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Encapsulating SNA/SDLC Traffic in TN3270e transmission

I have a Cisco 2811 router connected via T-1 to another 2811 router which is connected via Intranet to an IBM Mainframe running an IBM TN3270 protocol stack. I can communicate easily over the link utilizing a PC running a TN3270 application on it.

What I need to do is connect the 9600 baud line from my IBM controller (usually runs to a serial modem) to a WIC-2T= card via an RS232 to RTE 60 cable. Once this is achieved I need to configure the router to encapsulate the 3278 sessions from the controller into TN3270 packets over the T-1 to the IBM Mainframe.

Does anyone has a sample configuration that I can utilize as a model? I will need to take the TN3270 responses from the mainframe and convert them back into 3278 transmissions as well.

Will I need to purchase additional software or can I download it off the Cisco site? If so, what is the name of the product to download?

I would really appreaciate any help that can be provided.


Re: Encapsulating SNA/SDLC Traffic in TN3270e transmission

The following example establishes a terminal session with an IBM TN3270 host named finance and specifies vt100 as the terminal type:" Router> tn3270 finance /terminal-type vt100". Refer the following URL for complete TN3270 configuration


Re: Encapsulating SNA/SDLC Traffic in TN3270e transmission

What you want to do is called STUN or BSTUN. Depending upon the protocol that your controller is using. If Bisync then BSTUN , if SNA then STUN. These methods encapsulate the IBM protocols into IP. However keep in mind that on the mainframe side you need to unencapsulate them. How are you talking to the mainframe? Via OSA, 3172, FEP, TIC? Cisco offers many solutions to STUN and BSTUN.

Re: Encapsulating SNA/SDLC Traffic in TN3270e transmission


actully here what you want exactly are going to have async or sync data which is not routed by the router so you have to conver the sync/async data into the small TCP/IP packet and then only you can able to make it travel through IP network... for that you can have the BSTUN configuration... in this process router store the async data in to its buffer and algoritm make small packet of TCP/IP... i had configure such project for one of our client... and you can get the good configuration example on this link:

hope this will help you

remeber to rate this post if it helps



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