Re: Internet Network issues

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

From: Phillip Windell (none)
Date: 02/06/04 

Date: Fri, 6 Feb 2004 09:27:57 -0600

The only thing ping actually tests is "ping" (ICMP). Ping does not
test TCP or UDP or GRE. Just because ICMP works doesn't mean the TCP &
UDP work.

It is possible to allow ICMP and not TCP/UDP, by the same token
TCP/UDP can be allowed while ICMP is blocked. So ping can test
physical connectivity but does nothing to test Layer4 and above.

You may have a firewall issue where it is flaking out on you, but I
don't know,...there just isn't anything given here to really go on. 

--
Phillip Windell [CCNA, MVP, MCP]
WAND-TV (ABC Affiliate)
www.wandtv.com
"David" <none@pacific.net.sg> wrote in message
news:OFel69I7DHA.2556@TK2MSFTNGP09.phx.gbl...
> Recently my company LAN has some internet traffic issues.
> For no apparent reasons, we will get disconnect from the internet.
> Internet Explorer will give the "Page cannot be display" message and
> downloads will be cut off etc.
> This problem happens intermittently (5-6 times) every day for 3
days.
>
> Whenever this problem happens, I did these:
> 1) ping to the website (both overseas and local)
> 2) tracert to the website
> 3) ping the DNSes (change to both our own DNS (Winnt4) as well as
ISP)
> 4) Check firewall (Gnatbox), SDSL unit (512kb leased line),
router(Chase
> IOlink)
>
> With these results:
> 1) website is responding, no drop pings. (pings using both IP
address and
> host name)
> 2) all the route hops are responding too
> 3) DNS are responding too, our local DNS do not have any error logs.
> 4) All other equipments are behaving normally, even restarted them.
>
> This is strange as ping packets are responding but internet traffic
is not.
> Anyone can shed some light?
>
> thanks
>
>
>

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