Guess again

Over in a fenland blog, there is a little discussion going on about passwords.  Evidently, Google has been doing some advertising about what makes a good password, and this has come in for some criticism.

In that blog post, Joseph Bonneau proposes an alternative one-liner:

A really strong password is one that nobody else has ever used.

(One of the commentors (J. Carlio) suggests modifications to add something about memorability. )

This is a seductive idea: it is, broadly, true.  It encapsulates the idea that you are trying to defeat brute force attacks, and that these generally succeed by attempting plausible passwords.

But I don’t think it’s good advice.    That is mainly because many people are poor with estimates that surround very large numbers: whether the likelihood of my password being used by someone else is one in a thousand, one in a million, one in a trillion (the word of the week, thanks to national debts) is something that, I would say, few people have a good intuition about.  In just the same way, people are poor at risk assessment for unlikely events.

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Aren’t spammers subtle?

Not having managed a blog with such a public profile before, I’m intrigued by the behaviour of those wanting to spam the comments field.

The blog is set up so that individuals from within the group can post using their Oxford credentials. Others can post comments, but the first time they comment, the comment must be moderated.

Some try posting their adverts for herbal remedies right away. Those are easy to spot and throw away.

There are several, though, who have posted comments like “I like this blog. You make good points.” I assume that the aim of these is that they are likely to get approved by a semi-vigilant moderator because then the commenter becomes a trusted poster.  Presumably, the advertising spam would follow thereafter.

I remark on this

  • (a) because other members of the group may moderate comments, and should be on the lookout for this ‘trojan’ behaviour;
  • (b) because it points to a greater degree of tenacity on the part of the spammers than I would have realised existed;
  • (c) because it seems a particularly hard problem to solve, CAPTCHAs notwithstanding.

webinos secure storage: a cross-platform dilemma.

Encrypted storage for sensitive data and credentials is an obvious requirement for any system with pretences towards being secure. As part of the webinos project, we have been thinking about solutions to this problem which work across multiple platforms.

As a brief recap: the webinos project aims to design and deliver an open source web runtime for four types of device: smartphones, media centres, PCs and in-car computers.  It will provide a set of standard JavaScript APIs for accessing device features from web applications, as well as synchronising data and providing a “seamless” end user experience.  We’re working on it with over 20 other companies and are primarily researching the security and privacy aspects of the system.  More details are available on our website: http://www.cs.ox.ac.uk/projects/webinos/

In webinos we think we have (at least) the following data to protect:

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