Browse Prior Art Database

Telnet logout option (RFC0727)

IP.com Disclosure Number: IPCOM000003773D
Original Publication Date: 1977-Apr-27
Included in the Prior Art Database: 2000-Sep-13
Document File: 3 page(s) / 5K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

M.R. Crispin: AUTHOR

Abstract

1. Command name and code.

This text was extracted from a ASCII Text document.
This is the abbreviated version, containing approximately 54% of the total text.

NWG/RFC# 727 MRC 26-APR-77 18:24 40025

Telnet Logout Option

Network Working Group Mark Crispin

Request for Comments 727 MIT-AI

NIC 40025 27 April 1977

TELNET Logout Option

1. Command name and code.

LOGOUT 18

2. Command meanings.

IAC WILL LOGOUT

The sender of this command REQUESTS permission to, or confirms

that it will, forcibly log off the user process at its end.

IAC WON'T LOGOUT

The sender of this command REFUSES to forcibly log off the user

process at its end.

IAC DO LOGOUT

The sender of this command REQUESTS that the receiver forcibly log

off the user process at the receiver's end, or confirms that the

receiver has its permission to do so.

IAC DON'T LOGOUT

The sender of this command DEMANDS that the receiver not forcibly

log off the user process at the receiver's end.

3. Default.

WON'T LOGOUT

DON'T LOGOUT

i.e., no forcible logging off of the server's user process.

4. Motivation for the option.

Often, a runaway user process could be hung in such a state that it

cannot be interrupted by normal means. Conversely, the system itself

could be bottlenecked so that response delays are intolerable. A

user (human or otherwise) eventually will time out out of frustration

NWG/RFC# 727 MRC 26-APR-77 18:24 40025

Telnet Logout Option

and take the drastic means of closing the connection to free itself

from the hung process. In some situations, even the simple operation

of logging out can take a long time.

Some systems treat a close to mean that it should log out its user

process under it. However, many hosts merely "detach" the process so

that an accidental close due to a user or temporary hardware error

will not cause all work done on that job to be lost; when the

connection is re-established, the user may "attach" back to its

process. While this protection is often valuable, if the user is

giving up completely on the host, it can cause this hung job to

continue to load the system.

This option allows a process to instruct the server that the user

process at the server's end should be forcibly logged out instead of

detached. A secondary usage of this option might be for a server to

warn of impending auto-logout of its user process due to inactivity.

5. Description of the option.

When a user decides that it no longer wants its process on the server

host and decides that it does not want to wait until the host's

normal log out protocol has been gone through, it sends IAC DO

LOGOUT. The receiver of the command may respond with IAC WILL

LOGOUT, in which case it will then forcibly log off the user process

at its end. If it responds with IAC WON'T LOGOUT, then it indicates

that it has not logged off the user process at ...