![]() ![]() Do a reverse name lookup on the IP addresses if you are unsure what they are about. That should point you toward what ports WeChat uses to communicate with its central servers. WinMerge is fairly competent, free, and open source, although there certainly are others out there, both gratis and paid.) (You'll likely need to grab a diff tool from somewhere else, however. Again, note that Windows' implementation of netstat may be somewhat different in details, but it allows you to do essentially the same thing. The output will tell you the source and destination IP address and port number for anything where the status has changed during the sleep period. ![]() You'd adjust the delay time so that you have time to tell WeChat to connect note that a longer delay will give more false positives in the diff output. In our case, the commands are identical except the second one first calls sleep 10 to give a ten-second delay. What this does is execute the two commands given, and show the difference between their outputs (the outputs are taken as the respective inputs to the diff tool the -u0 basically says do not print any context, because the context provides no useful information in our case). On Linux, you can do that in a single command with a little bit of shell magic: $ diff -u0 <(netstat -an -A inet) <(sleep 10 netstat -an -A inet) The exact syntax varies, but on Linux (Windows is similar but probably not identical), you'd start with something like netstat -an -A inet which gives you a list of basically everything related to IPv4 without doing host name lookups. Such a connections list can be obtained through the netstat utility. By comparing them, we should be able to identify which ports are used by the application we are interested in. The first step would be to take two dumps of the set of open connections: once without WeChat connected, and once with. This works best for TCP, but certainly shouldn't be impossible to generalize to UDP. Other types of applications that communicate over the Internet has the same need, but if it's only a very brief burst-type connection or even datagram transmission it can be difficult to catch, necessiting other techniques to identify the details (for example, network monitoring or firewall logging). If you are able to block that, the application should be unable to connect, and you have achieved your objective. Most applications that have some form of persistent monitoring (as instant messaging applications tend to) will need to connect to some sort of central server or messaging hub initially. We can likely find that out for ourselves, and in the process, have a way to solve the problem generally. TCP vs UDP - TCP: reliable, ordered, heavyweight, streaming UDP - unreliable, not ordered, lightweight, datagrams.It is usually possible to, in a general manner, find out what ports (relatively "well-behaved") applications use to communicate, so we don't necessarily need to know ahead of time what ports WeChat specifically uses. the Domain Name System (DNS), the Routing Information Protocol (RIP), the Dynamic Host Configuration Protocol (DHCP), the Simple Network Management Protocol (SNMP). ![]() UDP (User Datagram Protocol) is a minimal message-oriented Transport Layer protocol (protocol is documented in IETF RFC 768).Īpplication examples that often use UDP: voice over IP (VoIP), streaming media and real-time multiplayer games. UDP on port 334 thinks that error checking and correction is not necessary or performed in the application, avoiding the overhead of such processing at the network interface level. UDP on port 334 provides an unreliable service and datagrams may arrive duplicated, out of order, or missing without notice. UDP port 334 would not have guaranteed communication as TCP. Guaranteed communication over TCP port 334 is the main difference between TCP and UDP. Only when a connection is set up user's data can be sent bi-directionally over the connection.Īttention! TCP guarantees delivery of data packets on port 334 in the same order in which they were sent. TCP is a connection-oriented protocol, it requires handshaking to set up end-to-end communications. TCP is one of the main protocols in TCP/IP networks. TCP port 334 uses the Transmission Control Protocol. ![]()
0 Comments
Leave a Reply. |