The part after the slash is how many subnet mask bits to use. Since the use of classless routing you use slash instead of saying class A or B whatever. Example: 192.168.1.1/24 is 192.168.1.1 255.255.255.0 255.255.255.0 is using 24 of the 32 bits to create the subnet. in binary it looks like this: 11111111.11111111.11111111.00000000 so … Read more
You, my friend, are confusing the functionality of two different layers. TCP is connection oriented in the sense that there’s a connection establishment, between the two ends where they may negotiate different things like congestion-control mechanism among other things. The transport layer protocols’ general purpose is to provide process-to-process delivery meaning that it doesn’t know … Read more
I suppose that your problem is that you are running server somewhere in local network, so you get your IP in that network. However when you are trying to use online service that discovers your IP address your IP is the IP of your service provider’s router or something like this. Using request.getRemoteAddr() is correct. … Read more
If you need 200ms for each of the 65536 ports (in the worst case, a firewall is blocking everything, thus making you hit your timeout for every single port), the maths is pretty simple: you need 13k seconds, or about 3 hours and a half. You have 2 (non-exclusive) options to make it faster: reduce … Read more
The domain company that you talked to may have done a poor job of explaining how domains work. Domain names don’t refer to specific ports. They just refer to IP addresses. The client can look up a hostname to get the IP address which the client should connect to, but the client has to figure … Read more
If you’re a normal user (i.e., not ‘root’) ifconfig isn’t in your path, but it’s the command you want. More specifically: /usr/sbin/ifconfig -a
I found the solution for this issue: json-server –host 192.168.1.XXX my_file.json Using this command, server is deployed on my local IP, and Windows asks for a firewall exception. Another solution is to switch to .NET server – another free simple fake server where I can setup local IP as endpoint. All it needs to: install … Read more
Ruby has already the needed Regex in the standard library. Checkout resolv. require “resolv” “192.168.1.1” =~ Resolv::IPv4::Regex ? true : false #=> true “192.168.1.500” =~ Resolv::IPv4::Regex ? true : false #=> false “ff02::1” =~ Resolv::IPv6::Regex ? true : false #=> true “ff02::1::1” =~ Resolv::IPv6::Regex ? true : false #=> false If you like it the … Read more
String ip; try { Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces(); while (interfaces.hasMoreElements()) { NetworkInterface iface = interfaces.nextElement(); // filters out 127.0.0.1 and inactive interfaces if (iface.isLoopback() || !iface.isUp()) continue; Enumeration<InetAddress> addresses = iface.getInetAddresses(); while(addresses.hasMoreElements()) { InetAddress addr = addresses.nextElement(); ip = addr.getHostAddress(); System.out.println(iface.getDisplayName() + ” ” + ip); } } } catch (SocketException e) { throw new … Read more