[Andrew Martin:] Every time you sit down at a computer,
you have to trust that it's going to do what you expect,
whether it's that you type your email and you trust that
it's only going to go to the person you put as the addressee,
or whether it's that you're receiving your bank statement
and you trust that what you see on the screen is really what the bank knows
about your transactions and balance.
In order to do that, you have to rely on a vast number of components,
both in your own computer, and in the network and the servers at the other side of the network.
One thing that we know goes wrong is that computers catch viruses.
Computers have people breaking into them electronically
and changing the way they behave,
so this field of Trusted Computing has developed,
which is trying to think about how the design might be changed in such a way that that can't take place.
In the past, we've tended to keep most of our data and our documents,
all the things that matter to us,
on a hard disk on our own computer,
or perhaps on a server that's on our local network within the building where we're working,
or something of that sort.
That's turned out to be not as efficient,
as having a whole lot of computers somewhere else.
[Documentary Presenter:] "Thanks to today's super computers..."
[Andrew Martin:] We can share those servers if, when some people are asleep,
other people are working - all those things.
The Cloud can actually be a very green approach to computing.
But the downside is, if I've got particular data that I value for myself,
or if I'm processing somebody's private data
and I've got a strong legal obligation to process it carefully and fairly and safely,
it's much harder for me to know whether that's actually happening...
if it's on some server in The Cloud
and there may actually be a copy of it in Ireland and in San Francisco.
When I've got no further use for it,
I still have no guarantee that when I press delete,
it will actually get deleted.
It may persist forever because somebody else may find it useful,
or they may carelessly fail to delete it when I asked them to.
I need to protect my data, my processing, my resources
from the other users of the same Cloud resource.
I'm actually sharing that server with another company who might be my competitor.
I need to be fairly sure that my competitor doesn't get my data,
so I need the server to be good enough to make sure that doesn't happen.
The idea behind the T Clouds Project was to do this work of making sure that
the software running on a server in The Cloud is exactly the software that I wanted
and only releasing the data that might be quite personal or commercially sensitive,
when I've got a guarantee that it's running the right software.
[Sadie Creese:] It's a two-way authentication.
What you'll be familiar with at the moment is that,
if you do online banking,
you go in and you authenticate yourself to the bank,
the bank doesn't really do the same to you.
So we have a bunch of technologies designed here in Oxford
that solve that two-way piece.
[Andrew Martin:] Alongside that, you need lots of other pieces for the trust story,
you need to know who the service provider is,
what kind of policies they have around staff behaviour and server management,
who gets access to the room where all the servers are,
and all sorts of other things.
But all of those things sit in the background compared to
making sure that you've actually got the right software running.