1. U

    Socket hangs in recv randomly

    Hi, I have set up a network with a Linux host communicating over TCP/IP with a standard Windows computer. There is a strange behavior occurring sporadically and maybe you have an idea where this might come from. On Linux side there has been a standard TCP socket created which listens for an...
  2. T

    Establishing a TCP connection with Oracle Linux (Red Hat based)

    Hello everyone, I have been struggling to find someone to build a Server for our Video IoT application, so I figured the best way to go about this is to have a shot at taking one step at a time. I understand how the device protocol works, but the struggle is to establish a TCP Connection...
  3. I

    How to create Virtual COM connection on Linux (using TCP)?

    So, I have a Server and a Host. Server machine runs on Windows 7. It has program, that creates some data and sends it to port 1001 using ser2net util. The host is running Linux (Debian 10). It has a program, that runs in Wine. The program must receive data from Server. So, I need to create a...
  4. M

    How to calculate TCP socket memory usage?

    Hi everyone, I am running a Debian GNU/Linux 9.5 (stretch) with kernel: 4.9.0-7-amd64. I am trying to figure out TCP sockets memory usage, but with my calculations I seem to be missing something. According to the following outputs /proc/net/sockstat: sockets: used 779 TCP: inuse 23 orphan 0...
  5. S

    How to extract the TCP header of Incoming and Outgoing Packets using sk_buff? How can we create an LKM for the same?

    I want to extract the TCP header and print the Header details of both incoming as well as outgoing packets but I need to hook that module in the Linux Kernel. That is I need to create an LKM for the same.
  6. D

    Question related to TCP/IP buffering in linux

    I have been trying very hard to find about buffers used in TCP/IP as part of packet transfer in linux. More i read, more i get confused. Below given are questions i have. Can someone help me figure it out? 1)Is the driver queue which is implemented as a ring buffer with descriptors pointing to...
  7. L

    TCP performance for OpenVPN vs delay

    I have got some issue in TCP performance depended on delay. My lab schema: CPE --- (p1) Router (p2) --- Server The CPE connects to the Server by OpenVPN using TCP. I know about TCP-over-TCP but TCP proto is mandatory! Next I do series of network benchmarks through the OpenVPN tunnel. Series...
  8. J

    Router only supports IPv6 port forward but users need IPv4

    Hello there, I currently have a TCP-Server on my local machine. I got an IPv4 and an IPv6 address on this Machine. But my Router only supports IPv6 Port forwarding. I tried that but 99% of the users couldnt connect because they only got IPv4 and the Server is IPv6. I tried "serveo" and "ngrok"...
  9. N

    Open TCP session

    I am getting the relatively high number of open TCP session, can anyone please help me understand how can I increase the limit and is it safe to increase it, depending on server resources. Total: 1079 (kernel 1593) TCP: 40140 (estab 283, closed 39387, orphaned 0, synrecv 0, timewait...
  10. J

    RST hijacking correct ack number

    For learning purpose, I'm trying to RST hijack my current session : 22:29:20.185032 IP > Flags [ S ], seq 2173271328, win 29200, options [mss 1460,sackOK,TS val 3615590 ecr 0,nop,wscale 7], length 0 22:29:20.185090 IP >