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FTP File Transfer Performance Analysis

Start your analyzer.
Start an FTP transfer (binary mode) of a 20MB (minimal) file.
Stop your analyzer.
Use the trace file Matrix to filter on just FTP-Ctrl, FTP-Data, and DNS(UDP)
Save the original trace as Original_20MB_FTP_File_Transfer.caz
Search for “RETR” which denotes the FTP Control command to start the FTP transfer.
Go backwards in the frame order until you see the FTP Text on port 20 indicating the files that were listed with the user commands “dir” or “ls”: open that frame, and record the name and file size of the file you downloaded. Go to the start of the file transfer for that particular file.

Filter on just port 20 and the clilent data port associated with that 20MB file transfer.
Save that trace file as 20MB_FTP_File_Transfer.caz
Start your calculations for Throughput, Overhead, and Efficiency
    a. Throughput = Cumulative Bytes / Relative Time

        i. The value should be close to 200KB/s over T1

        ii. Otherwise check for others using the 'pipe', Long Acks, Retransmissions.
    b. Overhead = ((Cumulative Bytes – File Size) / Cumulative Bytes) / 100 
        i. The value must be less than 15%
        ii. Otherwise check for frame size, MTU, Retransmissions.
    c. Efficiency = 100 – Overhead 
        i. The value must be greater than 85%

Do this periodically on your most important segments to judge the relative health of the network.