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  • Is anyone aware of software (cheap) that can send packets of various sizes and protocols and also attaches sequence number to the packet?

    I would like to send these packets from a pc, thru wireless to another pc and look for: lost packets, out of sequence packets
    And also the latency of the packets.

    Thank you

  • Not sure if this will do the job or not but worth checking it out. Its free and I use it at times to find out the latency issues. Its called "netcps".
    cheers

  • You might try iperf. It will do some of what you're asking, including sending sequence numbered UDP packets for bandwidth testing. It will measure throughput for TCP and UDP.

    http://dast.nlanr.net/Projects/Iperf/

    The UDP can be sent at a specified bandwidth, constant rate like VoIP or video, which lets you see at what speed a specific setup falls over.

    An example --------

    This log is from two Windows PCs, each using the same 802.11g access point.

    In the reports below, sending bandwidth was first 14 Mbits/sec, which had only .92% packet loss and throughput of 13.9 Mbits/sec, jitter 2.089 ms.

    At 15 Mbits/sec sending bandwidth, 3.1% loss, throughput 14.5 Mbits/sec, jitter 1.172 ms.

    At 16 Mbits/sec, 19% loss, throughput 12.6 Mbits/sec, jitter 11.228 ms.
    ------------------------------------------------------------
    [1920] local 172.16.232.128 port 1989 connected with 10.0.1.4 port 5001
    [ ID] Interval Transfer Bandwidth
    [1920] 0.0-10.0 sec 16.7 MBytes 14.0 Mbits/sec
    [1920] Server Report:
    [1920] 0.0-10.0 sec 16.5 MBytes 13.9 Mbits/sec 2.089 ms 109/11906 (0.92%)
    [1920] Sent 11906 datagrams
    ------------------------------------------------------------
    Client connecting to 10.0.1.4, UDP port 5001
    Sending 1470 byte datagrams
    UDP buffer size: 8.00 KByte (default)
    ------------------------------------------------------------
    [1920] local 172.16.232.128 port 1990 connected with 10.0.1.4 port 5001
    [ ID] Interval Transfer Bandwidth
    [1920] 0.0-10.0 sec 17.9 MBytes 15.0 Mbits/sec
    [1920] Server Report:
    [1920] 0.0-10.0 sec 17.3 MBytes 14.5 Mbits/sec 1.172 ms 391/12757 (3.1%)
    [1920] Sent 12757 datagrams
    ------------------------------------------------------------
    Client connecting to 10.0.1.4, UDP port 5001
    Sending 1470 byte datagrams
    UDP buffer size: 8.00 KByte (default)
    ------------------------------------------------------------
    [1920] local 172.16.232.128 port 1991 connected with 10.0.1.4 port 5001
    [ ID] Interval Transfer Bandwidth
    [1920] 0.0-10.0 sec 19.1 MBytes 16.0 Mbits/sec
    [1920] Server Report:
    [1920] 0.0-10.3 sec 15.4 MBytes 12.6 Mbits/sec 11.228 ms 2596/13607 (19%)
    [1920] Sent 13607 datagrams

    If you use a protocol analyzer like OmniPeek or Wireshark at the receiving end (or both ends), you can tell more about what's going on.

    Charles Preston

  • CommView for Wi-Fi (www.tamos.com)

  • As a comparison with the previous posting on 802.11g throughput, here are some results for 802.11b.

    802.11b experiment with iperf

    Looking at the reports from iperf, sending UDP at a constant bitrate from one client to another through an access point, 802.11b, the UDP data rate before severe network degradation was 3 Mbits/sec.

    At a 3 Mbits/sec sending rate, measured UDP throughput was 3.02 Mbits/sec, with no packet loss.
    At a 4 Mbits/sec sending rate, measured UDP throughput was 2.62 Mbits/sec, with 33% packet loss.

    The same access point and clients were then set to 802.11g only, and UDP throughput at 9 Mbits/sec had no packet loss. This means the results probably were a WLAN limitation, and not a problem with wireless drivers, busy client computers, etc.

    iperf -c 192.168.1.101 -u -b 3m
    ------------------------------------------------------------
    Client connecting to 192.168.1.101, UDP port 5001
    Sending 1470 byte datagrams
    UDP buffer size: 8.00 KByte (default)
    ------------------------------------------------------------
    [1920] local 172.16.232.128 port 1295 connected with 192.168.1.101 port 5001
    [ ID] Interval Transfer Bandwidth
    [1920] 0.0-10.0 sec 3.58 MBytes 3.00 Mbits/sec
    [1920] Server Report:
    [1920] 0.0-10.0 sec 3.58 MBytes 3.02 Mbits/sec 3.808 ms 0/ 2553 (0%)
    [1920] 0.0-10.0 sec 4 datagrams received out-of-order
    [1920] Sent 2553 datagrams

    iperf -c 192.168.1.101 -u -b 4m
    ------------------------------------------------------------
    Client connecting to 192.168.1.101, UDP port 5001
    Sending 1470 byte datagrams
    UDP buffer size: 8.00 KByte (default)
    ------------------------------------------------------------
    [1920] local 172.16.232.128 port 1296 connected with 192.168.1.101 port 5001
    [ ID] Interval Transfer Bandwidth
    [1920] 0.0-10.0 sec 4.77 MBytes 4.00 Mbits/sec
    [1920] Server Report:
    [1920] 0.0-10.2 sec 3.19 MBytes 2.62 Mbits/sec 5.961 ms 1125/ 3403 (33%)
    [1920] 0.0-10.2 sec 283 datagrams received out-of-order
    [1920] Sent 3403 datagrams

    Charles Preston

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