RE: traceroute-like tool for UDP or TCP packet

["K sPecial" <xzziroz () linuxmail org>]

----- Original Message -----
From: "Brian Austin" <baustin () ableinc com>
Date: Thu, 21 Aug 2003 15:23:26 -0700
To: <security-basics () securityfocus com> 
Subject: RE: traceroute-like tool for UDP or TCP packet

> > -----Original Message-----
> > From: Edward Rustin [mailto:ed () well com] 
> > On Thu, 21 Aug 2003, some guy wrote:
> >
> > > Linux uses UDP packets to traceroute, not ICMP packets like windows 
> > > does. Hope that helps, -Scott
> >
> > Not really.... an ICMP packet is a type of UDP packet. 
> > Basicly traceroute
> > works by sending a series of ICMP ECHO requests with 
> > increacing TTLs (time
> > to live - how many hops the packet can travel before it dies 
> > and aPacket
> > Timeout error is sent). A ping is also just a ICMP ECHO 
> > message, just with
> > a defualt TTL, rather than a series of increasing TTLs.
>
> Traceroute implementations vary across OS platforms.  ICMP is used for
> Windows but not *nix OS's, usually.  UDP is commonly used across
> Unix/Linux platforms.  More here:
> http://www.freesoft.org/CIE/Topics/54.htm
>
> > Make sure that the IS isn't blocking traffic coming back from 
> > a port 53,
> > or too a port 53 (make sure both UDP and TCP is open since a large DNS
> > relpy (over 1500 bytes I =think=) will get replied to oever TCP
> >
> > Edward Rustin
> > Directory of Security, OnlineGuardians.org
>
> All DNS client requests/replies are UDP, regardless of size (they're
> rarely, if ever, big).  DNS zone transfers, however, are TCP
> communications.
>
> BA
>
> ---------------------------------------------------------------------------
> ----------------------------------------------------------------------------

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