Re: Reality Check and Ideas

August Zajonc (augustz nospam at bigfoot.com)
Tue, 09 Mar 1999 16:20:13 -0800

The caching aspect of DNS hit me just after I left my computer. Cache's are
starting to spring up for general http stuff, but most DNS implementations
come with a certain level of cache ready to go automatically (I can't think
of any that don't) because they make so much sense in the DNS world (and DNS
has TTL which works in contrast to most web pages which have no caching
directives).

In the http case, an earlier poster talked about possible ways to do the url
munging to allow caches to cache the data (avoiding '?' and so on)...

There is an interesting issue though. Will ISP's and campus IT department
want their DNS caches filling up with cddb info? What will it do to the hit
rate on the cache... Normally, those top 100 dns lookup occur A LOT
(www.yahoo.com, www.corporatehomepahge.com or msn.com or even the new
redhat.com :)... Will the same hold true with cddb data lookups (ie, will
there be a good hit rate on the cached data, or do people listen to too many
different things...) Of course, this isn't ACTUALLY that big a problem,
because the number of cddb data requests per day is likely to be minescule
when compared to the number of DNS lookups being performed... But it makes
for some interesting thoughts.

August

-----Original Message-----
From: Alan Cox <alan nospam at redhat.com>
To: cdindex nospam at freeamp.org <cdindex nospam at freeamp.org>
Date: Tuesday, March 09, 1999 4:03 PM
Subject: Re: Reality Check and Ideas

> To nitpick, DNS is easy. Two text files and a daemon. Technically, a web
> server is harder.
>
> The missing feature is mirroring/scaling/distributing. What if we just
took
> the exising CDDB protocol and made it work like news? That alone would be
a
> BIG win.

Umm news you post and it expires 4 weeks later or when you loose the disk.
News is a system for piping data to lots of places not replicating a
database.

DNS has scaling, it has mirroring (just declare 10 additional NS entries
and set them up as secondaries - its fault tolerant too then) and it has
distribution (you'll notice the secondaries do their own data copying)
and it has caching.

> An issue to point out is firewalls. Let's not wander into using new port
> numbers. Using the existing well-known port 80 seems as good an idea as
> any. Most sensible system administrators hide their machines behind
> firewalls. Let's make sure we can work with them for user queries.

Firewalls pass DNS and port 80. An http interface is a good policy anyway.
People sitting behind truely horrible proxies can then still use it.

Alan