Questions tagged [tcp]
TCP stands for Transmission Control Protocol and is one of the core protocols of the Internet Protocol Suite. TCP complements the Internet Protocol (IP), and therefore the entire suite is commonly referred to as TCP/IP.
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What handshakes happen (or need to happen) when I connect my FPGA with Ethernet cable to my home router+modem device in one of its ethernet port? [closed]
I have a FPGA edge device. I want to send and receive ethernet packets to my laptop through the router+modem device at my house. My laptop is connected to the router+modem through the wifi (for ...
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Are there any alternatives to tracert command in cmd/PowerShell that doesn't suffer the request timed out issue?
The cmd tracert <URL> command, quite often, suffers the request timed out issue if the ICMP packets/port are blocked by the routers/ISP's firewall. Now I was wondering if there is any cmd/...
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What ends a TCP stream?
I am using WireShark and went to google.com. I got 23 TCP streams,23 TCP conversations, 23 handshakes right? I know that the TCP streams end with FIN Flag and that TCP segments are encapsulated in the ...
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TCPView (Windows) doesn't show any addresses
I'm using TCPView 4.16 for Windows 10 (downloaded from https://docs.microsoft.com/en-us/sysinternals/downloads/tcpview). Up until a few days ago it worked fine, but all of a sudden it simply stopped ...
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Device communicates with server through bridge, unable to capture all packages
I'm trying to reverse engineer a device to be able to access its API locally. Currently it is communicating with an online server, where I can log into to see its data.
Set up
The device connects ...
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Google and Youtube websites open even when Port 443 is blocked
I want to prevent internet access to one PC retaining the file and printer sharing.
For this, in Windows Firewall, I created a rule for Outbound Connection and blocked Ports 80 and 443.
After enabling ...
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Can TCP implementation send several packets without waiting an ACK for the first one?
I basically know who TCP works from sockets point of view, but I can't figure out some thing.
Suppose I have now 1000 bytes to send, it comes for TCP-stack internal buffer and gets sent. These bytes ...
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How to determine what application is sporadically sending tcp/udp traffic (peerblock) via state changes?
I use peerblock (which isn't the best, but it's something).
Anyways. When I'm not downloading anything. Peerblock activity drops to almost non existent, but occasionally I will see something pop up ...
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How can I identity which process is sending data to a certain host on Linux?
As per title, I want to figure out the process responsible for certain traffic. I can see the traffic in wireshark, but I don't know which process it is.
Is there any straightforward way to do it? I'm ...
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Prometheus Blackbox Exporter TCP probe returns value of 0, even when port is open (Iperf3 server)
I have a strange problem that I've been digging into the last couple of days.
The setup
I have an Iperf3 server running in Docker on this internal address and port: 10.10.2.2:5201
I also have ...
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Accessing Windows localhost from WSL2?
I have Windows 11 with WSL2 (Ubuntu) installed on it.
I've setup a gdb listener server on my Windows localhost and want to access it from Wsl2, but it seems my Windows machine and WSL are using ...
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Wireshark is not display the packets between the client and server
On my machine there a TCP server is running @port 54000 which is a echo server it sends the same message which is sent to it.
I have multiple clients which is connected to this server. Clients and the ...
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linux service TCP Gateway with service starting
Is there a service (linux) that starts the service on an incoming TCP request (if it does not already exist) and then forwards it to the application? For example, for a docker container that would ...
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How do I get traceroute to work like tcptraceroute?
On Mac OS 11 the man page for traceroute says you can set it to TCP mode with -P TCP. When I attempt to do this I get no responses:
[me@laptop ~]$ sudo traceroute -f 6 -m 10 -e -P TCP -p 443 www....
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Returning tcp/udp packets to sender
I'm using a Linux machine with WiFi hotspot to test the WiFi stack of an embedded device. For context, the embedded device is designed to send and receive encrypted packets to/from a remote server.
To ...
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How to investigate why a computer stops a TCP connection?
I've just written this question on another StackExchange site, but I was advised to ask the same question here.
I would like to broaden the question: how can I know why a host closes a TCP socket ...
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Kubeadm - unable to join nodes - request canceled while waiting for connection
Trying to provision k8s cluster on 3 Debian 10 VMs with kubeadm.
All vms have 2 network interfaces, eth0 as public interface with static ip, eth1 as local interface with static ips in 192.168.0.0/16:
...
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Address of a Transport layer?
In TCP/IP protocol stack following protocol level addresses exists:
Data Link layer - MAC address
Network layer - IP address
Transport layer - ?
Application layer - Socket address which is ...
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TCP server device for USB access readers
I have a BarCode reader that spits out data over a Virtual COM port (RS232 Serial) through a USB cable. I have a server running and managing a facility, and I need to read data coming off the BarCode ...
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How can I do a bi-directional Port-Forwarding (flow encapsulation)?
I have two applications: a client and a server which communicate through port 1234. For some reasons this port is blocked on our system but everything works correctly on port 1235 (checked with two ...
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TCP ports of Windows 10 PPTP VPN server
I have installed the PPTP VPN server on Windows 10 machine (incoming connection feature), I have created the NAT on port TCP 1723 and UDP 1701 in the router.
In the server machine there was an apache ...
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What's the minimum upstream bandwidth required for ACK packets in a TCP connection?
Consumer internet connections often feature asymmetrical bandwidth with just 10% of even 5% of upstream speed compared to downstream, for example 1000MBit/s downstream with 50MBit/s upstream speeds.
I ...
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How to show a HTTP stream from VLC Player in Wireshark?
I just set up a HTTP stream of a video between my Server and Client system using the VLC media player (using the command line). Both the systems run Ubuntu 20.04
vlc -vvv <path to video file> --...
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Connect a socket to another PC in same NAT
Hey I've got two machines on the same network. They get their IP info back from an external webserver. Same IP due to NAT but different ports locally. Hmm that's weird.. they can't socket up or even ...
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Why is the TCP MSS (Maximum Segment Size) 1460 bytes?
I'd like to know why the MSS value in the TCP header is 1460 bytes.
I know that the MTU for Ethernet networks is 1500 bytes, that the IP header is 20 bytes and the TCP header is 20 bytes.
But still, ...
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Mysterious TCP/HTTP issue accessing LaserJet Web Interface
I'm trying to diagnose a connectivity issue between my LaserJet M551dn
(lj500) and my FreeBSD system (hal9k). The problem is that I can no longer
browse the LaserJet's Web Interface (times out after ...
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How to run wireguard over tcp with udptunnel?
I'd like to run wireguard over tcp. I wanted to use udptunnel for sending udp packets over tcp. However, when I run wireguard and then try to run udptunnel, the udptunnel fails with the following ...
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TCP communcation - HyperV virtual machine opening port on host
Here's the summary of my fight to connect to a port on the hypervisor host from a VM hosted on the same machine:
Set up in the Hyper-V Manager:
Virtual Switch Settings
Internal
'Enable virtual LAN ...
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WebSocket connections originating from local network all use same client-side port (instead of ephemeral) when connecting to local webserver - Why?
I set up a webserver on a virtual machine on my home desktop. I have my router forward several ports (80, 443, etc) to my desktop, when then forwards them via NAT to the virtual machine (see diagram ...
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How to port forward UDP though SSH
I have a setup where I'm forwarding port 5000 to a remote server with ssh -NR 5000:localhost:5000 root@server This only forwards TCP packets through the SSH tunnel, Due to new software which is picky ...
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