[e2e] method to detect liveness of remote other than ping
Cottrell, Les
cottrell at SLAC.Stanford.EDU
Mon Oct 13 07:46:52 PDT 2003
The PingER project (http://www-iepm.slac.stanford.edu/pinger/) is somewhat similar to what you are describing. PingER is used to measured the Internet performance from about 35 sites in 12 countries to about 500 sites in about 80 countries and uses ping. PingER frequently runs into the problem with blocked pings, especially in the developing world (though by no means only, for example most Australian academic hosts appear to have pings blocked in a router in Washington State. We have found that the best way round it is to have an interested party (not necessarily a networker) at the remote site who one works with to get the pings allowed from some particular host or subnet to a particular host at the remote host. This is very time consuming, since one has to first detect the problem and identify it as ping blocking/rate limiting, and then contact the interested party, explain what one is doing and why, also why is it of benefit to the remote site, and what are the possible
solutions. If it is the remote site doing the blocking one will then typically be put in contact with their network people and have to work with them. This is usually successful can can take months of emails. If it is a service provider doing the blocking this is even harder (we have been working, without success, for 4 months to get access to a host in Vietnam to which pings are blocked by the service provider who does not answer emails).
-----Original Message-----
From: Jing Shen [mailto:jshen_cad at yahoo.com.cn]
Sent: Monday, October 13, 2003 3:21 AM
To: Anilkumar Vengalil (MOBIS/dor)
Cc: end-to-end list
Subject: Re: [e2e] method to detect liveness of remote other than ping
Hi,
thanks a lot.
Our situation is that: we need to set up network
availablity montoring across the backbone network. But
some sites filtered out both traceroute and ping at
their edge router. We could see in/out traffic in
access switch, but sampling by SNMP every 5min is too
long to realize a real-time monitoring.
regards
jing shen
--- "Anilkumar Vengalil (MOBIS/dor)" <vengalil at fokus.fraunhofer.de> 的正文:>
> Hi,
>
> In addition to ping, one can also use the ICMP based "traceroute" to
> detect the liveness of remote machine. Traceroute
> will report the complete
> route ( the routers through which the traceroute
> packets flow from your
> machine to the remote machine )
>
> There are other ways like sending a TCP segment and
> look for the reply
> (like RST or SYN/ACK) from the remote machine. But I
> am not aware of any
> tools which do so. Further, such attempts could be
> observed as attacks.
>
> -Regards,
>
> Anil
>
> On Mon, 13 Oct 2003, [gb2312] Jing Shen wrote:
>
> > Hi,
> >
> > Usually, we detect remote end liveness by 'ping'
> > remote end IP address. I want to know, if ping
> packet
> > is filtered out by firewall which tools could be
> used
> > to detect remote end liveness?
> >
> > thanks
> >
> > jing shen
> >
> >
> >
> >
> >
>
' spam control '
=====
Jing Shen
State Key Lab of CAD&CG
ZheJiang University(YuQuan)
HangZhou, ZheJiang Province 310027
P.R.China
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