Subject: Where Can I get "pathchar" source code ?

From: [email-masked]
Date: Wed, 12 Jul 2000 12:50:12 +0900

From: 김현수 4264@DACOM on 2000-07-12 12:50 PM

To:   [email-masked]
cc:
Subject:  Where Can I get "pathchar" source code ?

Hi,
  I am a researcher of DACOM(Korean Telecommunications Company) R&D Center.

  Among Internet characterization parameters, I am interersted in bandwidth of a
link/path.
  Could anyone introduce some sites providing "pathchar" source code ?
  This helps me characterize IP network of my company.

  By the way, I have a question ...
  What's the difference between a bottleneck b/w and an available b/w?
  Which of b/w's can "pathchar" give me?

  Thank you.
  - Soo

---

From: [email-masked] (Bruce A. Mah)
Date: Tue, 11 Jul 2000 22:33:14 -0700

>   This helps me characterize IP network of my company.

Hi Soo--

Unfortunately the source code to pathchar has not yet been released to
the public at large.  However, there are at least two open-source
alternatives, based on the algorithms used in pathchar, as described by
a talk that Van Jacobson gave at MSRI in 1997.

pchar is a version that I did while at Sandia National Laboratories.  It
runs on a variety of UNIX systems, and runs several different analysis
algorithms over both IPv4 and IPv6.  pchar is available from:

http://www.employees.org/~bmah/Software/pchar/

clink ("characterize links") is another implementation by Allen B. 
Downey of Colby College.  His version runs on Linux, and it has some 
options for more accurate timestamping of packets within the Linux 
kernel.  clink is available from:

http://www.cs.colby.edu/~downey/clink/

Both the pchar and clink Web pages have some links to other related 
information about pathchar.

(Why are there two versions?  We started independently and neither of us
quite realized what the other was doing until we were mostly done.)

>   Which of b/w's can "pathchar" give me?

The available bandwidth along a path between two Internet hosts is 
equal to the bandwidth at the bottleneck.  In other words, in the 
context of pathchar, they're the same thing.  

Hope this helps...

Bruce.