Scenario: SNA direct connection to a host system

 

This example shows a Systems Network Architecture (SNA) direct connection to a host system.

The following figure shows the configuration of a System i™ model for frame-relay communications with a 3745 host controller.

Figure 1. SNA direct connection to 3745 host controller

The 3745 host controller provides the frame-relay network function, and the System i model is configured as a terminal equipment (TE).

A 64000 bps V.35 line exists between the System i model and the 3745 host controller. The System i model might also have data link connection identifier (DLCI) connections to multiple 3745 host controllers, 6611 Network Processor, and RouteXpanders through the 3745 host controller. However, these configurations are not shown as part of this scenario.

There is a single permanent virtual circuit (PVC) connection between the System i model and the host system. This connection supports a 3270 emulation device that is used to access applications on the host. It also includes a distributed host command facility (DHCF) session.

Configuration for the System i model

Use the following commands to configure the System i model using an SNA direct connection with the 3745 host controller and the host system: 

CRTNWIFR   NWID(FR3745) RSRCNAME(LIN121) +
           INTERFACE(*V35)1 LINESPEED(64000)1 +
           LMIMODE(*TE)2 TEXT('Frame relay connection to 3745')

CRTLINFR   LIND(FR3745) NWI(FR3745) NWIDLCI(26) +
           EXCHID(05636759) TEXT('DLCI connection to the host')

CRCTCLHOST CTLD(FRHOST) LINKTYPE(*FR) APPN(*NO) +
           SWTLINLST(FR3745) MAXFRAME(8182) +
           SSCPID(050000000001) SWTDSC(*YES) +
           TEXT('Remote host system')

CRTDEVDSP  DEVD(FRDHCF) DEVCLS(*RMT) TYPE(3277) +
           MODEL(*DHCF) LOCADR(02) CTL(FRHOST) +
           TEXT('Remote host system dhcf device')

CRTDEVHOST DEVD(FREML) LOCADR(01) RMTLOCNAME(HOSTSYS) +
           CTL(FRHOST) APPTYPE(*EML) +
           TEXT('Emulation device to remote host')
Notes:

  1. The INTERFACE and LINESPEEED parameters must match the characteristics of the line to the 3745 host controller.

  2. The local management interface (LMI) mode is the default value of *TE, which means the System i model acts as the terminal equipment. You must configure the 3745 as the frame handler (FH) by using American National Standards Institute (ANSI) Annex D (DLCI 0).

  3. By creating a frame-relay line description (CRTLINFR), you indicate that the DLCI is connected to another device. The device supports the frame-relay SNA direct frame format of RFC 1490, such as the 3745 host controller.

  4. The DLCI for the line must match the DLCI that you assigned in the configuration of the 3745 host controller.

 

Parent topic:

Scenarios: SNA direct connection for frame relay