User's Manual

Setup and Test
153
Please refer to the technical note at the end of this section, explaining why the figure
will be less than the theoretical maximum data rate available.
10. To exit from the FTP program, type “quit” at the prompt
Creating batch files for automatic File Transfers:
As mentioned earlier, it will be much more convenient to have test batch files which will
automatically perform a file transfer, and then pause to show the results. The
command-line FTP program described above can be instructed to use a script file with
a set of commands, thus preventing the need to type them every time.
Included in the embedded .zip file below are sample files to perform a 10Mbyte
download, and a 1Mbyte upload. They are explained below, and if you use them you
will need to unzip them into your working FTP directory, and then edit them to use an
appropriate IP address for your FTP Server. The files are very small and easy to
create, if you do not have a paper copy of this document
The FTP program can be invoked using the syntax:
ftp –s:filename Where “filename” specifies a text file containing FTP commands; the
commands will automatically run after FTP starts.
The commands will be almost identical to those used in the “manual” method above,
the difference is the use of the “open” command to connect the FTP program to the
FTP server. A worked example (note text after the // are comments and must not be
included in the file):
Contents of “10MB_Download.bat”
ftp -s:10M_Download_Script.txt // invoke the FTP program using a script
pause // wait for a key press, so you can see the results
Contents of “10M_Download_Script.txt”
Open 10.0.60.1 // Server IP address: change this to match yours
ftp // Username for anonymous access
[e-mail] // A password, in “email” format
bin // Change to Binary mode
hash // Turn on “hash marking”
recv 10M 10M_ downloadedfile // Get the file “10M” and rename it locally
quit // Exit the program
To automatically send a file, you will also need another batchfile to call the FTP
program with a different script file. The script file will be the same as the one above,
except the “recv 10M 10M_downloadedfile” command will be replaced with, e.g. “send
1M 1M_uploadedfile”.
Technical Note: An explanation of Ethernet, and Airspan protocol overheads in FTP
transfers:
The structure and relative sizes of the different portions of an Ethernet frame vary, but
a full sized FTP data transfer Ethernet Frame is 1514 Bytes, consisting typically of:
1. 14 Bytes Data Link Control (layer 2 of the OSI 7 Layer model):
Containing 6 bytes each of source & sestination MAC addresses, and 2
bytes Ethertype – in this case IP;
2. 20 Bytes Network Layer (layer 3 – in this case IP):Containing source
and destination IP addresses, and other information such as IP version,
Length, TTL, protocol, checksum, and several flags;
3. 20 Bytes Transport Layer (layer 4 – in this case TCP):Containing source
& destination Port numbers, sequence and ACK numbers, TCP Receive
Window size, User Data offset position, a checksum, and some flags;
4. 1460 Bytes Application Layer (layer 7 – in this case FTP) – the actual
file contents being transferred.