6 Configuring TN3270 Server on the Channel Interface Processor
Configuring TN3270 on a Channel Interface Processor
Note To enable the TN3270 server feature, you must have a CIP installed in a Cisco 7000 family
router.The TN3270 server is different from the TN3270 terminal emulation access feature described
in the “Configuring TN3270” chapter of theAccess Services Configuration Guide.
Configuring TN3270 on a Channel Interface Processor
The following sections describe additional features of TN3270 server support on the CIP. The
features discussed include the following:
•Dynamic LU Allocation
•Formation of LU Model Type and Number
•Specific LU Allocation
•SNA Session Switch—End Node DLUR
•Multiple Hosts Support
You will also need to understand the following information before proceeding with TN3270
configuration tasks:
•VTAM Host Configuration Considerations for Dynamic LU Allocation
•TN3270 Configuration Modes
Dynamic LU Allocation
Thiswill be the most common form of request from TN3270 clients emulating a TN3270 terminal.
The user typically wants to specify emulating a particular terminal type and normally is not
interested in what LOCADDR or LU name is allocated by the host, as long as a network solicitor
logon menu is presented. The server will perform the following on such a session request:
•Form an EBCDIC string based on the model type and number requested by the client (see
“Formationof LU Model Type and Number” for the algorithm used). This string is used as a field
in a Reply product set ID (PSID) network management vector transport (NMVT).
•Allocate a LOCADDR from the next available LU in the generic LU pool. This LOCADDR is
used in the NMVT.
•Send the formatted Reply PSID NMVT to VTAM.
WhenVTAM receives the NMVT,it will use the EBCDIC model type and number string to look up
an LU template under the LUGROUP. For example, the string “327802E” will find a match in the
sample configuration shown in Figure2. An ACTLU will be sent and a terminal session with the
model and type requested by the client is established.
Formation of LU Model Type and Number
VTAMrequires a model type and number from the Reply PSID NMVT to use as a key to look up in
the LU group to find an LU template. The model type is a four character string; the model number
isa two or three character string. The server will accept the following formats of terminal type string
from the client:
•IBM-<XXXX>-<Y>[-E]: This will be formatted as “XXXX0Y”or “XXXX0YE” in the model
type and number field in the Reply PSID NMVT.