Hi,

Just to expand on this... 

The 224.0.0.1 multicast query you're seeing is coming
from the cable modem I bet. I have a Surfboard 3100
cable modem and it sends out IGMP queries on 224.0.0.1
frequently. I'm not sure why the cable modem is doing
multicast and haven't really looked into it. I think
it may only be local to the LAN interface toward your
PC but not 100% positive. You can use your web browser
to view the log and status of the SB3100 cable modem
by the way, you can see the IP in the sniffer trace. 

If the ARP requests are originating from the ISP
default-gateway (first hop router for you) then maybe
they have proxy arp enabled. 

The DHCP requests could be from other users on your
segment, or maybe forwarded to a DHCP server on your
segment from another segment. 

Also, since you're on a shared segment with others
they may have set up their own networks, etc with
their own address space, etc that you might see
packets from. 

Erick

--- Priscilla Oppenheimer  wrote:
> It sounds like you are sharing the broadcast domain
> with a bunch of other 
> stations. The network is bridging on the edge. I
> think this is normal for 
> cable modem systems. Is that what you are on?
> 
> Priscilla
> 
> At 12:23 PM 1/2/02, Phil Barker wrote:
> >Hi Group,
> >      I have been sniffing my broadband connection
> to
> >my ISP today and have a few questions.
> >
> >      My main gripe is that I'm being sent around
> 100
> >Arp requests per minute, which obviously I cannot
> >resolve. These ARP requests are all originating
> from
> >my default G/W at the ISP trying to resolve MAC
> >addresses of various users. Can anyone confirm if
> this
> >is usual or unusual. I cannot see this being
> correct
> >since if I set my router up to be one of these IP
> >addresses I can resolve it to my MAC address Eth 0
> >int' or any other mac-address for that matter.
> >
> >      They also send me DHCP requests, IGMP
> requests
> >for group 224.0.0.1 (Which I wish I could join) but
> >cannot and lots of their private address
> information
> >via the above mentioned ARP's.
> >
> >      I also captured an attemt at an inbound TCP
> >connection on a dynamic port which my router RST,
> >thankfully.
> >
> >      Are they wasting my B/W ?
> >
> >Thanx,
> >
> >Phil
> >
> >
> >
> >
> >
> >__________________________________________________
> >Do You Yahoo!?
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> ________________________
> 
> Priscilla Oppenheimer
> http://www.priscilla.com
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