Cisco Systems 11.0 BT Server User Manual


 
Configuring TN3270 Server on the Channel Interface Processor 7
Configuring TN3270 on a Channel Interface Processor
IBM-DYNAMIC: This willresult in “DYNAMIC” being putin the modeltype and numberfield.
The VTAM configurationwill need tohave “DYNAMIC” defined as atemplate in theLU group.
In fact “IBM-ZZ..Z,” where “ZZ..Z” does not match the preceding syntax, will be forwarded as
“ZZ..Z.”
Note The “E” in the model string refers to 3270 extended datastream. It has no connection with
the “E” in “TN3270E”.
Any other string is forwarded as is.
In all cases, the string forwarded is translated from ASCII to EBCDIC and truncated at seven
characters.
A complication arises with TN3270E clients thatrequest a copy of the BIND-IMAGE. Such clients
require system control services (SCS) datastream on the system services control point (SSCP)-LU
flow. All other clients require 3270 datastream on that flow. Therefore, these two kinds of client
must be directed to different LUGROUP entries at the host. To make this as easy as possible, the
SCS requirement is also encoded into the model string sent to the host. Following the previously
described terminal type string formats accepted by the server, this additional condition is applied:
If the client has negotiated to receive BIND-IMAGE, the character “S” is overlaid on the fifth
character of the string, or appended if the string is less than five characters. (See Table 3.)
Specific LU Allocation
A TN3270E client can request a specific LU name by using the TN3270E command CONNECT as
documented in RFC 1647. The name requested must match the name by which the TN3270 server
knows theLU (see the section“LU Names in theTN3270 Server”), andthe host must have activated
the LU (with ACTLU).
LU Names in the TN3270 Server
Where SNA session switching is configured (that is, on DLUR PUs) the TN3270 server learns the
LU names from the ACTLUs.
For direct PUs, a “seed” name can be configured on the PU. The TN3270 server uses this name in
conjunction with the LOCADDRS to generate names for the LUs. It is best to use the same naming
convention as the host, if possible.
Table 3 Examples of Model String Mapping
String from client (ASCII)
BIND-IMAGE
requested? String to Host (EBCDIC)
IBM-3278-4 No 327804
IBM-3279-5E No 327905E
IBM-3279-3-E Yes 3279S5E
IBM-DYNAMIC Yes DYNASIC
ABC Yes ABCS
ABCDEFGH Yes ABCDSFG