diff --git a/trunk/research/librtmp/srs_detect_rtmp.c b/trunk/research/librtmp/srs_detect_rtmp.c
index 853c2a797..c97b8d21e 100644
--- a/trunk/research/librtmp/srs_detect_rtmp.c
+++ b/trunk/research/librtmp/srs_detect_rtmp.c
@@ -33,35 +33,77 @@ int main(int argc, char** argv)
 {
     srs_rtmp_t rtmp;
     
+    // time
+    int64_t time_startup = srs_get_time_ms();
+    int64_t time_dns_resolve = 0;
+    int64_t time_socket_connect = 0;
+    int64_t time_play_stream = 0;
+    int64_t time_first_packet = 0;
+    int64_t time_cleanup = 0;
+    // delay = actual - expect time when quit.
+    int delay = 0;
+    
     // packet data
     int type, size;
     u_int32_t timestamp = 0;
     char* data;
     
-    if (argc <= 1) {
+    // user options
+    const char* rtmp_url = NULL;
+    int duration = 0;
+    int timeout = 0;
+    
+    if (argc <= 3) {
         printf("detect stream on RTMP server\n"
-            "Usage: %s <rtmp_url>\n"
+            "Usage: %s <rtmp_url> <duration> <timeout>\n"
             "   rtmp_url     RTMP stream url to play\n"
+            "   duration     how long to play, in seconds, stream time.\n"
+            "   timeout      how long to timeout, in seconds, system time.\n"
             "For example:\n"
-            "   %s rtmp://127.0.0.1:1935/live/livestream\n",
+            "   %s rtmp://127.0.0.1:1935/live/livestream 3 10\n",
             argv[0]);
         int ret = 1;
         exit(ret);
         return ret;
     }
     
-    rtmp = srs_rtmp_create(argv[1]);
+    rtmp_url = argv[1];
+    duration = atoi(argv[2]);
+    timeout = atoi(argv[3]);
     
     printf("detect rtmp stream\n");
     printf("srs(simple-rtmp-server) client librtmp library.\n");
     printf("version: %d.%d.%d\n", srs_version_major(), srs_version_minor(), srs_version_revision());
-    printf("rtmp url: %s\n", rtmp);
+    printf("rtmp url: %s\n", rtmp_url);
+    printf("duration: %ds, timeout:%ds\n", duration, timeout);
+    
+    if (duration <= 0 || timeout <= 0) {
+        printf("duration and timeout must be positive.\n");
+        exit(1);
+        return 1;
+    }
+    
+    rtmp = srs_rtmp_create(rtmp_url);
+    
+    if (__srs_dns_resolve(rtmp) != 0) {
+        printf("dns resolve failed.\n");
+        goto rtmp_destroy;
+    }
+    printf("dns resolve success\n");
+    time_dns_resolve = srs_get_time_ms();
+    
+    if (__srs_connect_server(rtmp) != 0) {
+        printf("socket connect failed.\n");
+        goto rtmp_destroy;
+    }
+    printf("socket connect success\n");
+    time_socket_connect = srs_get_time_ms();
     
-    if (srs_simple_handshake(rtmp) != 0) {
-        printf("simple handshake failed.\n");
+    if (__srs_do_simple_handshake(rtmp) != 0) {
+        printf("do simple handshake failed.\n");
         goto rtmp_destroy;
     }
-    printf("simple handshake success\n");
+    printf("do simple handshake success\n");
     
     if (srs_connect_app(rtmp) != 0) {
         printf("connect vhost/app failed.\n");
@@ -74,6 +116,7 @@ int main(int argc, char** argv)
         goto rtmp_destroy;
     }
     printf("play stream success\n");
+    time_play_stream = srs_get_time_ms();
     
     for (;;) {
         if (srs_read_packet(rtmp, &type, &timestamp, &data, &size) != 0) {
@@ -81,11 +124,52 @@ int main(int argc, char** argv)
         }
         printf("got packet: type=%s, time=%d, size=%d\n", srs_type2string(type), timestamp, size);
         
+        if (time_first_packet <= 0) {
+            time_first_packet = srs_get_time_ms();
+        }
+        
         free(data);
+        
+        if (srs_get_time_ms() - time_startup > timeout * 1000) {
+            printf("timeout, terminate.\n");
+            goto rtmp_destroy;
+        }
+        
+        if (timestamp > duration * 1000) {
+            printf("duration exceed, terminate.\n");
+            goto rtmp_destroy;
+        }
     }
     
 rtmp_destroy:
     srs_rtmp_destroy(rtmp);
+    time_cleanup = srs_get_time_ms();
+    
+    // print result to stderr.
+    fprintf(stderr, "{"
+        "\"%s\":%d, " //#1
+        "\"%s\":%d, " // #2
+        "\"%s\":%d, " // #3
+        "\"%s\":%d, " // #4
+        "\"%s\":%d, " // #5
+        "\"%s\":%d, " // #6
+        "\"%s\":%d, " // #7
+        "%s}",
+        // total = dns + tcp_connect + start_play + first_packet + last_packet
+        "total", (int)(time_cleanup - time_startup), //#1
+        "dns", (int)(time_dns_resolve - time_startup), //#2
+        "tcp_connect", (int)(time_socket_connect - time_dns_resolve), //#3
+        "start_play", (int)(time_play_stream - time_socket_connect), //#4
+        "first_packet", (int)(time_first_packet - time_play_stream), //#5
+        "last_packet", (int)(time_cleanup - time_first_packet), //#6
+        // expect = time_cleanup - time_first_packet
+        // actual = timestamp
+        // delay = actual - expect
+        "delay", (int)(timestamp - (time_cleanup - time_first_packet)), //#7
+        // unit in ms.
+        "\"unit\": \"ms\""
+    );
+    printf("\n");
     
     return 0;
 }
diff --git a/trunk/research/librtmp/srs_play.c b/trunk/research/librtmp/srs_play.c
index 9a22908dd..644794477 100644
--- a/trunk/research/librtmp/srs_play.c
+++ b/trunk/research/librtmp/srs_play.c
@@ -55,7 +55,7 @@ int main(int argc, char** argv)
     printf("suck rtmp stream like rtmpdump\n");
     printf("srs(simple-rtmp-server) client librtmp library.\n");
     printf("version: %d.%d.%d\n", srs_version_major(), srs_version_minor(), srs_version_revision());
-    printf("rtmp url: %s\n", rtmp);
+    printf("rtmp url: %s\n", argv[1]);
     
     if (srs_simple_handshake(rtmp) != 0) {
         printf("simple handshake failed.\n");
diff --git a/trunk/src/libs/srs_librtmp.cpp b/trunk/src/libs/srs_librtmp.cpp
index 7acb5cae6..d362b54c0 100644
--- a/trunk/src/libs/srs_librtmp.cpp
+++ b/trunk/src/libs/srs_librtmp.cpp
@@ -57,6 +57,7 @@ struct Context
     std::string url;
     std::string tcUrl;
     std::string host;
+    std::string ip;
     std::string port;
     std::string vhost;
     std::string app;
@@ -77,7 +78,7 @@ struct Context
     }
 };
 
-int srs_librtmp_context_connect(Context* context) 
+int srs_librtmp_context_parse_uri(Context* context) 
 {
     int ret = ERROR_SUCCESS;
     
@@ -123,6 +124,13 @@ int srs_librtmp_context_connect(Context* context)
         }
     }
     
+    return ret;
+}
+
+int srs_librtmp_context_resolve_host(Context* context) 
+{
+    int ret = ERROR_SUCCESS;
+    
     // create socket
     srs_freep(context->skt);
     context->skt = new SimpleSocketStream();
@@ -132,11 +140,24 @@ int srs_librtmp_context_connect(Context* context)
     }
     
     // connect to server:port
-    string server = srs_dns_resolve(context->host);
-    if (server.empty()) {
+    context->ip = srs_dns_resolve(context->host);
+    if (context->ip.empty()) {
         return -1;
     }
-    if ((ret = context->skt->connect(server.c_str(), ::atoi(context->port.c_str()))) != ERROR_SUCCESS) {
+    
+    return ret;
+}
+
+int srs_librtmp_context_connect(Context* context) 
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(context->skt);
+    
+    std::string ip = context->ip;
+    int port = ::atoi(context->port.c_str());
+    
+    if ((ret = context->skt->connect(ip.c_str(), port)) != ERROR_SUCCESS) {
         return ret;
     }
     
@@ -166,14 +187,63 @@ int srs_simple_handshake(srs_rtmp_t rtmp)
 {
     int ret = ERROR_SUCCESS;
     
+    if ((ret = __srs_dns_resolve(rtmp)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    if ((ret = __srs_connect_server(rtmp)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    if ((ret = __srs_do_simple_handshake(rtmp)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int __srs_dns_resolve(srs_rtmp_t rtmp)
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(rtmp != NULL);
+    Context* context = (Context*)rtmp;
+    
+    // parse uri
+    if ((ret = srs_librtmp_context_parse_uri(context)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    // resolve host
+    if ((ret = srs_librtmp_context_resolve_host(context)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int __srs_connect_server(srs_rtmp_t rtmp)
+{
+    int ret = ERROR_SUCCESS;
+    
     srs_assert(rtmp != NULL);
     Context* context = (Context*)rtmp;
     
-    // parse uri, resolve host, connect to server:port
     if ((ret = srs_librtmp_context_connect(context)) != ERROR_SUCCESS) {
         return ret;
     }
     
+    return ret;
+}
+
+int __srs_do_simple_handshake(srs_rtmp_t rtmp)
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(rtmp != NULL);
+    Context* context = (Context*)rtmp;
+    
+    srs_assert(context->skt != NULL);
+    
     // simple handshake
     srs_freep(context->rtmp);
     context->rtmp = new SrsRtmpClient(context->skt);
diff --git a/trunk/src/libs/srs_librtmp.hpp b/trunk/src/libs/srs_librtmp.hpp
index 2563a76c9..c104852eb 100644
--- a/trunk/src/libs/srs_librtmp.hpp
+++ b/trunk/src/libs/srs_librtmp.hpp
@@ -55,7 +55,7 @@ srs_rtmp_t srs_rtmp_create(const char* url);
 void srs_rtmp_destroy(srs_rtmp_t rtmp);
 
 /**
-* handshake with server
+* connect and handshake with server
 * category: publish/play
 * previous: rtmp-create
 * next: connect-app
@@ -65,7 +65,20 @@ void srs_rtmp_destroy(srs_rtmp_t rtmp);
 * simple handshake specifies in rtmp 1.0,
 * not depends on ssl.
 */
+/**
+* srs_simple_handshake equals to invoke:
+*       __srs_dns_resolve()
+*       __srs_connect_server()
+*       __srs_do_simple_handshake()
+* user can use these functions if needed.
+*/
 int srs_simple_handshake(srs_rtmp_t rtmp);
+// parse uri, create socket, resolve host
+int __srs_dns_resolve(srs_rtmp_t rtmp);
+// connect socket to server
+int __srs_connect_server(srs_rtmp_t rtmp);
+// do simple handshake over socket.
+int __srs_do_simple_handshake(srs_rtmp_t rtmp);
 
 /**
 * connect to rtmp vhost/app