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[Chapter 13] 13.4 Retrieving RFCs

[Chapter 13] 13.4 Retrieving RFCs

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[Chapter 13] 13.4 Retrieving RFCs

In another example the network administrator does not know which RFCs contain the information she
is looking for, but she knows what she wants. The administrator is trying to find out more about the
SMTP service extensions that have been proposed for Extended SMTP. Figure 13.6 shows the four
RFCs displayed as a result of her query.
Figure 13.6: An RFC Web search

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[Chapter 13] 13.4 Retrieving RFCs

The Web provides the most popular and best method for browsing through RFCs. However, if you
know what you want, anonymous FTP can be a faster way to retrieve a specific document. RFCs are
stored at ds.internic.net in the rfc directory. It stores the RFCs with filenames in the form rfcnnnn.txt
or rfcnnnn.ps, where nnnn is the RFC number and txt or ps indicates whether the RFC is ASCII text or
PostScript. To retrieve RFC 1122, ftp to ds.internic.net and enter get rfc/rfc1122.txt at the ftp>
prompt. This is generally a very quick way to get an RFC, if you know what you want.
To help you find out which RFC you do want, get the rfc-index.txt file. It is a complete index of all
RFCs by RFC number, and it's available from ds.internic.net in the rfc directory. You'll only need to

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[Chapter 13] 13.4 Retrieving RFCs

get a new RFC index occasionally. Most of the time, the RFC you're looking for has been in
publication for some time and is already listed in the index. Retrieve the RFC index and store it on
your system. Then search it for references to the RFCs you're interested in.

13.4.1 Retrieving RFCs by mail
While anonymous FTP is the fastest way and the Web is the best way to get an RFC, they are not the
only ways. You can also obtain RFCs through electronic mail. Electronic mail is available to many
users who are denied direct access to Internet services because they are on a non-connected network
or are sitting behind a restrictive firewall. Also, there are times when email provides sufficient service
because you don't need the document quickly.
Retrieve RFCs through email by sending mail to mailserv@ds.internic.net. Leave the Subject: line
blank. Request the RFC in the body of the email text, preceding the pathname of the RFC with the
keyword FILE. In this example, we request RFC 1258.
% mail mailserv@ds.internic.net
FILE /rfc/rfc1258.txt
The technique works very well. In the time it took to type these paragraphs, the requested RFC was
already in my mailbox.

Previous: 13.3 Finding Files
13.3 Finding Files

TCP/IP Network
Book Index

Next: 13.5 Mailing Lists
13.5 Mailing Lists

[ Library Home | DNS & BIND | TCP/IP | sendmail | sendmail Reference | Firewalls | Practical Security ]

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[Chapter 13] 13.5 Mailing Lists

Previous: 13.4 Retrieving

Chapter 13
Internet Information

Next: 13.6 The White Pages

13.5 Mailing Lists
Mailing lists bring together people with similar interests to exchange information and ideas. Most mailing
lists run under usage guidelines that restricted discussion to a specific topic. Mailing lists are often used as
places to report problems and get solutions, or to receive announcements. Some mailing lists are digests of
There is an enormous number of mailing lists. The list-of-lists contains information about many of the
mailing lists that are of interest to network administrators. [4] Use a Web browser to search for mailing lists
that interest you at http://catalog.com/vivian/interest-group-search.html. If you prefer, the list-of-lists can be
downloaded via anonymous FTP from nisc.sri.com in the file netinfo/interest-groups.txt and searched with
standard UNIX tools. Either way, you get the same information. The following example is the list-of-lists
entry for the Berkeley Internet Name Domain (BIND) software mailing list:
[4] Despite its large size, not every network administration mailing list is contained in the
interest-groups.txt file. You hear about some lists by word of mouth.
Subscription Address: bind-request@uunet.uu.net
This list covers topics relating to Berkeley Internet Name Domain
(BIND) domain software.
The entry has four sections: the address of the mailing list, the address to which subscription requests are
sent, the address of the owner, and a description of the list.
When you find a list you wish to join, don't send mail directly to the list asking to be enrolled. Instead, send
the enrollment request to the subscription address, which identifies the person or process that maintains the
list. If the list is manually maintained, as in the BIND example above, send your enrollment request to listname-request@host where list-name is the actual name of the list, and is followed by the literal string request. The -request extension is widely used as the address for administrative requests, such as being
added to or dropped from a list, when lists are manually maintained. For example, to join the BIND mailing
list, send your enrollment request to bind-request@uunet.uu.net. All other correspondence is sent directly to
Many mailing lists automate list management with programs like majordomo and LISTSERV. You can tell
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[Chapter 13] 13.5 Mailing Lists

the type of server being used by looking at the subscription address in the list-of-lists. The user portion of
that address will be either "majordomo" or "LISTSERV," depending on the server being used. To subscribe
to a majordomo list, send email to the subscription address and type the following in the body of the
subscribe list-address your-address
where list-address is the address of the email list, and your-address is your email address.
To subscribe to a LISTSERV mailing list, send email to the subscription address with the following in the
message body:
subscribe list your-name
where list is the name of the list, not necessarily its address, as that name appears in the first line of its listof-lists entry. your-name is your first and last name. This is not your email address. LISTSERV takes
your email address from the email headers.

13.5.1 Newsgroups
A mailing list is one way of distributing announcements and exchanging questions and answers, but it is not
the most efficient way. A mail message is sent to every person on the list. It is sent immediately, and it must
be stored on the local system until it is read. Thus, if there are 100 people on a list, 100 messages are sent
over the network and stored at 100 receiving systems. Network news provides a more efficient method for
distributing this kind of information. The information is stored around the network on, for most sites, one or
two news servers. Therefore, instead of moving mail messages to every individual on your network who
wants to discuss the Linux operating system, news articles about Linux are stored at one location where they
can be read when the user is ready. Not only does this reduce the network load, it reduces the number of
redundant copies that are stored on local disk files.
Network news is delivered over TCP/IP networks using the Network News Transfer Protocol (NNTP).
NNTP is included as part of the TCP/IP protocol stack on most UNIX systems and requires no special
configuration. The only thing you need to know to get started is the name of your closest network news
server. Ask your ISP. Most ISPs provide network news as part of their basic service.
NNTP is a simple command/response protocol. The NNTP server listens to port 119:
% telnet news.nuts.com 119
Connected to news.nuts.com.
Escape character is ']'.
200 news.nuts.com ready (posting ok).
Connection closed by foreign host.
A help command sent to this server would have produced a list of 23 NNTP commands. Luckily this is not
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