Information Technology Reference
In-Depth Information
Technically, access to files on other machines can follow any of
three basic approaches:
1.
The user may make a copy of the centralized file and make
edits on that copy only, so that work on the local copy does
not affect the centralized version.
2.
A single copy of the file may be maintained on the network,
but that copy may move from one place to another, accord
ing to where the user is working at the moment.
3.
The user may work directly with the centralized copy of the file,
so changes made by the user will modify that centralized copy.
In practice, approaches 1 and 3 are in common use, whereas the
migration of files from location to location described in approach 2
is not used as frequently. Let's focus on the more popular ap
proaches here.
File Transfer Protocol: A particularly common approach for the
sharing of files involves a user requesting a copy of a file from a cen
tralized server. In this form of file sharing, each copy of a file is
maintained independently, and no effort is made to coordinate ver
sions. Stripped to its basic elements, the approach requires a user to
send a specific request for a file to a relevant server, and the file
server responds by sending back a copy of the desired file.
If Karen, Steve, and Ella used this model to share their group
project, they would decide on a common format for their paper—
perhaps Rich Text Format or (RTF), and they would maintain a sin
gle, common file as their standardized copy. Depending upon their
school's networking capabilities, this file could be located in one of
the students' directories mentioned earlier, or the file might be lo
cated on a commonly accessible file server, as shown in Figure 9.2.
Using this model for file sharing, the file server contains the most
recent draft of the full paper for the group. Karen, Steve, and Ella can
each access this file through the school network. If Ella, for example,
wanted to work on the document, she would download a copy of the
current full draft from the common file server to her own computer ac
count. She then could add materials and edit other sections, saving the
result back within her own account. When she was done, she would
upload the revised copy from her account back to the common server.
