Questions tagged [networking]
For most programming questions use [network-programming] tag. Non-programming networking questions are off topic and should be asked on Network Engineering, Super User or Server Fault instead. This tag is only appropriate for questions concerning unique networking needs in support of software development.
networking
38,316
questions
3295
votes
34
answers
5.4m
views
How do I find out which process is listening on a TCP or UDP port on Windows? [closed]
How do I find out which process is listening on a TCP or UDP port on Windows?
1131
votes
37
answers
531k
views
What is the difference between a port and a socket?
This was a question raised by one of the Software Engineers in my organisation. I'm interested in the broadest definition.
879
votes
37
answers
1.6m
views
How can I connect to Android with ADB over TCP? [closed]
I am attempting to debug an application on a Motorola Droid, but I am having some difficulty connecting to the device via USB. My development server is a Windows 7 64-bit VM running in Hyper-V, and so ...
745
votes
14
answers
965k
views
What is the quickest way to HTTP GET in Python?
What is the quickest way to HTTP GET in Python if I know the content will be a string? I am searching the documentation for a quick one-liner like:
contents = url.get("http://example.com/foo/bar")
...
730
votes
50
answers
986k
views
Finding local IP addresses using Python's stdlib
How can I find local IP addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?
597
votes
10
answers
265k
views
Comparison of Android networking libraries: OkHTTP, Retrofit, and Volley [closed]
Two-part question from an iOS developer learning Android, working on an Android project that will make a variety of requests from JSON to image to streaming download of audio and video:
On iOS I have ...
588
votes
21
answers
358k
views
Is it possible to disable the network in iOS Simulator?
I am trying to debug some inconsistent behaviour I am seeing in an application that gets its primary data from the Internet. I don't see the issues in the simulator, just on the device, so I'd like ...
396
votes
22
answers
224k
views
Artificially create a connection timeout error
I've had a bug in our software that occurs when I receive a connection timeout. These errors are very rare (usually when my connection gets dropped by our internal network). How can I generate this ...
388
votes
28
answers
770k
views
Get local IP address
In the internet there are several places that show you how to get an IP address. And a lot of them look like this example:
String strHostName = string.Empty;
// Getting Ip address of local machine...
...
361
votes
18
answers
1.6m
views
Command line for looking at specific port
Is there a way to examine the status of a specific port from the Windows command line? I know I can use netstat to examine all ports but netstat is slow and looking at a specific port probably isn't.
352
votes
3
answers
1.6m
views
How to get a list of all valid IP addresses in a local network? [closed]
Is there a way to get a list of all valid IP addresses in a local network?
I mean all IP addresses that each user is using in the network.
344
votes
16
answers
729k
views
How do I get Flask to run on port 80?
I have a Flask server running through port 5000, and it's fine. I can access it at http://example.com:5000
But is it possible to simply access it at http://example.com? I'm assuming that means I have ...
342
votes
24
answers
246k
views
When is it appropriate to use UDP instead of TCP? [closed]
Since TCP guarantees packet delivery and thus can be considered "reliable", whereas UDP doesn't guarantee anything and packets can be lost. What would be the advantage of transmitting data using UDP ...
338
votes
13
answers
67k
views
Best architectural approaches for building iOS networking applications (REST clients) [closed]
I'm an iOS developer with some experience and this question is really interesting to me. I saw a lot of different resources and materials on this topic, but nevertheless I'm still confused. What is ...
333
votes
8
answers
197k
views
What is P99 latency?
What does P99 latency represent? I keep hearing about this in discussions about an application's performance but couldn't find a resource online that would talk about this.
332
votes
5
answers
367k
views
What is the difference between active and passive FTP?
Can someone tell me what is the difference between active and passive FTP?
Which one is preferable?
312
votes
5
answers
160k
views
What do pty and tty mean?
I noticed many mentions of pty and tty in some open source projects, could someone tell me what do they mean and what is the difference between them?
307
votes
15
answers
530k
views
Capturing mobile phone traffic on Wireshark
How can I capture mobile phone traffic on Wireshark?
298
votes
7
answers
299k
views
Network usage top/htop on Linux [closed]
Is there a htop/top on Linux where I get to sort processes by network usage?
276
votes
20
answers
522k
views
Android check internet connection [duplicate]
I want to create an app that uses the internet and I'm trying to create a function that checks if a connection is available and if it isn't, go to an activity that has a retry button and an ...
270
votes
22
answers
976k
views
How do I resolve the "java.net.BindException: Address already in use: JVM_Bind" error?
In Eclipse, I got this error:
run:
[java] Error creating the server socket.
[java] Oct 04, 2012 5:31:38 PM cascadas.ace.AceFactory bootstrap
[java] SEVERE: Failed to create world : ...
267
votes
5
answers
601k
views
Increasing the maximum number of TCP/IP connections in Linux
I am programming a server and it seems like my number of connections is being limited since my bandwidth isn't being saturated even when I've set the number of connections to "unlimited".
How can I ...
262
votes
16
answers
165k
views
Network tools that simulate slow network connection [closed]
I would like to visually evaluate web pages response time for several Internet connections types (DSL, Cable, T1, dial-up etc.) while my browser and web server are on the same LAN or even on the same ...
258
votes
11
answers
290k
views
Forward host port to docker container
Is it possible to have a Docker container access ports opened by the host? Concretely I have MongoDB and RabbitMQ running on the host and I'd like to run a process in a Docker container to listen to ...
254
votes
9
answers
318k
views
close vs shutdown socket?
In C, I understood that if we close a socket, it means the socket will be destroyed and can be re-used later.
How about shutdown? The description said it closes half of a duplex connection to that ...
249
votes
18
answers
1.4m
views
java.net.ConnectException: Connection refused
I'm trying to implement a TCP connection, everything works fine from the server's side but when I run the client program (from client computer) I get the following error:
java.net.ConnectException: ...
249
votes
21
answers
959k
views
An existing connection was forcibly closed by the remote host
I am working with a commercial application which is throwing a SocketException with the message,
An existing connection was forcibly closed by the remote host
This happens with a socket connection ...
246
votes
13
answers
359k
views
What is the largest Safe UDP Packet Size on the Internet
I've read a number of articles about UDP packet sizes but have been unable to come to a conclusion on whats correct.
A number of services restrict the largest UDP packet to 512 bytes (like dns)
...
239
votes
18
answers
1.1m
views
How to close TCP and UDP ports via windows command line
Does somebody knows how to close a TCP or UDP socket for a single connection via windows command line?
Googling about this, I saw some people asking the same thing. But the answers looked like a ...
233
votes
10
answers
445k
views
Maximum packet size for a TCP connection
What is the maximum packet size for a TCP connection or how can I get the maximum packet size?
228
votes
4
answers
334k
views
Access HTTP response as string in Go
I'd like to parse the response of a web request, but I'm getting trouble accessing it as string.
func main() {
resp, err := http.Get("http://google.hu/")
if err != nil {
// handle ...
226
votes
5
answers
179k
views
What is the difference between 127.0.0.1 and localhost
Assuming the following is defined in .../hosts:
127.0.0.1 localhost
What, if any, are the actual differences between using 127.0.0.1 and localhost as the server name, especially when hitting ...
226
votes
14
answers
59k
views
A clean, lightweight alternative to Python's twisted? [closed]
A (long) while ago I wrote a web-spider that I multithreaded to enable concurrent requests to occur at the same time. That was in my Python youth, in the days before I knew about the GIL and the ...
225
votes
14
answers
276k
views
UDP vs TCP, how much faster is it? [closed]
For general protocol message exchange, which can tolerate some packet loss. How much more efficient is UDP over TCP?
224
votes
13
answers
370k
views
How to provide user name and password when connecting to a network share
When connecting to a network share for which the current user (in my case, a network enabled service user) has no rights, name and password have to be provided.
I know how to do this with Win32 ...
224
votes
19
answers
228k
views
How to find an available port?
I want to start a server which listen to a port. I can specify port explicitly and it works. But I would like to find a port in an automatic way. In this respect I have two questions.
In which range ...
220
votes
16
answers
787k
views
ssh: Could not resolve hostname [hostname]: nodename nor servname provided, or not known [closed]
I am trying to set up a VPN with a Raspberry Pi, and the first step is gaining the ability to ssh into the device from outside my local network. For whatever reason, this is proving to be impossible ...
216
votes
11
answers
56k
views
Why is SCTP not much used/known
I recently checked out the book "UNIX Network Programming, Vol. 1" by Richards Stevens and I found that there is a third transport layer standard besides TCP and UDP: SCTP.
Summary: SCTP is a ...
215
votes
17
answers
163k
views
Simulating Slow Internet Connection [closed]
I know this is kind of an odd question. Since I usually develop applications based on the "assumption" that all users have a slow internet connection. But, does anybody think that there is a way to ...
213
votes
7
answers
66k
views
protobuf vs gRPC
I try to understand protobuf and gRPC and how I can use both. Could you help me understand the following:
Considering the OSI model what is where, for example is Protobuf at layer 4?
Thinking through ...
209
votes
11
answers
459k
views
Freeing up a TCP/IP port? [closed]
netstat -tulnap
shows me what ports are in use. How to free up a port in Linux?
197
votes
15
answers
172k
views
Detect network connection type on Android
How do you detect the network connection type on Android?
Is it through ConnectivityManager.getActiveNetworkInfo().getType(), and is the answer limited to Wifi and mobile?
186
votes
11
answers
342k
views
How to validate IP address in Python? [duplicate]
What's the best way to validate that an IP entered by the user is valid? It comes in as a string.
185
votes
17
answers
1.2m
views
java.net.SocketException: Connection reset
I am getting the following error trying to read from a socket. I'm doing a readInt() on that InputStream, and I am getting this error. Perusing the documentation suggests that the client part of the ...
183
votes
5
answers
732k
views
ping response "Request timed out." vs "Destination Host unreachable"
When I ping an IP address, what is the difference between Request timed out and Destination host unreachable returned from the command?
182
votes
8
answers
158k
views
How to get access to webpack-dev-server from devices in local network?
There is some webpack dev server config (it's part of the whole config):
config.devServer = {
contentBase: './' + (options.publicFolder ? options.publicFolder : 'public'),
stats: {
modules: ...
182
votes
28
answers
146k
views
ConnectivityManager getNetworkInfo(int) deprecated
Using compileSdkVersion 23, however trying to support as far back as 9.
getNetworkInfo(int) was deprecated in 23. The suggestion was to use getAllNetworks() and getNetworkInfo(Network) instead. ...
177
votes
22
answers
274k
views
How can I see if there's an available and active network connection in Python?
I want to see if I can access an online API, but for that, I need to have Internet access.
How can I see if there's a connection available and active using Python?
172
votes
4
answers
210k
views
Event for Handling the Focus of the EditText
Can anyone suggest to me any event related to the focus of the EditText?
My application contains an EditText, which accepts a URL in it.
Now my problem is that, that after the user will enter the URL ...
168
votes
12
answers
707k
views
What causes a TCP/IP reset (RST) flag to be sent?
I'm trying to figure out why my app's TCP/IP connection keeps hiccuping every 10 minutes (exactly, within 1-2 seconds). I ran Wireshark and discovered that after 10 minutes of inactivity the other ...