Network Working Group J. Postel Request for Comments: 1543 ISI Obsoletes: RFCs 1111, 825 October 1993 Category: Informational
InstrUCtions to RFCAuthors
Status of this Memo
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Informational
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Protocol
This protocol is intended to provide the bla-bla service, and be used between clients and servers on host computers. Typically the clients are on workstation hosts and the servers on mainframe hosts.
or
This protocol is intended to provide the bla-bla service, and be used between special purpose units such as terminal servers or routers and a monitoring host.
Discussion
The purpose of this RFCis to focus discussion on particular problems in the Internet and possible methods of solution. No proposed solutions in this document are intended as standards for the Internet. Rather, it is hoped that a general consensus will emerge as to the appropriate solution to such problems, leading eventually to the adoption of standards.
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These paragraphs need not be followed word for word, but the general intent of the RFCmust be made clear.
7. References Section
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8. Security Considerations Section
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10. Relation to other RFCs
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OBSOLETES
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For example:
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UPDATED-BY
To be used to refer to the newer section(s) which are to be added to the existing, still used, document.
11. Protocol Standards Process
See the current "Internet Official Protocol Standards" (STD 1) memo for the definitive statement on protocol standards and their publication [1].
The established procedure is that when the IESG completes work on a document that is to become a standards track RFCthe communication will be from the Secretary of the IESG to the RFCEditor. Generally, the documents in question are Internet Drafts. The communication usually cites the exact Internet Draft (by file name) in question. The RFCEditor must assume that only that file is to be processed to become the RFC. If the authors have small corrections to the text, they should be sent to the RFCEditor separately (or as a "diff"), do not send a new version of the document.
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14. RFCIndex
Several organizations maintain RFCIndex files, generally using the file name "rfc-index.txt". The contents of such a file copied from one site may not be identical to that copied from another site.
15. Security Considerations
This RFCraises no security issues (however, see Section 6).
16. References
[1] Postel, J., "Internet Official Protocol Standards", STD 1, RFC 1540, Internet Architecture Board, October 1993.
17. Author's Address
Jon Postel USC/Information Sciences Institute 4676 Admiralty Way Marina del Rey, CA 90292
Generally, we use the very simplest nroff features. We use the "ms" macros. So, "nroff -ms input-file > output-file". However, we could not get nroff to do the right thing about putting a form feed after the last visible line on a page and no extra line feeds before the first visible line of the next page. We want:
last visible line on page i ^L first visible line on page i+1
So, we invented some hacks to fix this including a "sed" script called "fix.sh" and a "c" program we called "pg" (pg is called from fix). So the command to process the file becomes:
nroff -ms input-file fix.sh > output-file
Now as to the nroff features we actually use, I'll append a sample memo, prepared in RFCstyle.
The sed script fix.sh is:
sed -e 's/FORMFEED/[Page/ /[Page/' $* pg -n5
The pg program is:
~~~Beginning of pg program~~~
/* $Header$ * * Remove N lines following any line that contains a form feed (^L). * (Why can't this be done with awk or sed?) * * OPTION: * -n# Number of lines to delete following each ^L (0 default). * $Log$ */ #include <stdio.h> #define FORM_FEED '/f' #define OPTION "n:N:" /* for getopt() */
extern char *optarg; extern int optind;
main(argc, argv) int argc; char *argv[];
{ int c, /* next input char */ nlines = 0; /* lines to delete after ^L */ void print_and_delete(); /* print line starting with ^L, then delete N lines */
/* Process option (-nlines) */
while ((c = getopt(argc, argv, OPTION)) != EOF) switch(c) { case 'n' : case 'N' : nlines = atoi(optarg); break; } /* READ AND PROCESS CHARS */
while ((c = getchar()) != EOF) if (c == FORM_FEED) print_and_delete(nlines); /* remove N lines after this one */ else putchar(c); /* we write the form feed */ exit(0); }
/* Print rest of line, then delete next N lines. */
void print_and_delete(n) int n; /* nbr of lines to delete */ { int c, /* next input char */ cntr = 0; /* count of deleted lines */
while ((c = getchar()) != '/n') /* finish current line */ putchar(c); putchar('/n'); /* write the last CR */ putchar(FORM_FEED);
for ( ; cntr < n; cntr++) while ((c = getchar()) != '/n') if (c == EOF) exit(0); /* exit on EOF */ putchar(c); /* write that last CR */ } ~~~End of pg program~~~
.pl 10.0i .po 0 .ll 7.2i .lt 7.2i .nr LL 7.2i .nr LT 7.2i .ds LF Waitzman .ds RF FORMFEED[Page %] .ds CF .ds LH RFC1149 .ds RH 1 April 1990 .ds CH IP Datagrams on Avian Carriers .hy 0 .ad l .in 0 Network Working Group D. Waitzman Request for Comments: 1149 BBN STC 1 April 1990
.ce A Standard for the Transmission of IP Datagrams on Avian Carriers
.ti 0 Status of this Memo
.fi .in 3 This memo describes an experimental method for the encapsulation of IP datagrams in avian carriers. This specification is primarily useful in Metropolitan Area Networks. This is an experimental, not recommended standard. Distribution of this memo is unlimited.
.ti 0 Overview and Rational
Avian carriers can provide high delay, low throughput, and low altitude service. The connection topology is limited to a single point-to-point path for each carrier, used with standard carriers, but many carriers can be used without significant interference with each other, outside of early spring. This is because of the 3D ether space available to the carriers, in contrast to the 1D ether used by IEEE802.3. The carriers have an intrinsic collision avoidance system, which increases availability. Unlike some network technologies, such as packet radio, communication is not limited to line-of-sight distance. Connection oriented service is available in some cities, usually based upon a central hub topology.
.ti 0 Frame Format
The IP datagram is printed, on a small scroll of paper, in hexadecimal, with each octet separated by whitestuff and blackstuff. The scroll of paper is wrapped around one leg of the avian carrier. A band of duct tape is used to secure the datagram's edges. The bandwidth is limited to the leg length. The MTU is variable, and paradoxically, generally increases with increased carrier age. A typical MTU is 256 milligrams. Some datagram padding may be needed.
Upon receipt, the duct tape is removed and the paper copy of the datagram is optically scanned into a electronically transmittable form.
.ti 0 Discussion
Multiple types of service can be provided with a prioritized pecking order. An additional property is built-in worm detection and eradication. Because IP only guarantees best effort delivery, loss of a carrier can be tolerated. With time, the carriers are self-regenerating. While broadcasting is not specified, storms can cause data loss. There is persistent delivery retry, until the carrier drops. Audit trails are automatically generated, and can often be found on logs and cable trays.
.ti 0 Security Considerations
.in 3 Security is not generally a problem in normal Operation, but special measures must be taken (such as data encryption) when avian carriers are used in a tactical environment.
.ti 0 Author's Address
.nf David Waitzman BBN Systems and Technologies Corporation BBN Labs Division 10 Moulton Street Cambridge, MA 02238
