HP-UX SNAplus2 General Information (October 1998)

36 Chapter 2

Introducing SNAplus2

SNAplus2 Resources

computers connected to SNAplus2 over a local token ring network, so

that they all access the same long-distance SDLC leased line from

SNAplus2 to the host.

Using PU concentration also simpliﬁes the conﬁguration at the host,

because there is no need to deﬁne the downstream computers and the

communications links to them. The host conﬁguration needs to include

only the SNAplus2 computer and its host communications link; the LUs

at the downstream computers are conﬁgured as part of the resources of

the SNAplus2 computer. The host computer is not aware that PU

concentration is being used.

TN Server

3270 emulation programs that communicate over TCP/IP (rather than

over an SNA network) are referred to as “TN3270 programs” (Telnet

3270 emulation programs).

TN3270 programs can also include support for TN3270E (Telnet 3270

standard extensions). TN3270E supports 3270 device emulation

(including both terminals and printers) using Telnet. It enables a Telnet

client to select a particular device (by specifying the LU name), and

provides enhanced support for various functions, including the ATTN

and SYSREQ keys and SNA response handling.

NOTE This book uses the term TN3270 to refer to information that applies

equally to the TN3270 and TN3270E protocols.

SNAplus2 TN server provides access to 3270 host computers for TN3270

users on other computers. TN server enables TN3270 users to share a

host connection with SNAplus2 or with other TN3270 users, instead of

requiring a direct link. TN server also enables TN3270 users to access

hosts that are not running TCP/IP.