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New Member

Query on DLSw, STUN and BSTUN

Here are my queries -

1.Could the tunneling protocols...DLSw, STUN , BSTUN

be used to tunnel just any protocol, or is it specific to IBM SNA , NetBIOS?

we are interested in connecting NCR mainframe systems over IP.These NCR systems talk NCR proprietary protocol, and connect by a Serial Async interface.

2. Assuming that the tunneling protocol can tunnel

even the NCR proprietary protocol (like it does SNA),

should only STUN / BSTUN be used since a serial

interface is involved...and not DLSw which would run

only with Ethernet / token ring in the LAN ?

If someone has worked on this..or has any idea on how

things work...please do let me know.

Thanks in advance,


Cisco Employee

Re: Query on DLSw, STUN and BSTUN


the question is what exactly is the protocol you are talking about?

We do have some support for async generic in bstun.

Stun basic transports virtualy everything but it needs a synchron protocol, basicaly 7E's to identify the start of frame and end of frame. It does not deal with async protocols.

Dlsw does only do sdlc and qllc on the serial

connected interfaces.

I would advice to open a case with cisco tac, the ibm team, please mention you want to use bstun to tunnel a async protocol, and then determine what exact protocol you are dealing with. Based on the outcome of this we can determine futher if there is support for this protocol or not.

New Member

Re: Query on DLSw, STUN and BSTUN

Thanks for that.

I needed to know if DLSw was tunneling protocol specific to IBM SNA. Looks like it is.

So now, like you said I would need to find out the protocol which NCR Mainframe (which need to be connected in my set up) talk.

Thanks again.


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