v6 & DSL / Cable modems [was: Private use of non-RFC1918 IP space (IPv6-MW)]

Mark Andrews Mark_Andrews at isc.org
Tue Feb 10 23:07:39 UTC 2009

In message <op.uo5nvrmrtfhldh at rbeam.xactional.com>, "Ricky Beam" writes:
> On Mon, 09 Feb 2009 21:11:50 -0500, TJ <trejrco at gmail.com> wrote:
> > Your routers fail frequently?  And does your traffic continue to get
> > forwarded?  Perhaps through another router?
> More frequently than the DHCP server, but neither are "frequent" events.   
> Cisco's software is not 100% perfect, and when you plug it into moderately  
> unstable things like phone lines (DSL) and cable networks, those little  
> bugs cause reloads -- you'd think they'd have better error handling, but  
> they don't. (I don't buy millions in equipment from Cisco so they don't  
> care about my problems.)  While I could use backup links, flip-floping  
> between ISPs with different addresses is not ideal (and that's as true for  
> v6 as v4.)
> > Why is there a problem with RAs being the first step, possibly including
> > prefix info or possibly just hinting @ DHCPv6?
> Because it doesn't fit the needs of *every* network.  In fact, it's only  
> "good enough" for very few networks.  As such it just adds more useless  
> layers of bloat.

	Good. You admit it fits the needs of some networks.
> > Well, as it stands now the RA isn't useless.
> ...
> > Also, it is not true in every case that hosts need a "lot more" than an
> > address.
> > In many cases all my machine needs is an address, default gateway and DNS
> > server (cheat off of v4 | RFC5006 | Stateless DHCPv6).
> It's useless.  It does NOT provide enough information alone for a host to  
> function.

	Hogwash.  The only thing needed for I used from DHCP on my
	laptop is router, address and netmask.  I actually discard
	anything else that is offered.  RA's meet my needs perfectly
	fine.  In fact they do a better job than DHCP for my needs.

	I don't trust dns servers returned by dhcp.  Lots of them
	don't offer the level of functionality I require.  I run
	my own recursive resolver to get the level of functionality
	I require.

> In your own words, you need a DNS server.  That is NOT provided  
> by RA thus requires yet another system to get that bit of configuration to  
> the host -- either entered manually, DHCPv6, or from IPv4 network  
> configuration (ie. DHCP!)  Forcing this BS on the world is a colossal  
> waste.  We've had a system to provide *ALL* the information a host needs  
> or wants in the IPv4 world for years.  Why it's not good enough for IPv6  
> is beyond me.
> --Ricky
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews at isc.org

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