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A Whole New Section: The new FTP server:
The arrival of version 1.50 brings networking to the SX-1. As an FTP file server, files can be moved to and
from the SX-1 using a remote FTP client on the same network. This means that a computer connected to
the SX-1 via an ethernet network could access the project-specific files on drives connected to it.
Getting the FTP server running will require a brief and simple explanation of general networking principles.
Attempts will be made to be as concise and complete as possible, but keep in mind that entire texts have
been written about the subject, and it will be impossible to encapsulate everything there is to know about
the joys of networking in the limited amount of space provided here. Bear in mind as well that as in most
technological discussions, differences can be expected as the complexity of a system grows. The concepts
explained herein apply to the lion s share of networking situations you will encounter, but there are almost
always other ways to do similar things. If you are familiar enough to know other methods and hardware
that can be utilized to get the same results, this section is probably beneath your knowledge level anyway.
These concepts will be listed separately to aid in comprehension.
Network Basics:
1.
First concept: Ethernet communication
Networks of the kind being discussed here are created utilizing the ethernet protocol. An ethernet
connector looks much like a larger telephone jack (you will find one next to the SCSI connection on
the back of your SX-1 for reference), and has multiple pins inside for carrying a large amount of
information back and forth.
The data is carried back and forth between clients (in general, computers connected to the network) in
groups of bits commonly referred to as packets . These packets travel around the entire network and
back almost like a conveyor belt. The only thing you really need to know is that each packet contains
not only the information itself to be transmitted, but also routing information about exactly where the
data should go.
Ask yourself this question:
if you have multiple computers connected to the same network, how does
some data know to only go to certain computers and not all of them?
The answer is by the use of specific addresses for each of the computers in the network, called IP
addresses .
2.
Second concept: The IP address number
In order to keep all of this data going back and forth to the right places —
so that all of the computers
don t get copies of all the information sent back and forth by each other —
an IP address is used. IP
stands for Internet Protocol , which for our purposes refers to our network. Internet , after all, is
actually Internal Network shortened.
The IP address acts just like the address of your home works for the mail system: your home address
provides a specific location that someone can use to send mail to you.
Think about what happens when a friend of yours from another city sends you mail: your friend puts
the letter in the mailbox, and a postman picks up the mail and delivers it to the post office. At the post
office, your letter is sorted by the address printed on the front of the envelope, and sent to your town.
In your town, the postman who has your home on his route is given your letter to deliver to your
m a i l b o x . U s i n g y o u r s t r e e t a n d n u m b e r , t h e p o s t m a n d e l i v e r s y o u r m a i l .
This is very similar to the way that a network operates. The only thing you have to keep in mind is that
there are no streets in an ethernet network (35 Maple Drive will get you
nowhere
in the Land of
Ethernet), so numbers are substituted.