Questions tagged [tcp-window-scaling]
TCP congestion control depends on window scaling
21
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Receiver limits TCP window size to 64,512
Facts (please identify any false statements):
I have a 100 Mbps connection between two sites that are 80 ms apart
This is a long fat connection that could benefit from a large TCP window size perhaps ...
- 351
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3
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TCP Window Scaling for Satellite Connections
A satellite connection generally has a RTT around 500ms. Connections generally suffer sub-optimal transfer speeds, in spite of large amounts of bandwidth because TCP acknowledgements take too long to ...
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6
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Dropped packets, on recieve only, Server 2008 only, and network speed is 100mb/s
I have a really strange one.
I have packet loss with Excessive 'TCP Dup ACK' & 'TCP Fast Retransmission' when I download files (and only download) from two different Windows 2008 servers. Upload ...
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4
votes
1
answer
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Cisco ASA 5505, tcp window scaling (rfc1323)
I have a very odd issue with our cisco firewall,
If on our osx machines we run the following to disable window scaling support:
sudo sysctl -w net.inet.tcp.rfc1323=0
We see near 40% improvement ...
- 2,063
3
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3
answers
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better alternative for tcp_syncookies in linux
In an effort to prevent DDOS attacks I followed suggestions to leave /proc/sys/net/ipv4/tcp_syncookies value set to 1 in my linux box to enable TCP syncookies.
However, when I look at this URL: http:/...
user286228
3
votes
1
answer
811
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On a TCP connection, can the recipient control the TCP window size that the sender uses?
The TCP window size is the amount of data that the sender will send before waiting for a TCP ack. Does the receiver have a way to control this (e.g., as part of the TCP handshake), or is it only the ...
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2
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How to edit TCP window size from iptables?
There is TCPMSS target to edit MSS value of connections (including forwarded).
How to edit window size (for example, cap to some maximum value) by iptables rule?
Expecting something like
iptables -...
- 841
3
votes
0
answers
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TCP Window Scaling Not Working Between Windows 10 and Linux Server
We are having some issues with several clients running Windows 10 downloading files from our HTTP file delivery server.
We can't reproduce the error on our end but notice that TCP window scaling is ...
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2
votes
1
answer
177
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Why can't I reliably send or recieve data over TCP after moving servers?
I am currently dealing with a networking problem on high latency (100-400ms) Internet links. I run a Minecraft network, and I recently moved it to a separate datacenter to get a server with a better ...
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0
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How to change tcp's window size?
I've tried changing the tcp's window size by modifying net.ipv4.tcp_wmem and net.ipv4.tcp_rmem values, however the changes which I make have no effect on actual window size which I can check using a ...
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1
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Dynamic TCP window sizes
During the 3-way handshake, sender (10.16.0.128) and recipient (10.16.0.5) advertised their window size of 42340 and 65535 respectively.
From the 3rd packet (syn+ack+ack) onwards sender again ...
- 87
1
vote
1
answer
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How to adjust TCP Window Size?
I asked a similar question before, but I believe I was not clear with the details.
I'm basically having some problems with my server related to high latency between the server and the clients due to ...
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1
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2
answers
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FreeBSD slow transfers - RFC 1323 scaling issue?
I think I may be having an issue with window scaling (RFC 1323) and am hoping that someone can enlighten me on what's going on.
Server: FreeBSD 9, apache22, serving a static 100MB zip file. 192.168....
- 186
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0
answers
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Troubleshooting low TCP transfer rate behind a router
I’m trying to debug a low tcp transfer rate on a host (“lowHost”).
As a reference, i’m comparing it against a second host (“highHost”).
I’m making two rate measurements:
Downloading a big file using ...
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1
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0
answers
2k
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View / tweak TCP window size settings on Ubuntu 1804
I have a typical long fat network -- clients connect to servers with large bandwidth but also significant latency due to geographic distances of 30ms to 100ms, transferring large files.
I've noticed ...
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0
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windows server 2012 tcp window not scaling
I've got 2 windows 2012 servers that limit connection speed to anywhere from 1-3mBps and it seems to be related to tcp window scaling. Both servers have these settings
TCP Global Parameters
--------...
- 11
1
vote
1
answer
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IIS on Server 2012 R2 serving very slowly to remote clients
We've been trying to debug very slow transfer rates for remote clients hitting our web server (IIS on 2k12 R2).
The RTT to the client is about 150ms, and we're struggling to get more than about ...
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2
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Are we still limited by TCP Window Size when we want to fully utilize bandwidth from far away servers? [closed]
According to this website, as soon as round-trip time is increased, we lose a bit of our real-time capacity throughput to distant servers using default TCP Window size of 64KB.
My network bandwidth is ...
- 1
0
votes
0
answers
228
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Bytes-in-flight higher than receiver window in frozen client connections
I am dealing with sort of a "ghost issue". We have an endpoint URL that some people can use at all times with no issues but others have a frozen connection on the client side (checked with ...
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1
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localhost loopback tcp connection in Windows: increase the bottleneck of 65535 bytes per segment
The scenario that I have is as such: I have a loopback TCP session and I want to improve its performance. I have my socket-like objects (System.Net.Sockets in .NET Framework, to be specific) sending ...
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1
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How to determine the bottleneck of a given network
Consider an Access Point with a packet queue that can hold up to 50 packets and a network whose bottleneck is a link with a datarate of 50 Mbit/s.
There are quite a few nodes connecting wirelessly ...
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