SIP NAT Keepalive, VOS3000 SIP Resend Interval, VOS3000 SIP INVITE Timeout, VOS3000 SIP Call Progress Timeout, VOS3000 SIP Outbound Registration Parameters, VOS3000 SIP Privacy Header, VOS3000 SIP Routing Gateway Contact, VOS3000 SIP Publish Expire, VOS3000 SIP Display From, VOS3000 SIP Send Unregister\"><\/td><td><img decoding=\"async\" src=\"https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Authentication-Retry-VOS3000-SIP-Early-Hangup-VOS3000-SIP-Session-Timer-Refresh-VOS3000-Non-Timer-Endpoint-Safety-VOS3000-SIP-NAT-Keepalive-1-1024x683.png\" alt=\"VOS3000 SIP Authentication Retry, VOS3000 SIP Early Hangup, VOS3000 SIP Session Timer Refresh, VOS3000 Non-Timer Endpoint Safety, VOS3000 SIP NAT Keepalive, VOS3000 SIP Resend Interval, VOS3000 SIP INVITE Timeout, VOS3000 SIP Call Progress Timeout, VOS3000 SIP Outbound Registration Parameters, VOS3000 SIP Privacy Header, VOS3000 SIP Routing Gateway Contact, VOS3000 SIP Publish Expire, VOS3000 SIP Display From, VOS3000 SIP Send Unregister\"><\/td><td><img decoding=\"async\" src=\"https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Authentication-Retry-VOS3000-SIP-Early-Hangup-VOS3000-SIP-Session-Timer-Refresh-VOS3000-Non-Timer-Endpoint-Safety-VOS3000-SIP-NAT-Keepalive-1-1024x683.png\" alt=\"VOS3000 SIP Authentication Retry, VOS3000 SIP Early Hangup, VOS3000 SIP Session Timer Refresh, VOS3000 Non-Timer Endpoint Safety, VOS3000 SIP NAT Keepalive, VOS3000 SIP Resend Interval, VOS3000 SIP INVITE Timeout, VOS3000 SIP Call Progress Timeout, VOS3000 SIP Outbound Registration Parameters, VOS3000 SIP Privacy Header, VOS3000 SIP Routing Gateway Contact, VOS3000 SIP Publish Expire, VOS3000 SIP Display From, VOS3000 SIP Send Unregister\"><\/td><\/tr><\/tbody><\/table><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Master VOS3000 SIP outbound registration parameters: SS_SIP_USER_AGENT_EXPIRE (Auto Negotiation, 20-7200s) and SS_SIP_USER_AGENT_RETRY_DELAY (30-600s). Configure registration expiry, retry delay, and failover for stable SIP trunking.<\/p>\n","protected":false},"author":1,"featured_media":1297,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kadence_starter_templates_imported_post":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[2],"tags":[7193,7191,7195,7208,7201,7230,7220,7192,7042,7194,7202,7226,591,7197,7209,7190,7223,7214,7205,2647,7224,7213,7210,7222,7189,7218,7216,7196,7198,7203,7221,7206,7200,6091,7225,7207,7215,7212,7211,7228,7227,7199,7217,7204,7219,7229],"class_list":["post-1300","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-vos3000","tag-ss_sip_user_agent_expire","tag-ss_sip_user_agent_retry_delay","tag-vos3000-auto-negotiation-registration","tag-vos3000-contact-header-expiry","tag-vos3000-nat-registration-keep-alive","tag-vos3000-operation-management-sip","tag-vos3000-outbound-registration-stability","tag-vos3000-outbound-sip-registration","tag-vos3000-registration-expiry","tag-vos3000-registration-failover","tag-vos3000-registration-failure-retry","tag-vos3000-registration-flood-protection","tag-vos3000-registration-management","tag-vos3000-registration-recovery-timing","tag-vos3000-registration-renewal","tag-vos3000-registration-retry-delay","tag-vos3000-registration-retry-delay-60-seconds","tag-vos3000-registration-retry-interval","tag-vos3000-registration-to-other-server","tag-vos3000-registration-troubleshooting","tag-vos3000-server-redundancy-registration","tag-vos3000-signaling-port-registration","tag-vos3000-sip-expire-header","tag-vos3000-sip-expire-negotiation","tag-vos3000-sip-outbound-registration-parameters","tag-vos3000-sip-privacy-registration","tag-vos3000-sip-proxy-registration","tag-vos3000-sip-re-registration","tag-vos3000-sip-register-expire","tag-vos3000-sip-register-message","tag-vos3000-sip-registration-best-practices","tag-vos3000-sip-registration-configuration","tag-vos3000-sip-registration-interval","tag-vos3000-sip-trunk-registration","tag-vos3000-sip-trunk-stability","tag-vos3000-softswitch-registration","tag-vos3000-ss_endpoint_expire","tag-vos3000-ss_endpoint_register_retry","tag-vos3000-ss_endpoint_register_suspend","tag-vos3000-ss_sip_user_agent_privacy","tag-vos3000-ss_sip_user_agent_send_unregister","tag-vos3000-user-agent-expire","tag-vos3000-user-agent-unregister","tag-vos3000-vendor-registration-timeout","tag-vos3000-voip-registration-timer","tag-vos3000-voip-softswitch-registration"],"acf":[],"jetpack_featured_media_url":"https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters.png","blog_post_layout_featured_media_urls":{"thumbnail":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-150x150.png",150,150,true],"full":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters.png",1536,1024,false]},"categories_names":{"2":{"name":"VOS3000`","link":"https:\/\/www.vos3000.com\/blog\/category\/vos3000\/"}},"tags_names":{"7193":{"name":"SS_SIP_USER_AGENT_EXPIRE","link":"https:\/\/www.vos3000.com\/blog\/tag\/ss_sip_user_agent_expire\/"},"7191":{"name":"SS_SIP_USER_AGENT_RETRY_DELAY","link":"https:\/\/www.vos3000.com\/blog\/tag\/ss_sip_user_agent_retry_delay\/"},"7195":{"name":"VOS3000 auto negotiation registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-auto-negotiation-registration\/"},"7208":{"name":"VOS3000 Contact header expiry","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-contact-header-expiry\/"},"7201":{"name":"VOS3000 NAT registration keep alive","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-nat-registration-keep-alive\/"},"7230":{"name":"VOS3000 operation management SIP","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-operation-management-sip\/"},"7220":{"name":"VOS3000 outbound registration stability","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-outbound-registration-stability\/"},"7192":{"name":"VOS3000 outbound SIP registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-outbound-sip-registration\/"},"7042":{"name":"VOS3000 registration expiry","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-expiry\/"},"7194":{"name":"VOS3000 registration failover","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-failover\/"},"7202":{"name":"VOS3000 registration failure retry","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-failure-retry\/"},"7226":{"name":"VOS3000 registration flood protection","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-flood-protection\/"},"591":{"name":"VOS3000 registration management","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-management\/"},"7197":{"name":"VOS3000 registration recovery timing","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-recovery-timing\/"},"7209":{"name":"VOS3000 registration renewal","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-renewal\/"},"7190":{"name":"VOS3000 registration retry delay","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-retry-delay\/"},"7223":{"name":"VOS3000 registration retry delay 60 seconds","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-retry-delay-60-seconds\/"},"7214":{"name":"VOS3000 registration retry interval","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-retry-interval\/"},"7205":{"name":"VOS3000 registration to other server","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-to-other-server\/"},"2647":{"name":"VOS3000 registration troubleshooting","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-registration-troubleshooting\/"},"7224":{"name":"VOS3000 server redundancy registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-server-redundancy-registration\/"},"7213":{"name":"VOS3000 signaling port registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-signaling-port-registration\/"},"7210":{"name":"VOS3000 SIP expire header","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-expire-header\/"},"7222":{"name":"VOS3000 SIP expire negotiation","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-expire-negotiation\/"},"7189":{"name":"VOS3000 SIP outbound registration parameters","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-outbound-registration-parameters\/"},"7218":{"name":"VOS3000 SIP privacy registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-privacy-registration\/"},"7216":{"name":"VOS3000 SIP proxy registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-proxy-registration\/"},"7196":{"name":"VOS3000 SIP re-registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-re-registration\/"},"7198":{"name":"VOS3000 SIP register expire","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-register-expire\/"},"7203":{"name":"VOS3000 SIP REGISTER message","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-register-message\/"},"7221":{"name":"VOS3000 SIP registration best practices","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-registration-best-practices\/"},"7206":{"name":"VOS3000 SIP registration configuration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-registration-configuration\/"},"7200":{"name":"VOS3000 SIP registration interval","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-registration-interval\/"},"6091":{"name":"VOS3000 SIP trunk registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-trunk-registration\/"},"7225":{"name":"VOS3000 SIP trunk stability","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-sip-trunk-stability\/"},"7207":{"name":"VOS3000 softswitch registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-softswitch-registration\/"},"7215":{"name":"VOS3000 SS_ENDPOINT_EXPIRE","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-ss_endpoint_expire\/"},"7212":{"name":"VOS3000 SS_ENDPOINT_REGISTER_RETRY","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-ss_endpoint_register_retry\/"},"7211":{"name":"VOS3000 SS_ENDPOINT_REGISTER_SUSPEND","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-ss_endpoint_register_suspend\/"},"7228":{"name":"VOS3000 SS_SIP_USER_AGENT_PRIVACY","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-ss_sip_user_agent_privacy\/"},"7227":{"name":"VOS3000 SS_SIP_USER_AGENT_SEND_UNREGISTER","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-ss_sip_user_agent_send_unregister\/"},"7199":{"name":"VOS3000 user agent expire","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-user-agent-expire\/"},"7217":{"name":"VOS3000 user agent unregister","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-user-agent-unregister\/"},"7204":{"name":"VOS3000 vendor registration timeout","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-vendor-registration-timeout\/"},"7219":{"name":"VOS3000 VoIP registration timer","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-voip-registration-timer\/"},"7229":{"name":"VOS3000 VoIP softswitch registration","link":"https:\/\/www.vos3000.com\/blog\/tag\/vos3000-voip-softswitch-registration\/"}},"comments_number":"0","wpmagazine_modules_lite_featured_media_urls":{"thumbnail":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-150x150.png",150,150,true],"cvmm-medium":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-300x300.png",300,300,true],"cvmm-medium-plus":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-305x207.png",305,207,true],"cvmm-portrait":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-400x600.png",400,600,true],"cvmm-medium-square":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-600x600.png",600,600,true],"cvmm-large":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-1024x1024.png",1024,1024,true],"cvmm-small":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters-130x95.png",130,95,true],"full":["https:\/\/www.vos3000.com\/blog\/wp-content\/uploads\/2026\/04\/VOS3000-SIP-Resend-Interval-VOS3000-SIP-INVITE-Timeout-VOS3000-SIP-Call-Progress-Timeout-VOS3000-SIP-Outbound-Registration-Parameters.png",1536,1024,false]},"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/posts\/1300","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/comments?post=1300"}],"version-history":[{"count":1,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/posts\/1300\/revisions"}],"predecessor-version":[{"id":1305,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/posts\/1300\/revisions\/1305"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/media\/1297"}],"wp:attachment":[{"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/media?parent=1300"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/categories?post=1300"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vos3000.com\/blog\/wp-json\/wp\/v2\/tags?post=1300"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}