IBM 3174 C 6.4 Microcode Disks?

Ken Seefried seefriek at
Wed Feb 20 15:09:46 CST 2019

On Wed, Feb 20, 2019 at 2:23 PM Paul Koning <paulkoning at> wrote:
> > On Feb 20, 2019, at 2:13 PM, Ken Seefried via cctalk <cctalk at> wrote:
> >
> > ...
> > You can bridge between TR (and FDDI) and ethernet on a Cisco,
> > generally for non-routable protocols (e.g. NetBIOS); see:
> > 'translational bridging'.  If you're trying to get these protocols
> > across an intermediary 'alien' network (like the corp FDDI backbone,
> > or the Internet), there are things like DLSw.
> Please note that among LANs, there is Token Ring (802.5) and there is everything else.  FDDI is like Ethernet and like 802.4.  Token Ring is the oddball because (a) it doesn't have proper multicast addresses, and (b) for some reason IBM invented source-routed bridging and tied that to Token Ring.
> FDDI is in no way at all like Token Ring.  The only thing the two have in common is "token" and "ring".  The MAC protocol is utterly different; the closest relative is 802.4 Token Bus.  And as far as addressing is concerned, FDDI is like 802.4 and Ethernet, with real multicast and general use of normal transparent bridges.

I didn't say TR was like FDDI.  I said you could bridge FDDI to
Ethernet using translation bridging.

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