diff --git a/trunk/doc/CHANGELOG.md b/trunk/doc/CHANGELOG.md
index 94d188e02..96514037c 100644
--- a/trunk/doc/CHANGELOG.md
+++ b/trunk/doc/CHANGELOG.md
@@ -7,6 +7,7 @@ The changelog for SRS.
 <a name="v6-changes"></a>
 
 ## SRS 6.0 Changelog
+* v6.0, 2023-10-17, Merge [#3837](https://github.com/ossrs/srs/pull/3837): Support set the ice-ufrag and ice-pwd for connectivity check. v6.0.91 (#3837)
 * v6.0, 2023-10-17, Merge [#3758](https://github.com/ossrs/srs/pull/3758): Refine docker detect mechenism. v6.0.90 (#3758)
 * v6.0, 2023-10-11, Merge [#3827](https://github.com/ossrs/srs/pull/3827): Fix bug for upgrading to OpenSSL 3.0. v6.0.89 (#3827)
 * v6.0, 2023-10-10, Merge [#3825](https://github.com/ossrs/srs/pull/3825): SRT: Fix the missing config mss. v6.0.88 (#3825)
@@ -102,6 +103,7 @@ The changelog for SRS.
 <a name="v5-changes"></a>
 
 ## SRS 5.0 Changelog
+* v5.0, 2023-10-17, Merge [#3837](https://github.com/ossrs/srs/pull/3837): Support set the ice-ufrag and ice-pwd for connectivity check. v5.0.191 (#3837)
 * v5.0, 2023-10-17, Merge [#3758](https://github.com/ossrs/srs/pull/3758): Refine docker detect mechenism. v5.0.190 (#3758)
 * v5.0, 2023-10-11, Merge [#3827](https://github.com/ossrs/srs/pull/3827): Fix bug for upgrading to OpenSSL 3.0. v5.0.189 (#3827)
 * v5.0, 2023-10-10, Merge [#3825](https://github.com/ossrs/srs/pull/3825): SRT: Fix the missing config mss. v5.0.188 (#3825)
diff --git a/trunk/src/app/srs_app_rtc_api.cpp b/trunk/src/app/srs_app_rtc_api.cpp
index b5b0080f9..f0ec34469 100644
--- a/trunk/src/app/srs_app_rtc_api.cpp
+++ b/trunk/src/app/srs_app_rtc_api.cpp
@@ -20,6 +20,14 @@
 #include <deque>
 using namespace std;
 
+// To limit the ICE ufrag/username to avoid unknown issue.
+#define SRS_ICE_UFRAG_MIN 4
+#define SRS_ICE_UFRAG_MAX 32
+// STUN/ICE pwd should not be too short, browser will fail with error.
+#define SRS_ICE_PWD_MIN 22
+// To limit user to use too long password, to cause unknown issue.
+#define SRS_ICE_PWD_MAX 32
+
 SrsGoApiRtcPlay::SrsGoApiRtcPlay(SrsRtcServer* server)
 {
     server_ = server;
@@ -691,6 +699,15 @@ srs_error_t SrsGoApiRtcWhip::do_serve_http(ISrsHttpResponseWriter* w, ISrsHttpMe
     ruc->req_->stream = stream.empty() ? "livestream" : stream;
     ruc->req_->param = r->query();
 
+    ruc->req_->ice_ufrag_ = r->query_get("ice-ufrag");
+    ruc->req_->ice_pwd_ = r->query_get("ice-pwd");
+    if (!ruc->req_->ice_ufrag_.empty() && (ruc->req_->ice_ufrag_.length() < SRS_ICE_UFRAG_MIN || ruc->req_->ice_ufrag_.length() > SRS_ICE_UFRAG_MAX)) {
+        return srs_error_new(ERROR_RTC_INVALID_ICE, "Invalid ice-ufrag %s", ruc->req_->ice_ufrag_.c_str());
+    }
+    if (!ruc->req_->ice_pwd_.empty() && (ruc->req_->ice_pwd_.length() < SRS_ICE_PWD_MIN || ruc->req_->ice_pwd_.length() > SRS_ICE_PWD_MAX)) {
+        return srs_error_new(ERROR_RTC_INVALID_ICE, "Invalid ice-pwd %s", ruc->req_->ice_pwd_.c_str());
+    }
+
     // discovery vhost, resolve the vhost from config
     SrsConfDirective* parsed_vhost = _srs_config->get_vhost(ruc->req_->vhost);
     if (parsed_vhost) {
@@ -701,9 +718,10 @@ srs_error_t SrsGoApiRtcWhip::do_serve_http(ISrsHttpResponseWriter* w, ISrsHttpMe
     string srtp = r->query_get("encrypt");
     string dtls = r->query_get("dtls");
 
-    srs_trace("RTC whip %s %s, clientip=%s, app=%s, stream=%s, offer=%dB, eip=%s, codec=%s, srtp=%s, dtls=%s, param=%s",
+    srs_trace("RTC whip %s %s, clientip=%s, app=%s, stream=%s, offer=%dB, eip=%s, codec=%s, srtp=%s, dtls=%s, ufrag=%s, pwd=%s, param=%s",
         action.c_str(), ruc->req_->get_stream_url().c_str(), clientip.c_str(), ruc->req_->app.c_str(), ruc->req_->stream.c_str(),
-        remote_sdp_str.length(), eip.c_str(), codec.c_str(), srtp.c_str(), dtls.c_str(), ruc->req_->param.c_str()
+        remote_sdp_str.length(), eip.c_str(), codec.c_str(), srtp.c_str(), dtls.c_str(), ruc->req_->ice_ufrag_.c_str(),
+        ruc->req_->ice_pwd_.c_str(), ruc->req_->param.c_str()
     );
 
     ruc->eip_ = eip;
diff --git a/trunk/src/app/srs_app_rtc_server.cpp b/trunk/src/app/srs_app_rtc_server.cpp
index c870e956c..24fe29dd4 100644
--- a/trunk/src/app/srs_app_rtc_server.cpp
+++ b/trunk/src/app/srs_app_rtc_server.cpp
@@ -543,17 +543,18 @@ srs_error_t SrsRtcServer::do_create_session(SrsRtcUserConfig* ruc, SrsSdp& local
     // All tracks default as inactive, so we must enable them.
     session->set_all_tracks_status(req->get_stream_url(), ruc->publish_, true);
 
-    std::string local_pwd = srs_random_str(32);
-    std::string local_ufrag = "";
+    std::string local_pwd = ruc->req_->ice_pwd_.empty() ? srs_random_str(32) : ruc->req_->ice_pwd_;
+    std::string local_ufrag = ruc->req_->ice_ufrag_.empty() ? srs_random_str(8) : ruc->req_->ice_ufrag_;
     // TODO: FIXME: Rename for a better name, it's not an username.
     std::string username = "";
     while (true) {
-        local_ufrag = srs_random_str(8);
-
         username = local_ufrag + ":" + ruc->remote_sdp_.get_ice_ufrag();
         if (!_srs_rtc_manager->find_by_name(username)) {
             break;
         }
+
+        // Username conflict, regenerate a new one.
+        local_ufrag = srs_random_str(8);
     }
 
     local_sdp.set_ice_ufrag(local_ufrag);
diff --git a/trunk/src/core/srs_core_version5.hpp b/trunk/src/core/srs_core_version5.hpp
index d6d5b7803..3c20b4dff 100644
--- a/trunk/src/core/srs_core_version5.hpp
+++ b/trunk/src/core/srs_core_version5.hpp
@@ -9,6 +9,6 @@
 
 #define VERSION_MAJOR       5
 #define VERSION_MINOR       0
-#define VERSION_REVISION    190
+#define VERSION_REVISION    191
 
 #endif
diff --git a/trunk/src/core/srs_core_version6.hpp b/trunk/src/core/srs_core_version6.hpp
index 033e1007b..4898158fe 100644
--- a/trunk/src/core/srs_core_version6.hpp
+++ b/trunk/src/core/srs_core_version6.hpp
@@ -9,6 +9,6 @@
 
 #define VERSION_MAJOR       6
 #define VERSION_MINOR       0
-#define VERSION_REVISION    90
+#define VERSION_REVISION    91
 
 #endif
diff --git a/trunk/src/kernel/srs_kernel_error.hpp b/trunk/src/kernel/srs_kernel_error.hpp
index 64091c983..c1f2a9bf5 100644
--- a/trunk/src/kernel/srs_kernel_error.hpp
+++ b/trunk/src/kernel/srs_kernel_error.hpp
@@ -374,7 +374,8 @@
     XX(ERROR_RTC_TCP_PACKET                , 5033, "RtcTcpStun", "RTC TCP first packet must be STUN") \
     XX(ERROR_RTC_TCP_STUN                  , 5034, "RtcTcpSession", "RTC TCP packet is invalid for session not found") \
     XX(ERROR_RTC_TCP_UNIQUE                , 5035, "RtcUnique", "RTC only support one UDP or TCP network") \
-    XX(ERROR_RTC_INVALID_SESSION           , 5036, "RtcInvalidSession", "Invalid request for no RTC session matched")
+    XX(ERROR_RTC_INVALID_SESSION           , 5036, "RtcInvalidSession", "Invalid request for no RTC session matched") \
+    XX(ERROR_RTC_INVALID_ICE               , 5037, "RtcInvalidIce", "Invalid ICE ufrag or pwd")
 
 /**************************************************/
 /* SRT protocol error. */
diff --git a/trunk/src/protocol/srs_protocol_rtmp_stack.hpp b/trunk/src/protocol/srs_protocol_rtmp_stack.hpp
index f171cb4e2..b628d2e12 100644
--- a/trunk/src/protocol/srs_protocol_rtmp_stack.hpp
+++ b/trunk/src/protocol/srs_protocol_rtmp_stack.hpp
@@ -424,6 +424,10 @@ public:
     std::string param;
     // The stream in play/publish
     std::string stream;
+    // User specify the ice-ufrag, the username of ice, for test only.
+    std::string ice_ufrag_;
+    // User specify the ice-pwd, the password of ice, for test only.
+    std::string ice_pwd_;
     // For play live stream,
     // used to specified the stop when exceed the duration.
     // in srs_utime_t.