369 Test if a port on a remote system is reachable (without telnet) 2013-07-19T16:54:10.383

219 What is port forwarding and what is it used for? 2011-05-16T04:00:37.510

172 What are CLOSE_WAIT and TIME_WAIT states? 2010-08-08T19:23:19.413

139 Finding the process that is using a certain port in Linux 2009-09-17T18:52:03.637

116 Manually closing a port from commandline 2010-04-06T03:39:57.320

61 Why was port 80 chosen as the default HTTP port and 443 as the default HTTPS port? 2015-11-06T08:50:24.050

57 Do web browsers use different outgoing ports for different tabs? 2016-03-20T20:32:03.687

55 PID:4 using Port 80 2011-10-30T01:40:49.907

40 Is there any harm of leaving Ethernet outlet unplugged? 2018-03-19T23:36:06.757

34 No idea what is listening on port 80 in OS X 2013-05-19T17:45:44.840

31 How can I check which ports are busy and which ports are free on my Linux machine? 2011-12-23T12:49:28.583

30 How to find out what is running on localhost port 2014-02-06T22:28:44.237

28 How are source ports determined and how can I force it to use a specific port 2016-08-29T10:01:37.133

25 Utility to open TCP port to listen state 2012-03-07T12:39:18.733

23 Are there good alternative HTTP ports rather than port 80? 2013-06-08T02:25:20.837

21 How to kill a particular tcp connection in windows? 2012-02-01T14:23:06.353

21 Why can I not connect to a reverse SSH tunnel port remotely, even with GatewayPorts enabled? 2014-06-11T17:36:33.970

20 Apache Server on Windows 7 opening up ports? 2010-01-07T04:15:26.470

20 Difference between port mapped and memory mapped access? 2014-01-18T22:08:40.937

20 Should I run my small website in port 80, 8080, or 81? 2014-02-23T17:52:40.583

20 Linux command get unused port 2015-03-04T12:39:14.453

19 802.1X: What EXACTLY is it regarding WPA and EAP? 2012-01-01T01:21:04.307

18 Port 5357 TCP on Windows 7 professional 64 bit? 2009-10-17T23:33:14.577

18 Figure out non standard ssh port 2010-06-15T17:28:50.337

17 How to open TCP port in Ubuntu 10.10? 2010-10-13T07:43:40.157

17 Find out what program runs in the java.exe process 2010-11-18T13:30:40.443

17 Does it matter what UDP port a WOL signal is sent to? 2011-06-10T05:52:27.257

16 How to specify VNC port number with Mac OS X built-in VNC client? 2011-02-14T03:15:59.233

16 Kill what ever is running on port 8080 2013-06-20T00:29:23.077

15 Why is "nc -l xxxx" not opening a port? 2012-07-31T15:47:21.063

15 How to access NodeJS server on LAN? 2013-04-11T18:12:51.453

15 How to block all ports except 80,443 with iptables? 2014-06-17T09:06:40.320

14 How to kill a process by port on MacOS, a la fuser -k 9000/tcp 2012-07-19T15:41:35.483

13 Why does my USB cable have an extra red plug? 2009-11-14T22:58:59.083

13 Netgear router listening on port 32764? 2010-07-22T20:42:51.177

13 Why is System listening on port 8000? 2011-11-22T11:28:40.100

13 how to disable feature that opened port 445 on windows server? 2013-08-08T18:46:00.920

13 Why are USB ports sometimes referred to as serial ports and called COM? 2017-05-06T14:00:12.620

12 Is there a simple way to detect ISP port blocking? 2009-07-22T16:14:44.403

12 How to "restart/repair" an USB port? 2009-12-17T21:45:35.870

12 Why does google chrome need so many ports open? 2012-04-07T01:23:34.753

12 Open port 5672/tcp for access to RabbitMQ on Mac 2012-08-21T10:27:51.280

12 Outgoing VPN PPTP: How to check if TCP port 1723 and GRE protocol port 47 are blocked or not in Windows 7? 2012-09-28T16:29:40.297

12 Determining what process has bound a port (without listening) on Windows 2013-02-26T15:12:30.990

11 How do I find out what service is using a certain port? 2009-08-21T16:41:48.170

11 What port needs to be open for Debian to get updates? 2010-03-16T20:54:58.567

11 What ports are used by an application 2015-05-06T07:07:17.917

10 How do I make Skype not use port 80? 2010-05-13T02:18:15.230

10 What are ports and protocols really? 2011-10-14T02:25:57.227

10 268 Ports Associated with Chrome 2013-03-18T01:16:05.260

10 Multiple processes listening on the same port; how is it possible? 2017-11-10T08:21:36.937

9 Accessing freenode without ports 2010-03-17T11:07:48.217

9 How to discover if a specific address/port is reachable? 2010-04-08T11:34:28.563

9 How to show closed ports in NMap? 2011-03-14T20:58:24.050

9 What is binding this port? 2012-04-27T13:42:09.043

9 Why is port 1111 open, and is it safe to be? 2012-07-19T14:29:25.370

9 How to know which port is busy or free on Windows 7? 2012-07-20T08:09:18.163

9 USB Ports Not Working 2013-12-19T18:22:52.597

9 What can the second LAN port be used for on a NAS? 2014-09-20T15:22:23.730

9 SSH: Troubleshooting "Remote port forwarding failed for listen port" errors 2017-03-31T02:36:42.773

8 How do I determine which application is using port 8080? 2010-05-18T09:13:17.600

8 WWAHost.exe using same port as Apache 2012-10-28T11:11:10.680

8 Why does USB 3.1 only use two of the four available data lines? 2017-05-26T19:45:57.397

7 Will cases with front USB port support USB 3.0? 2010-02-22T12:59:11.183

7 How can I close a port (seen open on netstat)? 2010-07-24T06:27:12.147

7 Is this how ftp works? 2011-02-21T10:39:12.353

7 How can I find out which process is listening on a port on linux? 2011-03-16T09:57:04.530

7 How to find which ports are blocked? 2013-04-18T08:19:30.190

7 Jenkins listens on weird ports 2014-01-13T14:13:00.330

7 How to detect if a network is blocking outgoing ports? 2018-07-03T00:17:14.227

6 What does it mean when a portscan shows a port as "tcpwrapped"? 2009-12-17T04:33:51.773

6 How does seeding in uTorrent work if I don't forward any ports? 2010-01-06T05:25:54.920

6 what port is this 2010-03-11T16:37:49.950

6 Why is there electricity flowing through my VGA and other connectors? 2011-08-17T18:05:48.933

6 Why is this NMAP scan to a remote host showing me no ports open when the ports REALLY are open? 2011-10-19T16:12:25.003

6 How can I map a domain name to an IP address and port? 2012-02-25T23:35:47.323

6 Windows 7 is blocking ports 2012-06-07T16:34:35.740

6 Why are ports 30000 to 60000 needed when browsing the net 2012-09-25T19:41:05.197

6 socket.error: [Errno 10013] Port forbidden access permissions 2013-08-22T22:17:15.427

6 Source Address / Source Port vs Destination Address / Destination Port 2014-01-21T09:42:12.890

6 What is this socket/port/connector on my laptop? 2016-12-25T08:46:37.210

5 Dos and/or Windows versions of Unix SCRIPT command 2009-08-01T20:56:31.033

5 Can I connect a switch to a router? 2010-01-04T03:09:38.867

5 Redirect browser to different host and port 2010-01-08T21:34:13.137

5 How map/forward port under Ubuntu for other machine ? (localhost 555 -> 192.168.0.21:555) 2010-05-02T19:10:23.970

5 So port is not unique by machine at all? 2011-04-06T07:26:36.533

5 What is blocking my ports? 2011-05-18T15:38:24.473

5 Cannot connect to guest OS from host OS 2011-05-24T18:54:29.617

5 (13)Permission denied: make_sock: could not bind to address [::]:80, Mac OS Lion 2011-11-03T07:07:29.663

5 Trying to run Apache, but VMWare Workstation is blocking port 80 2012-04-20T13:07:08.327

5 Localhost not recognized in windows 7 machine 2012-08-09T17:09:23.740

5 Something is using port 80 and I can't figure out what 2012-08-28T04:14:21.173

5 What is the difference between Port and Connector? 2012-10-01T21:01:17.030

5 Minecraft servers - 1 external IP, 2 servers, 2 ports - avoid specifying port in game - SRV record 2013-02-24T18:22:53.933

5 Cannot start WebSite because port 80 is being used by W3SVC.exe 2013-04-14T23:51:46.663

5 How does a server distinguish between multiple requests from same ip address and port? 2016-11-25T13:15:42.597

5 Close port which has no process attached? 2017-06-22T00:03:08.880

4 How can I plug my LPT printer into a motherboard with no parallel port? 2009-11-03T07:54:58.383

4 What is this port on my computer? 2010-03-16T19:55:45.083