when connect to some router , roscore run slowly

rosmaster log :

[rosmaster.main][INFO] 2000-01-01 08:23:10,730: initialization complete, waiting for shutdown
[rosmaster.main][INFO] 2000-01-01 08:23:10,731: Starting ROS Master Node
[xmlrpc][INFO] 2000-01-01 08:23:10,734: XML-RPC server binding to 127.0.0.1:11311
[xmlrpc][INFO] 2000-01-01 08:23:10,736: Started XML-RPC server [http://localhost:11311/]
[rosmaster.master][INFO] 2000-01-01 08:23:10,737: Master initialized: port[11311], uri[http://localhost:11311/]
[xmlrpc][INFO] 2000-01-01 08:23:10,737: xml rpc node: starting XML-RPC server
[rosmaster.master][INFO] 2000-01-01 08:23:29,094: +PARAM [/run_id] by /roslaunch
[rosmaster.master][INFO] 2000-01-01 08:23:29,285: +PARAM [/roslaunch/uris/host_localhost__40891] by /roslaunch
[rosmaster.master][INFO] 2000-01-01 08:23:57,747: +SERVICE [/rosout/get_loggers] /rosout http://localhost:37711/
[rosmaster.master][INFO] 2000-01-01 08:24:00,013: +PARAM [/rosversion] by /roslaunch
[rosmaster.master][INFO] 2000-01-01 08:24:00,014: +PARAM [/rosdistro] by /roslaunch
[rosmaster.master][INFO] 2000-01-01 08:24:02,970: +SERVICE [/rosout/set_logger_level] /rosout http://localhost:37711/
[rosmaster.master][INFO] 2000-01-01 08:24:14,515: +PUB [/rosout_agg] /rosout http://localhost:37711/