Thinwire to UTP



  • Hi everyone. My first post.

    I've been looking around for some time now for a 10base2 to 10baseT media converter. I've not had any success given the vintage of 10base2. I got to thinking though that maybe what I need is a router with BNC and UTP interfaces. Here's some background leading up to my current thoughts.

    I'm trying to resurrect several VAX machines that have been sitting in my garage for the last 15 years. It's been on my bucket list forever. I can daisy-chain the VAXen using thinwire, but at some point, I'd like to integrate this arrangement back into my home network.

    My initial thoughts were to get a pair of PCI network cards; one with a BNC port (still available on e-bay), the other with a UTP port, and bridge these together using a 32-bit Windows system such as XP or Vista. But then I thought, the native VMS protocols are DECnet and LAT and I didn't want these protocols flooding over to my IP network, so bridging is probably not a good idea.

    My journey has brought me to pfsense. I could still build a box, which is essentially a media converter between thinwire and standard ethernet, but have a separate subnet for the thinwire devices. pfsense would provide the glue that holds everything together. LAT is a non-routable, broadcast protocol so it won't pass over to the home network. DECnet, on the other hand, is routable.

    My questions at this stage are:

    1. Will pfsense fill the bill as a router? I keep seeing posts that pfsense is more of a firewall. Hence the question.
    2. If pfsense is the right way to go, can it be set up to do selective protocol routing? I'd like IP to be on both sides of the pfsense router, but DECnet and LAT contained to the thinwire side of the network.

    Any advice, reassurance or suggestions will be most welcome and appreciated.


  • Netgate

    Any router will keep your broadcast domains isolated, pfSense included.

    pfSense will not forward DECnet or LAT, since it is an IP firewall.



  • @derelict Sounds like pfsense fits the bill perfectly. Thank you for the feedback.


  • Galactic Empire

    pfSense doesn't support DECnet or LAT, look at an old Cisco on ebay with AUI & ethernet interfaces.

    https://en.wikipedia.org/wiki/Attachment_Unit_Interface

    A Cisco 2514 would probally do it, if you can find the adaptors for 10BaseT & 10Base2.

    https://www.ebay.co.uk/itm/Cisco-2500-Series-Model-2514-Dual-Serial-Ethernet-Token-Ring-Router/362248696857?epid=1104448365&hash=item5457b47419:g:ZTMAAMXQtRxSJLoe



  • @nogbadthebad I actually don't need pfsense to support DECnet or LAT. As long as those protocols are kept to the thinnet side of the router, as @Derelict has suggested, it should work admirably.


  • Galactic Empire

    @basilh said in Thinwire to UTP:

    @nogbadthebad I actually don't need pfsense to support DECnet or LAT. As long as those protocols are kept to the thinnet side of the router, as @Derelict has suggested, it should work admirably.

    Think you'll struggle to find a 10Base2 PCIE card, have a look here for supported cards:-

    http://www.si.freebsd.org/relnotes/CURRENT/hardware/support.html



  • @nogbadthebad Haven't seen any PCIE on offer, but there's a 3Com PCI combo card that several sellers seem to be offering on ebay and tons of ISA cards. However, it's rare to find a motherboard that supports ISA so those cards are next to useless. I still have a motherboard that has PCI slots so there's a match there for me. Are there going to be any issues with drivers for pfsense? The card model is 3COM PCI 3C5900-COMBO ETHERLINK XL - RJ45 - AUI - BNC Card 03-0108-002 REV A.


  • Netgate

    I would personally look for an old ethernet hub with a 10Base2 port instead of a card. That way you can use a reasonably-modern NIC and let the old hub talk to the old gear.



  • You could use a 10 Mb hub. Many of them had a BNC connector. I have one of those hubs here. However, I don't understand why you'd use pfSense for this, as mentioned above, it doesn't support DecNET.


  • Netgate

    lol. beat you by like a second.


  • Galactic Empire

    @basilh said in Thinwire to UTP:

    @nogbadthebad Haven't seen any PCIE on offer, but there's a 3Com PCI combo card that several sellers seem to be offering on ebay and tons of ISA cards. However, it's rare to find a motherboard that supports ISA so those cards are next to useless. I still have a motherboard that has PCI slots so there's a match there for me. Are there going to be any issues with drivers for pfsense? The card model is 3COM PCI 3C5900-COMBO ETHERLINK XL - RJ45 - AUI - BNC Card 03-0108-002 REV A.

    You'd need to check the link I supplied, pfSense is based on FreeBSD.



  • @Derelict @JKnott Am I missing something? As long as DECnet is isolated to the thinwire side, pfsense doesn't need to support it. I looked high and low for a hub with a bnc port and lucked out. Besides, a hub would allow both LAT and DECnet to flood the home network which is what I'm trying to avoid. If I need to play around with LAT or DECnet, I'll do so on the thinwire side, otherwise from the home network, I'll access a VAX using IP.


  • Netgate

    Yes, you are missing something.

    Use a hub to bridge from the thinwire to 10BaseT. Connect 10BaseT to a modern NIC in pfSense. That way you don't have to try to get some old-ass card working in pfSense.

    From a broadcast domain perspective nothing changes.



  • @derelict Ahh. Gotcha. Good point. I'll have another look for a suitable hub.



  • @nogbadthebad Thanks for the link. Have confirmed the BNC NIC I was interested in is not supported.



  • @Derelict @JKnott Thanks guys for setting me on the straight and narrow. I'll now hunt down a hub with a BNC port instead of BNC NIC, and I still get to use pfsense :)