What is iperf retr?
In iperf3 the column Retr stands for Retransmitted TCP packets and indicates the number of TCP packets that had to be sent again (=retransmitted). The lower the value in Retr the better. An optimal value would be 0, meaning that no matter how many TCP packets have been sent, not a single one had to be resent.
What is UDP buffer size in iperf?
The length of buffers to read or write. Iperf works by writing an array of len bytes a number of times. Default is 8 KB for TCP, 1470 bytes for UDP.
Is iperf compatible with iPerf3?
iperf3 is a new implementation from scratch, with the goal of a smaller, simpler code base, and a library version of the functionality that can be used in other programs. iperf3 is not backwards compatible with iperf2. x….iperf2 / iperf3.
| Server: | |
|---|---|
| iperf -s -w 32M -D / iperf3 -s -D | Start server with larger TCP window, and in daemon mode |
Is iperf3 bidirectional?
All in all, the bidirectional tests between iPerf2 and iPerf3 are very similar. The only advantage of iPerf3 is that it doesn’t require a reverse route or port open to receive the traffic since both sockets are opened from the client to the server.
How do I test iperf3?
Just place the iPerf3.exe file on both the client and server systems in a folder contained in a system path — or one accessible via change directory — and you are ready to go. The role of each station — client or server — is determined by switches at runtime.
Is iperf secure?
Yes, this is reasonably safe. People do this all the time, and they tend to be people who are sensitive to network security issues. iperf3 is a rewrite of the original iperf software and has received more scrutiny then the original package, and iperf3 was created at a time when network security really does matter.
Why is iperf UDP slower than TCP?
On the other hand when you send a TCP stream iperf does bookkeeping only once per stream. In my measurements it came out that iperf-UDP wastes a lot of time doing the per-datagram measurements hence the slower performance.
Is iperf3 open source?
Iperf is open-source software written in C, and it runs on various platforms including Linux, Unix and Windows (either natively or inside Cygwin).
Why is iperf TCP slower than UDP?
On the other hand when you send a TCP stream iperf does bookkeeping only once per stream. In my measurements it came out that iperf-UDP wastes a lot of time doing the per-datagram measurements hence the slower performance. If you really want to compare TCP vs UDP performance is better to write your own test program.
Is TCP or UDP more efficient?
TCP is a connection-oriented protocol, whereas UDP is a connectionless protocol. A key difference between TCP and UDP is speed, as TCP is comparatively slower than UDP. Overall, UDP is a much faster, simpler, and efficient protocol, however, retransmission of lost data packets is only possible with TCP.