I'm going to answer my own message. I was afraid I shot Ejay down too
quickly. ;-] One remaining question is whether receiving a broadcast in an
unsupported frame format causes a CPU interrupt. I said it would because I
know that was the case with some implementations I worked on, but that was
a long time ago. The real answer is that it depends on the Ethernet chip
set, the driver software, and the operating system. The driver tells the
Ethernet chip set which frame formats (and which multicasts) to listen to.
A smart chip set would not pass anything else up. But, my experience has
been that chip sets aren't smart. They pass unsupported frame types and
some chip sets even pass multicasts for which the host is not registered.
The definite answer is that the broadcast would disturb the station
(counting the NIC as part of the station). To avoid that, you would have to
move the station to a different physical broadcast domain (other side of a
router) or different virtual broadcast domain (VLAN).
Priscilla
At 05:58 PM 7/12/01, Priscilla Oppenheimer wrote:
>At 04:29 PM 7/12/01, Hire, Ejay wrote:
> >Perhaps I was unclear by my meaning.
> >A station running Ethernet II that receives a ethernet_Snap frame discards
> >it. It is unintelligible.
>
>The broadcast generates an interrupt though. Broadcast domains are not
>relevant to the question. Get them out of your head. ;-) The only things
>that can stop broadcasts are routers and VLANs. It has nothing to do with
>frame types.
>
>
> >This is was what I meant by being in separate broadcast domains. A router
> >or server advertising services to more than one frame type has to
generate a
> >separate advertisement broadcast for every frame type, thusly It is
> >reasonable to say that each frame type creates a separate broadcast
domain.
> >(Same wire, separate domains.)
>
>That's not what is normally meant by a broadcast domain.
>
>Any station on the same switched or repeated network hears each of the
>broadcasts. If the device were on the other side of a router or in a
>different VLAN, it wouldn't hear them. The device would be in a different
>broadcast domain.
>
>
> >The question is rather blurry though. If it truly is a separate broadcast
> >domains, then the NIC should discard the frame without generating an
> >interrupt. If it passes it to the o/s to discard, then I'm not sure what
it
> >is?!
> >
> >IMHO, fwiw
> >-Ejay
> >
> >-----Original Message-----
> >From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]]
> >Sent: Thursday, July 12, 2001 12:56 PM
> >To: [EMAIL PROTECTED]
> >Subject: RE: IPX Network addresses [7:11990]
> >
> >
> >Yes, each frame type is associated with a different network number. They
> >are not different representations of the same network number. They are
> >different networks.
> >
> >Broadcast domains have nothing to do with it. If all devices in these four
> >networks are connected via hubs or switches, they see each other's
> >broadcasts. They process the broadcasts at the data-link-layer and only
> >process them further if they are running the same Ethernet frame type.
> >
> >If these are really internal network numbers, then the question is moot.
> >Internal network numbers don't need a frame type!?
> >
> >Priscilla
> >
> >At 10:46 AM 7/12/01, Hire, Ejay wrote:
> > >Each different frame type acts as a separate broadcast domain, thus they
> > >have different network numbers.
> > >
> > >-----Original Message-----
> > >From: Elmer Deloso [mailto:[EMAIL PROTECTED]]
> > >Sent: Thursday, July 12, 2001 8:41 AM
> > >To: [EMAIL PROTECTED]
> > >Subject: RE: IPX Network addresses [7:11990]
> > >
> > >
> > >Thanks for all the responses. This is the only IPX speaking box on the
>wire
> > >and the first NW5.1 server to be brought up. I understand that it
supports
> > >and automatically loads all IPX frame types by default if IPX is chosen
> > >along with the default and preferred IP protocol. From the replies it
>seems
> > >that each frame type would belong to a DIFFERENT IPX network? Or is it
>just
> > >DIFFERENT WAYS of writing out IPX network addresses depending on the
frame
> > >type used?
> > >Again, thanks for the enlightenment.
> > >
> > >Elmer
> > >
> > >-----Original Message-----
> > >From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]]
> > >Sent: Wednesday, July 11, 2001 4:29 PM
> > >To: [EMAIL PROTECTED]
> > >Subject: RE: IPX Network addresses [7:11990]
> > >
> > >
> > >Interesting. Why would it generate network numbers, though? Shouldn't
> > >network numbers be manually configured?
> > >
> > >Priscilla
> > >
> > >At 04:11 PM 7/11/01, Patricia Leeb-Hart wrote:
> > > >I finally feel qualified to comment on a question on this list (having
> > > >worked with NetWare for the past 6 years)
> > > >
> > > >The addresses you're seeing are generated automatically. What's
> >happening
> > > >here is that the new server has every single Ethernet frame type
loaded,
> > >and
> > > >as a result is using different IPX network number for every frame
type.
> > >New
> > > >3.x and 4.x servers will do this if you perform an install using all
the
> > > >defaults. You need to run INSTALL (or NWCONFIG if 5.x), edit the
> > > >AUTOEXEC.NCF and remove all BIND statements referencing frame types
you
> > > >don't want to use. Ethernet_II is preferred.
> > > >
> > > >NetWare 5.x is more restrained and tries to use IP only.
> > > >
> > > > >>> "Ayers, Michael" 07/11/01 12:12PM >>>
> > > >Those were either auto generated, or picked up from reading frames on
>the
> > > >wire.
> > > >
> > > >
> > > >-----Original Message-----
> > > >From: Elmer Deloso [mailto:[EMAIL PROTECTED]]
> > > >Sent: Wednesday, July 11, 2001 11:31 AM
> > > >To: [EMAIL PROTECTED]
> > > >Subject: IPX Network addresses [7:11990]
> > > >
> > > >hi, group.
> > > >I just noticed that after installing NetWare server, it gave me this
>info
> > > >regarding types of IPX frames:
> > > >Frame type Network address
> > > >Ethernet_802.2 3D410DCD
> > > >Ethernet_802.3 1E0F4F9E
> > > >Ethernet_SNAP FF994BB0
> > > >Ethernet_II D393B805
> > > >
> > > >For the IPX gurus in the group, can someone tell me if there is some
>type
> > >of
> > > >logic as to how the network address is translated from the type of
frame
> > > >used?
> > > >Just to answer my curiosity.
> > > >Thank you.
> > >________________________
> > >
> > >Priscilla Oppenheimer
> > >http://www.priscilla.com
> >________________________
> >
> >Priscilla Oppenheimer
> >http://www.priscilla.com
>________________________
>
>Priscilla Oppenheimer
>http://www.priscilla.com
________________________
Priscilla Oppenheimer
http://www.priscilla.com
Message Posted at:
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