|
Posted by km@mathcs.emory.edu on May 1, 2007, 9:18 am
If you were Registered and logged in, you could reply and use other advanced thread options
I want to use an ethernet hub, and be able to "snoop" the traffic on
one of its ports. This used to be trivial before all hubs were really
switches.
Its really amazing how cheap a desktop mulitport 100mbit switch is.
But I don't know of one that will let me snoop traffic for debugging.
We do have an "expensive" managed HP rack mount switch which lets you
designate one port to mirror the traffic on a designated set of other
ports. However, for the desktop application, I don't need any of the
other "managed" features, or even the flexibility of that mirroring,
and want something much less expensive.
Actually, I would be happy with a physical "1 to 2" port dongle, that
I could plug into an existing port and use to monitor the traffic on
that port.
|
 
| |
Posted by Al Dykes on May 1, 2007, 9:31 am
If you were Registered and logged in, you could reply and use other advanced thread options
>I want to use an ethernet hub, and be able to "snoop" the traffic on
>one of its ports. This used to be trivial before all hubs were really
>switches.
>
>Its really amazing how cheap a desktop mulitport 100mbit switch is.
>But I don't know of one that will let me snoop traffic for debugging.
>
>We do have an "expensive" managed HP rack mount switch which lets you
>designate one port to mirror the traffic on a designated set of other
>ports. However, for the desktop application, I don't need any of the
>other "managed" features, or even the flexibility of that mirroring,
>and want something much less expensive.
>
>Actually, I would be happy with a physical "1 to 2" port dongle, that
>I could plug into an existing port and use to monitor the traffic on
>that port.
>
Look on ebay for a 4 port hub. That's where I got mine.
I've heard that vendors have been knwon to use the words
interchangable and an Ebay sellor is likely to miss-describe the item,
so it's kind of a crapshoot. They will be *very* cheap, so yo might
have to buy a couple.
The dongle won't work.
--
a d y k e s @ p a n i x . c o m
Don't blame me. I voted for Gore. A Proud signature since 2001
|
|
Posted by stephen on May 2, 2007, 5:33 pm
If you were Registered and logged in, you could reply and use other advanced thread options
> >I want to use an ethernet hub, and be able to "snoop" the traffic on
> >one of its ports. This used to be trivial before all hubs were really
> >switches.
> >
> >Its really amazing how cheap a desktop mulitport 100mbit switch is.
> >But I don't know of one that will let me snoop traffic for debugging.
> >
> >We do have an "expensive" managed HP rack mount switch which lets you
> >designate one port to mirror the traffic on a designated set of other
> >ports. However, for the desktop application, I don't need any of the
> >other "managed" features, or even the flexibility of that mirroring,
> >and want something much less expensive.
> >
> >Actually, I would be happy with a physical "1 to 2" port dongle, that
> >I could plug into an existing port and use to monitor the traffic on
> >that port.
> >
>
>
> Look on ebay for a 4 port hub. That's where I got mine.
>
> I've heard that vendors have been knwon to use the words
> interchangable and an Ebay sellor is likely to miss-describe the item,
> so it's kind of a crapshoot. They will be *very* cheap, so yo might
> have to buy a couple.
find one where the description gives the manufacturer and p/n, then check on
the web site for exactly what it is.
to start you off i have a Netgear dual speed hub, type DS116 - 16 ports of
10/100.
this is 2 hubs, 1 @ 10M and 1 @ 100, with a switch linking them, so a 10/100
device can connect.
as long as all device attach at the same speed, it acts like a simple hub at
10 or 100.
and no - i got it for the same reason, so it isnt for sale.
>
> The dongle won't work.
>
>
> --
> a d y k e s @ p a n i x . c o m
> Don't blame me. I voted for Gore. A Proud signature since 2001
--
Regards
stephen_hope@xyzworld.com - replace xyz with ntl
|
|
Posted by Kevin on May 3, 2007, 3:39 am
If you were Registered and logged in, you could reply and use other advanced thread options
km@mathcs.emory.edu wrote:
> I want to use an ethernet hub, and be able to "snoop" the traffic on
> one of its ports. This used to be trivial before all hubs were really
> switches.
>
> Its really amazing how cheap a desktop mulitport 100mbit switch is.
> But I don't know of one that will let me snoop traffic for debugging.
>
> We do have an "expensive" managed HP rack mount switch which lets you
> designate one port to mirror the traffic on a designated set of other
> ports. However, for the desktop application, I don't need any of the
> other "managed" features, or even the flexibility of that mirroring,
> and want something much less expensive.
>
> Actually, I would be happy with a physical "1 to 2" port dongle, that
> I could plug into an existing port and use to monitor the traffic on
> that port.
>
You need to make sure you get a repeater. As others have said,
manufacturers sometimes call products "hubs" which are actually
switches. Problem is very few chipset vendors still makes repeating
silicon - all the volume moved to switching more than 5 years ago.
If you just want 10M repeating, take a look at 3C16700A from 3Com - 8
port repeater. Also from them is 3C16755 which is a 5 port 10/100
repeater with a switch to connect the 10M and 100M collision domains.
Both are around $60. Clearly you can buy a small switch for less than
half this, but that isn't going to help ;-)
Note that I expect most repeaters to be EOL within the next 12 months as
none of the current silicon that I am aware of is RoHS compliant, so it
can't be shipped to any regions requiring this complaince.
|
|
Posted by glen herrmannsfeldt on May 3, 2007, 3:47 am
If you were Registered and logged in, you could reply and use other advanced thread options
km@mathcs.emory.edu wrote:
> I want to use an ethernet hub, and be able to "snoop" the traffic on
> one of its ports. This used to be trivial before all hubs were really
> switches.
(snip)
> Actually, I would be happy with a physical "1 to 2" port dongle, that
> I could plug into an existing port and use to monitor the traffic on
> that port.
If you can remove the terminating resistor on a dongle
receive port, it should be possible to connect it to a pair
in the middle of a cable, such that the cable can be used
to pass traffic. You won't be using the transmit port
for snooping, so don't even connect that.
I don't know which dongles, if any, have a terminating resistor
that can be removed. On newer ones, it is likely surface mount,
and maybe also be on older ones. That makes is a little harder
to remove, but it should still be possible.
-- glen
|
| Similar Threads | Posted | | Monitor traffic through router? | October 13, 2007, 1:46 pm |
| Netgear FVS 318 Wan Port to Ethernet Port on Alvarion ITU Problems... | January 20, 2006, 4:55 am |
| Looking for low cost Ethernet split switch | June 14, 2007, 10:05 pm |
| Cost for Gigabit Ethernet or 2 Gbit Fibre Channel Circuits | April 27, 2006, 3:52 am |
| difference b/w inter-switch link port and trunk port | July 6, 2008, 12:06 pm |
| Seeing Packets on an Ethernet Port That Should Not Be There | October 4, 2007, 11:54 pm |
| CAT-5 cable stuck in ethernet port - can't remove | April 26, 2006, 5:55 am |
| Safe.com 8 Port 10/100Mbs Fast Ethernet Switch | February 13, 2005, 9:49 am |
| 10M full forced port connected to 100M full Duplex port | March 25, 2006, 1:49 am |
| Low-cost, high-quality design team | October 16, 2005, 2:05 pm |
|
|
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML site map