Installation guide

21707112-001
5. TN3270 Client Definition Panel
The TN3270 Client Definition panel is used to map LINCS 3270 host resources to TN3270
clients. Through configuration of this panel, it is possible to assign specific LUs to a client, or
give LUs from a pool (3270 Host Class), or display a connection menu to the client. It is also
possible to determine whether a password is required by a client to gain access.
Specific LUs can be assigned using four different methods:
1. You can have a separate entry on this panel for each client, using the client’s IP
address to determine which resource is assigned to them. (This of course will not
work in DHCP environments.)
2. You can use a different TCP port for each client, so that depending on which
port is used to connect to the SCON-3074, only a specific session assignment is
given out.
3. The client can request the SCON-3074 resource at connection time using the format
“00,06” to request session “06” on host circuit “00”. This method can be prohibited
by enabling one of the RPQ options.
4. A nickname file can be set up to associate a requested resource name to a specific
SCON-3074 resource.
TN3287 clients typically request their own LU at connection time as an extension of the
Device Type field. As an example, the client would request the following device type
IBM-3287-1@01,16 where the device type is IBM-3287-1 and the extension @01,16 indicates
that host circuit 01, LU 16 (hex) is desired. When requesting specific LUs in this fashion, no
specific entry in the TN3270 Client Definition Panel is required. The LU requested, however
should be defined as part of a 3270 Host Class, set aside for specific LUs that will be requested
by TN3270 clients.
If a client requests a specific LU at connection time, the request takes precedence over what
is configured, unless one of the RPQ options is enabled to limit connections to those configured,
or to ignore all LU requests.
Requests that include invalid information such as a host or class that does not exist will result
in a failed connection attempt.
When attempting to match a resource to a client connection request, the SCON-3074 will
search the configured options based on the order in which they are defined on this panel.
Therefore, if the first entry for a user connecting on port 23 happens to be to get a session
from a pool, then it does not matter that a specific LU assignment was defined further down
the panel, they would get the pooled session instead. For this reason, it is good practice to
define specific LU assignments earlier in the table than pooled resource assignments.
Likewise, when using a nickname file to assign resources the nickname file is searched from
the beginning until the first match is found.
Note that you can have more TN3270 Client Definitions than the number of TN3270 Sessions
specified on the TCP/IP Line Options panel for a specific network interface. The number
configured for a specific line however, will limit the number of concurrent connections.