RFC 977 (rfc977) - Page 2 of 27
Network News Transfer Protocol
Alternative Format: Original Text Document
RFC 977 February 1986
Network News Transfer Protocol
1.2. The USENET News System
Clearly, a worthwhile reduction of the amount of these resources used
can be achieved if articles are stored in a central database on the
receiving host instead of in each subscriber's mailbox. The USENET
news system provides a method of doing just this. There is a central
repository of the news articles in one place (customarily a spool
directory of some sort), and a set of programs that allow a
subscriber to select those items he wishes to read. Indexing,
cross-referencing, and expiration of aged messages are also provided.
1.3. Central Storage of News
For clusters of hosts connected together by fast local area networks
(such as Ethernet), it makes even more sense to consolidate news
distribution onto one (or a very few) hosts, and to allow access to
these news articles using a server and client model. Subscribers may
then request only the articles they wish to see, without having to
wastefully duplicate the storage of a copy of each item on each host.
1.4. A Central News Server
A way to achieve these economies is to have a central computer system
that can provide news service to the other systems on the local area
network. Such a server would manage the collection of news articles
and index files, with each person who desires to read news bulletins
doing so over the LAN. For a large cluster of computer systems, the
savings in total disk space is clearly worthwhile. Also, this allows
workstations with limited disk storage space to participate in the
news without incoming items consuming oppressive amounts of the
workstation's disk storage.
We have heard rumors of somewhat successful attempts to provide
centralized news service using IBIS and other shared or distributed
file systems. While it is possible that such a distributed file
system implementation might work well with a group of similar
computers running nearly identical operating systems, such a scheme
is not general enough to offer service to a wide range of client
systems, especially when many diverse operating systems may be in use
among a group of clients. There are few (if any) shared or networked
file systems that can offer the generality of service that stream
connections using Internet TCP provide, particularly when a wide
range of host hardware and operating systems are considered.
NNTP specifies a protocol for the distribution, inquiry, retrieval,
and posting of news articles using a reliable stream (such as TCP)
server-client model. NNTP is designed so that news articles need only
Kantor & Lapsley