I need to build a connection between a new Tandem that speaks only
Bisync, as we configured it, to an IBM that speaks only Ethernet. The
Tandem does not speak the "EP" flavor of Bisync, but the NCP or VTAM
flavor, which is called Polled Bisync. The IBM speaks only Ethernet because
we did not purchase a 3745 controller, and do not wish to purchase one.
Third-party vendors are offering solutions, but they seem too bulky and
expensive. The circuit could look like this:
Tandem <--- BSC/LLC------------LLC/BSC<----IBM
"BSC/LLC" means Bisynchronous over Logical Link Control. In this example
Bisynchronous would be encapsulated or tunnelled in LLC. I know I said
the IBM could speak only Ethernet, but if we could find a solution for
Polled Bisync on the IBM side, that also might be helpful. We are wondering
about using two boxes, one that does BSC/LLC on the Tandem side, and
one that does LLC/BSC on the IBM side. We're also wondering if we can
use something as simple as one router and one cable. The circuit sketch
has arrows pointing left because the IBM must be the source or primary
in the data communications. The Tandem watches for a polling number from
the IBM, and when it sees the correct one, sends a message to the IBM.
