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IEEE article on overlay networks

Here's an article (PDF, 190KB) I wrote which will appear in the July/August issue of IEEE Internet Computing. (IEEE Copyright Notice: Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.)

As usual, comments welcome!

It's a short introduction to overlay networks and how they compare to "standard" flooding-type P2P networks (ie., Gnutella-type). Overlays are also discussed in the literature as distributed hash tables. (Because of the way they allow exact key/value pair mappings to be done over a network, and because they support basic hashtable operations: put/get/remove). It's written more for developers (or, if you will, for a general audience with technical proficiency) rather than researchers (not enough space to go in depth into the subject for that). It's quite something to write with limited space and for a subject like this one, that tends to be err... "mathematical". I end up feeling that not all the possibilities/ambiguities are explained, that sometimes in simplifying people will get the wrong idea, etc. This always happens, on any topic, on any magazine, or journal, or even when presenting for a conference (the typical 12 or 15 page limit sounds like a lot--it isn't). In the end the only way to scratch this particular "completeness" itch is to write a book.

It was an interesting experience, spanning several months: from initial draft, review, approval... a short period of quiet and then a flurry of activity in the last week or so, where we went from ugly zero-format Word document (using the Track Changes feature in word to collaborate with the editor) to nicely finished final layout-version, ready for inclusion in the magazine. The article's editor, Keri Schreiner was great to work with, and I learned a lot from the process. There are several "Editors" involved in the magazine of course, Lead Editor, Department Editor, and so on... when you think about it, it's fascinating, a process that might take say, six months in total (from idea to camera-ready copy), happening in parallel for a set of articles that will appear in a single magazine. It's a top down process mostly. It got me thinking about how it could be done in a less centralized way, which would improve feedback for all parties. I won't go into this in more detail now, though, I still have to post a follow up on the decentralized media discussion. :-)

Categories:, technology
Posted by diego on June 24, 2003 at 8:40 PM

So long, PocketPC, hello WM2003SPocketPC


So Microsoft released a new version of PocketPC and changed its name to (gulp!) "Windows Mobile 2003 Software for Pocket PC". Holy Cow. Sounds like someone wanted this one to be a Really Important Upgrade. Also, considering that only two revs ago PocketPC was Windows CE, we could get to the conclusion that their branding wasn't working. Mobile devices are proliferating in type, and this new rev of MS's handheld OS aims to combine both the PocketPC and Smartphone OSes under one brand, among other things. What's notable about this is the implied convergence that Microsoft sees as handhelds acquire phone functions, and viceversa. Note, however, that only the "Windows Mobile 2003 Software" part is what is generic to both PocketPC and Smartphone. I assume that the new Smartphone release due later this year (which will include support for the .Net compact framework, MS's clone of J2ME) will be "Windows Mobile 2003 Software for Smartphone". Nothing new as a concept, of course, but interesting since, for example Palm/Handspring seem more intent on adding phone features to palms than to support the whole range of form factors under a single "brand umbrella".

Regarding the Microsoft news, however, it's also interesting to note who are the partners with MS on this launch, and what products they are announcing. Basically PC Makers, and basically handhelds, except for Panasonic, who isn't really announcing anything.

A final note: Dell's announcement (in the article) is scary. Quote:

Dell doesn't plan to introduce a new model, but does plan to upgrade its existing Axim X5 product with the new operating system as well as offer a custom version of McAfee's VirusScan PDA (personal digital assistant) software
We've heard of a few occurrences of TXT viruses and things of the sort before, but until now I hadn't realized the havoc that could be created if you have, say, a hundred million MS-powered phones out there, loaded with personal information, maybe even e-payment information, and... full of security holes. Keep in mind that C#, which Microsoft says is as secure as Java, actually lets you access low-level routines if you want, thereby breaching the protection the VM would normally give you. This article does a good job of explaining the security model of Smartphone, and it can be summarized in two words: Code Signing. Which brings up two other words, the name of other widely deployed software whose security depends on Code Signing: Internet Explorer. Enough said. It's true that operator-controlled code signing has the potential to be more secure, since the operator could be monitoring in real-time the appearance of malicious software on the network and revoking execute privileges network-wide when that happens (as the article mentions). That assumes, however, that, a) the execution environment itself has no bugs (right...) and that b) the operators will invest in the infrastructure that this represents, both in terms of equipment and manpower. Don't hold your breath for that either. Conclusion: unless security is improved, as soon as a critical mass of Smartphones is deployed, we can expect the appearance of W32.Klez.Smartphone and similarly named e-vermin.

Categories: technology
Posted by diego on June 24, 2003 at 5:49 PM

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