[mythtv-users] Enough power?

Matt Mossholder matt at mossholder.com
Tue Jan 18 20:44:15 EST 2005


Robert,
    The 10/100Mbit hubs are actually a marketing simplification in
naming ;) What they actually are, are a 10Mbit segment, and a 100Mbit
segment, with a switch in between them. When you plug in a device, the
device determines which segment to connect you to. When a 10Mbit device
talks to a 100Mbit device, it passes through the switch. I've also seen
some of these "hubs" that are actually full fledged switches. 

    Of course, this could be different, depending on the exact device
you have, but regardless of the device, there is no IEEE 802.3 spec that
allows Ethernet devices of different speeds to coexist on the same
physical segment. You can logically connect them via a switch or bridge.

        --Matt


On Tue, 2005-01-18 at 19:18 -0600, Robert Denier wrote:

> Everyone probably knows this, but just in case they don't..
> 
> Anytime you see a wireless speed you can probably cut it in half for the 
> actual speed you get.  Furthermore the more wireless clients you have on 
> a channel, even if they are not transmitting, the slower the network 
> operates, although its not a huge difference.  At leasts thats my 
> experience with 802.11b networks and the orinoco driver series.
> 
> One small point.  I've connected 10Mb devices to a cheap 10/100 hub and 
> everything works fine.  I don't know what its actually doing internally 
> of course.  Of course if your still using hubs and having bandwidth 
> issues, well switches were quite cheap last I looked.
> 
> As a final comment.  If your doing anything beyond web browsing.  (I.E. 
> mythtv or playing multimedia files over a network, then avoid 802.11b as 
> much as feasible.  It simply isn't fast enough to keep everything 
> responsive.  That doesn't mean you can't use it for those purposes where 
> you truly need it, but well sometimes the time you save not running a 
> cable, you lose later.  802.11g might solve those issues, but I've never 
> seriously tried to get it working under linux.)  (Netgear MA311 pci 
> cards with the orinico and/or hostap driver series are my 
> recommendations for linux for 802.11b.)
> 
> Matt Mossholder wrote:
> 
> > Brad,
> >     Just to clear something up... a 10Mbit client connected to a 
> > 100Mbit network does NOT "10x the bandwidth it is using, because it is 
> > time that matters." The only way to connect a 10Mbit client to a 
> > 100Mbit network is via a switch or bridge, which does rate conversion 
> > on each frame. Hench, a 10Mbit client's traffic will be converted to 
> > 100Mbit when the frame is sent out by the switch. The time in between 
> > the frames to/from the 10Mbit client is free for use by other systems.
> >
> >     Now, if we are talking about something like 802.11, that's a 
> > different story.... 802.11b clients definitely have a negative impact 
> > on the 802.11g traffic, when the b and g clients are both on the same 
> > channel. This is because everything is a broadcast, and in this 
> > instance, it really is the time that matters. The 802.11g clients 
> > can't talk or be talked to while the 802.11b systems are...speaking... 
> > so...slowly....
> >
> >     I agree with everything else though :)
> >
> >         --Matt
> >
> >
> 
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users

-- 
Matt Mossholder <matt at mossholder.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mythtv.org/pipermail/mythtv-users/attachments/20050118/e54a9e50/attachment.html


More information about the mythtv-users mailing list