Re: Warning of major NHS IT overspend

[Dave Howe <[EMAIL PROTECTED]>]

Peter Tomlinson wrote:
> DNS is a disciplined (OK, self-disciplined) method where data is used
>  all the time by messages coming from all over the world. Errors and
>  service outages are quickly obvious and we all as users expect them
> to happen from time to time and be quickly fixed by the professionals
> who operate the nodes in the internet.
*LOL* you must have a different internet to the one I work in. most DNS
records are horribly badly maintained - often *especially* those
block-maintained by large ISPs (because it just isn't a profit center) -
and the structure has no provision to in any way constrain someone
taking their record and placing it on a dialup connection from china, if
that is what they want to do.
If a major site (microsoft, say) has DNS issues, then it is all hands to
the pumps. if someone's hobby site has the same issues, then it can take
weeks or months for it to be fixed, not least of which is just locating
and making its owner aware he *does* have a problem - assuming it really 
is his problem, and not some DNS server or web proxy elsewhere in the 
path messing things up in its own unique way.

> Health centre databases are complex, managed by people of varying 
> degrees of competence and usually held in systems maintained by
> external suppliers. The outages and errors normally affect only the
> local service and cannot be tolerated by the remote A&E that in the
> distributed data architecture will be trying to access them.
the www is built on a disparate array of machines, managed by people of
varying degrees of competence and usually held in systems maintained by
external suppliers; DNS is simply an index into that system, just as
proxies "cache" frequently accessed pages to speed access to the data.
An effective distributed system could be modelled on DNS+Web quite
easily - DNS being the master index, itself maintained in a distributed
manner or centrally maintained by trained staff, and the individual
sites using commmon protocols to access and access-control the "content"
- the actual files.
you could for that matter use *actual* webservers for this - HTTPS is
relatively secure, can be (zip) compressed to enhance data rates, can
transmit anything, and can be supplimented by java applets and backend
databases to handle dynamic displays.  HTTPS also has some seldom used
but available authentication options involving the use of clientside
X509 certificates....





> No contest - but in the end its a political and (I hope) social
> decision which way to go.
>
> Peter