Re: Relative performance of IPv6 and IPv4 for current users

["Craig A. Huegen" <chuegen@cisco.com>]

On Tue, 1 Jul 2003, Bill Owens wrote:

> There's a small debate going on within the Apple IPv6 mailing list
> over whether it is wise to have an application prefer v6
> connectivity, when it is available, over v4. The argument against

Anecdotal case:  about a year ago I was downloading BIND 9 from
ftp.isc.org.  I typed "ftp ftp.isc.org"; it wasn't obvious, but my machine
used the IPv6 address.  I couldn't understand why the transfer was only
getting roughly 1 KB/sec.  I used "ping" and "traceroute" and things
looked just fine.  It wasn't until I scrolled up and saw "entering
extended passive mode" that I finally realized the performance problem --
I was using IPv6.  A resulting traceroute6 showed my routing from my home
to Cisco to Japan back to ISC.

Being the enterprise network control freak that I am, I would really like
a standardized ability to prefer IPv4 over IPv6 until we feel comfortable
that IPv6 reachability and performance of the topology is up to par with
the IPv4 network.  I'm sure we'll do fine, but I imagine we'll have a
number of cases where we're asked to figure out performance problems and
will end up realizing it's because IPv6 was used over IPv4.

/cah

-- 
Craig A. Huegen, Chief Network Architect      C i s c o  S y s t e m s
IT Transport, Network Technology & Design           ||        ||
Cisco Systems, Inc., 400 East Tasman Drive          ||        ||
San Jose, CA  95134, (408) 526-8104                ||||      ||||
email: chuegen@cisco.com       CCIE #2100      ..:||||||:..:||||||:..