Marimba Inc president and chief executive Kim Polese wants us to think of her company as separate from the morass of push technology companies – Marimba’s Castanet push is not about shoveling content, which is the job of other dumb push technology companies, such as PointCast Inc. Speaking at the start of Networld+Interop here in Las Vegas yesterday, Polese went on the offensive against PointCast, BackWeb, Intermind and others. She said the dumb push is distracting, a bandwidth and diskspace hog – there’s no need to downoad a whole file if all you want to do is update one word, she says. It’s difficult to get rid of once you’ve got it, it’s not easy to personalise, and it’s definitely not secure. Castanet uses the Java sandbox model, a secure area on the hard disk that only applications downloaded by Castanet can access. Polese says encryption and authentication are not sufficient protection against bombs and viruses. Castanet’s only security right now is the sandbox, as it only distributes Java applications, but Marimba is the process of adding encyption, authentication and billing capabilities that will enable it to distribute non-Java applications, such as Dynamic Link Libraries (DLLs), and RealAudio and ShockWave plug- ins, for example (CI No 3,134). With authentication and encryption, users will know where the applications came from, and whether they can be trusted to access their computer’s file system safely, so the theory goes. Marimba is using the MD5 message digest algorithm designed for compressing large messages and then assigning private keys to them – Polese called it fingerprinting the files. In the kind of software distribution Marimba has in mind, comprising hundreds or even thousands of minor updates each month, many versions of the same file need to be downloaded, without the need to change the file name each time; hence the fingerprinting. Marimba has a licensing deal with Security Dynamics Technologies Inc’s RSA Data Security Inc subsidiary to use its encryption technology. Meantime, following all the recent talk of the advantages of multicasting versus conventional push and the plethora of companies licensing Tibco Inc’s TIB multicast technology (CI No 3,154), Polese said Marimba was integrating multicasting into Castanet – it’s ideal for updating real-time financial information, for instance – and she confirmed that the company is talking with a number of multicast companies, Tibco Inc among them. Although Polese has been subjected to ridiculous amounts of hype by the media, perhaps the message about Castanet has been lost in all the verbiage – no doubt that’s the reason for an hour-long Castanet advertisement drassed up as a keynote speech she gave yesterday.