Network Working Group P. David Lebling Request for Comments: 751 (PDL@MIT-DMS) NIC: nnnnn 10 December 1978
SURVEY OF FTP MAIL AND MLFL
Two surveys of Arpanet Server hosts were run between September 20, 1978 and December 11, 1978. The intent was to determine the response of the host's Server FTP program to:
(a) An attempt to mail to an unknown recipient at that host. The purpose of this survey was two-fold. First, to determine whether the host accepts mail for unknown recipients at all, and second, what response the host gives if it does not accept such mail.
(b) An attempt to mail to a known recipient using the MLFL command rather than the usual MAIL command. This survey was undertaken to determine the extent of support for the MLFL command among Server hosts, and the sort of reply received if the Server does not support MLFL. MLFL is potentially a 'better' form of communication than mail as the message is sent over a data connection rather than the command connection. Using the data connection eliminates the 'end-of-mail' marker and 'command reader' problems sometimes encountered over the command connection.
The ground rules of the survey were that all sites listed as Servers in the MIT/SAIL Host table were surveyed. In many cases, a host listed as a Server would not respond to an ICP at any time during the period of the survey. Once a host responded with what seemed to me to be a 'definitive' answer, I marked it as such and stopped surveying it.
MLFL Survey
The algorithm used was to ICP to socket 3 of the server (the standard old-FTP socket). Once a 300 response was received, I sent the MLFL command. Where I had the name of a real mailbox at a site (a Header-person, for example) I used that, otherwise the name "**". If a site asked for a password (response 504) after the MLFL command I gave "USER NETML" "PASS NETML" and retried the MLFL. If the server replied with a 255 SOCK command, I listened for the data-connection to be established. When it was, I transferred the mail file. Interestingly enough, most sites implement an RFC queueing algorithm that will allow the user site to attempt to establish the data-connection from its end.
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NWG/RFC 751 PDL 10 Dec 78 nnnnn Survey of FTP MAIL and MLFL
Complete FTP scripts may be found, if you are interested, on MIT-DM, file NETDOC;MLFL SURVEY.
Sites are grouped by the general result they gave.
-site- -last ftp reply if lost- -when-
1) Sites that lost for various reasons:
BNL 530 NOT LOGGED IN. after MLFL HARV-10 431 INVALID ENTRY - Try again after USER LLL-MFE 454 Login please after SOCK LONDON 000 INDRA FTP Version 2.00 ... after ICP NBS-10 454 Login please after SOCK WHARTON 454 DATA Connection error ... after SOCK WPAFB-AFAL 454 Login please after SOCK
Note: "when" describes the last action performed by the surveyer before the indicated anomalous response.
after ICP -- surveyer had done ICP to socket 3 after MLFL -- surveyer had sent MLFL command after USER -- surveyer had sent USER NETML in response to "504 Login please" after SOCK -- surveyer had attempted to connect to specified data socket
4) Sites that support MLFL but require "USER NETML" "PASS NETML" (Multics):
MIT-MULTICS RADC-MULTICS
5) Others:
a) Sites that might support it if I could mail to a real user (some of these run operating systems that are "known to work", e.g. TENEX):
BBN-TENEXB 450 No such mailbox at this site. CCA-SDMS 450 User Unknown CCTC 451 User Not Recognized CMU-10D 507 USER NOT FOUND: ** DTI 451 User Not Recognized LL-11 450 User Unknown LL-XN 450 User Unknown NCSC 451 User Not Recognized NOSC-CC 451 User Not Recognized NOSC-SDL 451 User Not Recognized NTIA-ITS 451 User Not Recognized OFFICE-2 450 No such mailbox at this site. RADC-XPER 451 User Not Recognized SDAC-44 431 User name invalid SDAC-UNIX 451 User Not Recognized SRI-UNIX 451 User Not Recognized
b) Sites that either never responded to an ICP to socket 3, or were not accepting FTP users:
NWG/RFC 751 PDL 10 Dec 78 nnnnn Survey of FTP MAIL and MLFL
MAIL Survey
The mechanics of the MAIL survey were similar to those of the MLFL survey. The command was "MAIL Fzorkness" (an account unlikely to exist on any host). The responses are grouped into a few general categories.
Complete FTP results may be found on MIT-DM, file NETDOC;MAIL SURVEY.
-site- -last response-
1) Sites that lost completely.
LONDON 000 INDRA FTP Version <>.00 ...
2) Sites that accept mail to an unknown recipient.
3) Sites that refuse mail to an unknown recipient (grouped by response).
SDAC-44 431 User name invalid
BBN-TENEX 450 No such mailbox at this site. BBN-TENEXA 450 No such mailbox at this site. BBN-TENEXB 450 No such mailbox at this site. BBN-TENEXD 450 No such mailbox at this site. BBN-TENEXE 450 No such mailbox at this site. BBN-UNIX 450 User Unknown CCA-SDMS 450 User Unknown CCTC 451 User Unknown EDN-UNIX 450 User Unknown I4-TENEX 450 No such mailbox at this site. ILL-UNIX 450 User unknown LL 450 No such mailbox at LL LL-ASG 450 User unknown LL-XN 450 User unknown MIT-MULTICS 450 Cannot locate mailbox for \Fzorkness\ MIT-XX 450 No such mailbox at this site. NBS-UNIX 450 User Unknown NCSC 450 User Unknown NOSC-CC 450 User Unknown NOSC-SDL 450 User Unknown NTIA-ITS 450 User Unknown OFFICE-1 450 No such mailbox at this site. OFFICE-2 450 No such mailbox at this site. PARC-MAXC 450 No such mailbox at this site.
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NWG/RFC 751 PDL 10 Dec 78 nnnnn Survey of FTP MAIL and MLFL
PARC-MAXC2 450 No such mailbox at this site. RADC-XPER 450 User Unknown RADC-MULTICS 450 Cannot locate mailbox for \Fzorkness\ RADC-TOPS20 450 No such mailbox at this site. RAND-UNIX 450 User Unknown RUTGERS 450 No such mailbox at this site. SDAC-UNIX 450 User Unknown SRI-KA 450 No such mailbox at this site. SRI-KL 450 No such mailbox at this site. SU-AI 450 I don't know anybody named Fzorkness SUMEX-AIM 450 No such mailbox at this site. UCLA-ATS 450 User Unknown UCLA-SECURITY 450 User Unknown UTEXAS 450 User Unknown
AMES-67 503 COMMAND \MAIL FZORKNESS\ IGNORED: UNKNOWN USER
LBL 506 Command not implemented.
CMU-10A 507 % USER NOT FOUND: FZORKNESS CMU-10B 507 % USER NOT FOUND: FZORKNESS CMU-10D 507 % USER NOT FOUND: FZORKNESS HARV-10 507 No such user as FZORKNESS LLL-MFE 507 No such user as FZORKNESS NBS-10 507 No such user as FZORKNESS WHARTON 507 No such user as FZORKN WPAFB-AFAL 507 No such user as FZORKNESS
4) Sites to which I was never able to connect, or which were not accepting users.