FW: [LINK] IPv4 host density measured by ping

[Daniel Rose]

> -----Original Message-----
> From: link-bounces at anumail0.anu.edu.au 
> [mailto:link-bounces at anumail0.anu.edu.au] On Behalf Of Adam Todd
> Posted At: Thursday, 1 March 2007 0:31 AM
> Posted To: Link List
> Conversation: [LINK] IPv4 host density measured by ping
> Subject: Re: [LINK] IPv4 host density measured by ping
> 
> 
> At 10:32 PM 28/02/2007, Robin Whittle wrote:
> >I couldn't find any recent research on how many computers 
> exist on the 
> >Net, so I did my own:
> >
> >   http://www.firstpr.com.au/ip/host-density-per-prefix/
> >
> >I estimate about 107 million computers acknowledging pings.  Does 
> >anyone have insight into computers which are genuinely on 
> the Net but 
> >either do not acknowledge pings, or have those acknowledgements 
> >filtered out by a router?
> 
> Many many many ingress points now reject ICMP ping packets 
> because of the volume and potential for ping floods.

There are, I'm told, an estimated 600 million hosts, so I suspect that
many many many also do not do this; especially outside the west.

My favourite example was a large subnet of dsl modems in india which not
only pinged but had the default telnet admin access left open.

I expect that corporate networks and web hosts will often not ping, but
that ISP hosts almost always will; I've never seen an adsl modem that
defaults to no ping response.