TN3270 Extensions for LUname and Printer Selection (RFC1646)
Original Publication Date: 1994-Jul-01
Included in the Prior Art Database: 2019-Feb-12
Internet Society Requests For Comment (RFCs)
C. Graves: AUTHOR [+2]
This document describes protocol extensions to TN3270. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
Network Working Group C. Graves Request for Comments: 1646 T. Butts Category: Informational M. Angel Open Connect Systems July 1994
TN3270 Extensions for LUname and Printer Selection
Status of this Memo
This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
This document describes protocol extensions to TN3270. There are two extensions outlined in this document. The first defines a way by which a TN3270 client can request a specific device (LUname) from a TN3270 server. The second extension specifies how a TN3270 printer device can be requested by a TN3270 client and the manner in which the 3270 printer status information can be sent to the TN3270 server. Discussions and suggestions for improvements to these enhancements should be sent to the TN3270E Working Group mailing list TN3270E@list.nih.gov . These extensions will be called TN3287 in this document. This information is being provided to members of the Internet community that want to support the 3287 data stream within the TELNET protocol.
The need to communicate with IBM mainframe systems has a number of unique requirements associated with it. This document addresses those needs in a TCP/IP communications network.
IBM terminals are generically referred to as 3270’s which includes a broad range of terminals and devices,not all of which actually begin with the numbers 327x.
The 3270 family of terminals and the IBM mainframe applications systems are VERY closely coupled and it is the nature of the way the 3270s and the applications interact which require that this document be available to provide a consistent way for the TCP/IP environment to interact effectively with the 3270 applications of the IBM mainframe world.
Graves, Butts & Angel [Page 1]
RFC 1646 TN3270 Extensions July 1994
IBM mainframe applications systems have existed for almost two decades now and are used to serve tens of thousands of users daily. For this reason it is usually the need of a mainframe environment to add TCP/IP network support WITHOUT writing new applications to run with the TCP network. The TN3270 series of documents addresses how this can be done and maintain compatibility with those mainframe application systems.
One of the unique characteristics of the 3270 terminals is their ability to communicate status information in an out-of-band data flow. These status’s are in turn used by the applications systems to support error recovery, and conflict resolutions, examples of these are printer out of paper, and terminal powered up. The terminals are also half duplex and block mode in their operations, which results in the need to communicate when blocks are being sent, when they end, and when they cannot be sent. This document describes these characteristics in IBM VTAM/SNA terms. Some VM mainframe application systems do not use VTAM, so for those systems these terms don’t apply. For an...