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MIT Researchers Create Platform To Build Secure Web Apps That Never Leak Data

swsuehr Re:April Fools Comes Early? (90 comments)

I realized you don't know what you're talking about right here. It would take until the heat death of the universe to brute force a 128-bit AES key.

Seems like you're making an assumption that AES itself hasn't been backdoored and that the implementation of the same is also correct, neither of which I would assume. Steve

about three weeks ago
top

MIT Researchers Create Platform To Build Secure Web Apps That Never Leak Data

swsuehr April Fools Comes Early? (90 comments)

It's a few days early for the April Fools edition of Slashdot. I'm sure the MIT researchers in question think they really have something here but it would be nice if they would've looked around before beginning their research. It seems as though this system connects to a server which then sends back encrypted data. That data is then decrypted at the local client. And they made a browser plugin for it. How is this fundamentally different than public key encryption?

The performance is horrible. From the Mylar web site, "a 17% throughput loss and a 50 msec latency increase for sending a message in a chat application." A 17% throughput loss and 50ms latency is *huge* for something as trivial as a chat application. Imagine what happens when real data is being crunched.

There are still enough attack vectors that make this a non-starter. First off, the encryption itself is still brute-forceable by a determined attacker with enough resources. Second, it assumes a secure client environment. Finally, it assumes that your adversary plays by the rules and won't inject malicious code or backdoors into the software or encryption, with or without a complicit service provider. The client code can check authenticity? Cute, but only works if your adversary doesn't "require" that the service provider comply with a secret order to say that the code is authentic, even when backdoored.

Steve

about three weeks ago
top

Onion Pi — Make a Raspberry Pi Into a Anonymizing Tor Proxy

swsuehr Re: Neat idea. (76 comments)

I'm doing exactly this. I have a Pi firewall running with three total ethernet ports (the third is a wifi DMZ). I got another Pi and it's running asterisk for the house with a POTS connection via an Obi110. However, based on the load and RAM usage I could be using a single Pi for both. Speed tests show that the Pi performs the same as the full scale computer that it replaced. Check my blog for more details on the firewall rig. I haven't blogged about the asterisk setup yet. Steve

about 10 months ago
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Ask Slashdot: the Best Linux Setup To Transition Windows Users?

swsuehr Why? (448 comments)

My first question is: Why? Why, if they're both hateful and fearful of change, would they need to change? Why not a newer version of Windows or a Mac?

Users aren't oriented towards their OS, they're oriented towards their tasks. Their typical question will begin with "How do I..." and then continue into "but then how do I...". So your first issue is to determine what they use and how they use it and then find out the best way to solve each of those individual use cases or problems. For example, "How do I manage my finances, I currently use Quicken?" or "How do I upload pictures from my camera?". You need to solve each of those use cases in a sane manner that's easy to use and just as good or better than what they have. Typical users, especially the ones you describe, don't want to spend any more time with their computer than they need to.

Don't underestimate a user's ability to forget things that they do on their computer. Again, they're task-oriented and so they won't necessarily remember that they need a certain program to update some infrequently used spreadsheet twice a year.

Only if you can help them complete their tasks should you switch; you shouldn't switch them to Linux because you perceive it as better; it might not be better for them and then they'll have a tainted view of Linux when in fact the problem was that they couldn't use their silly banner-creation software from 1999 on it.

about a year and a half ago
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Ask Slashdot: Tips For Designing a Modern Web Application?

swsuehr HTML5/JS Plus Backend (409 comments)

Hi,

Well, you're going to need a presentation layer, which may or may not be obvious to you but HTML5 and JavaScript. You'll want to learn JavaScript but shortcut the process with jQuery and jQuery UI. And of course CSS3. So now you've got a pretty frontend, look and feel, behaviors, etc.

For the backend why not stick with Java? You know it already. If you're thinking PHP then that's fine too but stay away from the frameworks and shortcuts for PHP because they always end up becoming a burden down the road for upgrades, ongoing maintenance, and expansion.

I've had great luck with LAMP stack and with today's cloud bits and strong hosting providers, getting the infrastructure is easier than ever.

And if you're looking for books, try my JavaScript Step by Step book for JavaScript related (it includes jQuery too). O'Reilly has some good HTML5 material too.

Steve

about 2 years ago
top

Google Introduces Programming Challenge In Advance Of GoogleIO

swsuehr Only Developers Could Write This (114 comments)

Ugh. Seeing a sentence like this "...architect a machine only you could have dreamt of" makes me think that they may want to consider allowing just *one* non-developer... someone who can write.

Steve

more than 2 years ago
top

Brain Implants Can Detect What Patients Hear

swsuehr Tech Support (75 comments)

Earlier in my career when I had to do level 1 tech support I might have liked opportunity to cut holes in skulls to make sure people heard what was being said. However, *hearing* what's being said and actually processing that into meaningful and actionable instructions are two different things.

more than 2 years ago
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Ask Slashdot: Making JavaScript Tolerable For a Dyed-in-the-Wool C/C++/Java Guy?

swsuehr use strict (575 comments)

The latest ECMAScript standard includes the 'use strict' pragma, which is one step towards what you're looking for.

Also, I was playing with Visual Studio 11 Express preview and it includes some decent code completion for JavaScript, which maybe fulfills some of your IDE stuff; though admittedly I haven't put it through its paces to see how well it does JavaScript code completion. Eclipse for JavaScript developers might do the same, I honestly haven't used it in a while for JavaScript writing. (I still prefer Vi for coding, versus an IDE, fyi).

Use the tools in Chrome or Firebug for Firefox to help with debugging.

You won't find the same advantages of compile-time error checking that you currently have but it also forces you to become more disciplined about thinking through your code and test cases when writing JavaScript. Obviously, the tradeoff is that if you don't test for it you won't find the error until someone finds it in the live environment.

Others have pointed out jQuery and I'll echo that. However, if you're like me you'll want to learn some of the underlying bits or the "why" something works and then augmenting with jQuery and other libraries. You'll want jQuery for most of the frontend work that you do.

And finally, I can't talk JavaScript without shamelessly plugging my book, JavaScript Step by Step.

Steve

more than 2 years ago
top

Google Launches Google+ Social Network

swsuehr I'm Going For It (368 comments)

Since I seem to be the last person on earth without a Facebook account, I think I'll sign up for this and start sending invites to all of those people on Facebook who keep spamming me to join.

Anyone have any invites to spare?

Steve

more than 2 years ago
top

Thinking of Publishing Your Own $0.99 Kindle Book?

swsuehr Maybe Raise the Price? (101 comments)

As someone who has written several books (ok, shameless self-promoting link to the latest one) I might suggest that you raise the price. Sound counterintuitive? People may be looking at your book and the price point of $0.99 and thinking "this might be a scam or reprint of some material already on the web." By raising the price to say $9.99 or $14.99 you're still below the traditionally published books but also give the appearance of extra value; the consumer is getting something valuable.

I know nothing of the self-publishing world, though I have considered it at various times. But if I was going to be publishing something for Kindle I'd likely be setting it at a higher price point to give my book separation from the spam.

Oh, typically royalties are in the 8% to 15% range for tech books, depending on the publisher and the deal being offered. The royalties are sometimes higher on the eBook versions. However, realize that the royalties are off of the wholesale price not the list or sale price. So if retail on JavaScript Step by Step is $39.99, Amazon has it for $25, but the publisher sold it to them for $20, I get a percentage of the $20 not of the $39.99.

YMMV.

Steve

more than 2 years ago
top

No Additional Firefox 4 Security Updates

swsuehr Re:Who is This Helping? (445 comments)

It helps Mozilla by reducing the amount of code they have to maintain at one time. With a six-week release schedule, if they had to maintain each version for a year, they'd end up supporting eight or nine version simultaneously.

But it's simply not realistic for the software to change significantly in 6 weeks. Web standards don't change that much in 6 weeks to warrant this much changing in the browser. Therefore, they're supporting largely the same codebase for months and months, same as before. At some point they add major new features and these are the ones that should get the new major version number.

Simply incrementing the major version every 6 weeks will hurt Mozilla and Firefox.

more than 2 years ago
top

No Additional Firefox 4 Security Updates

swsuehr Re:Who is This Helping? (445 comments)

Can you cite any examples where something worked in Firefox 4 but not Firefox 5?

Asking what is broken within *this* particular version is completely missing the point. The point is that someone needs to now go back to their PHB and say that FF is now at new version. Resources for the business need to be taken to examine what changed and how those changed bits will affect the organization's web site. And now this process needs to be repeated every six weeks.

At some point, something major *will* change between versions. In the past, one could look at it and say "ok, version 4.0.1 came out, probably just addressed something minor. Version 5 just came out, must be a major new release, we should look at what changed." The new numbering scheme and release schedule makes it much more time consuming to support Firefox because now every release needs to be examined with the care and attention previously only reserved for major versions.

Well-publicized schedule? New version every 6 weeks.

You missed the word "sane" in my post. Six weeks != sane release schedule for major versions of this software. And yes, the version number incrementing *does* indicate a major version.

You're right again in that people don't want to update their software, that's why Firefox (again like Chrome) does it automatically.

Hmm. Not sure if FF actually does update automatically between major versions, I didn't think so. In any event, major version changes in Firefox have broken add-ons which is a failure for the user.

I don't care if Mozilla releases every 6 weeks, every 3 weeks, or every 3 hours. I do care about supporting the browser on multiple web sites and having to work with developers and users alike. Keeping the version numbers on a major/minor/bug fix scheme actually does work; it wasn't a broken model. This version number bouncing is not for the benefit of the user. Seems to be Mozilla with a case of version number envy; their number is smaller than IE and Chrome and they want to fix it, regardless of whether it benefits anyone.

more than 2 years ago
top

No Additional Firefox 4 Security Updates

swsuehr Who is This Helping? (445 comments)

Who, exactly, is the rapid release schedule helping? It's certainly not helping web developers and organizations who try to list their supported browser versions and actually try to code towards those versions. The quickest path to get the corporate PHBs to stop supporting your browser is to have the IT staff say "Guess what, the next version of Firefox is already out so we need to make updates." At some places, support for browsers other than IE is tenuous at best, so making it more difficult to support these browsers only hurts the browser manufacturers.

Want to gain more support? Release a stable product, with wide support for standards and add-ons, and do so on a sane, well-publicized schedule. People don't care about version numbers; updating software isn't something people want or like to do. Why are you making it more difficult and cumbersome for users to use your product?

more than 2 years ago
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No More Version Numbers For HTML

swsuehr Er, Why use Version Numbers At All? (336 comments)

I broke the cardinal rule and read TFA. From TFA:

"Hickson mentions that the group will be dropping the HTML5 name immediately, but it we have not received a confirmation that this will happen over at the W3C as well."

So WHATWG will no longer be using numbers? WHATWG can call it "Hullapuhjelpus" as far as I'm concerned as long as W3C still continues using version numbers. Version numbers provide excellent reference points to featuresets and are useful to implementers, developers, and end users alike.
From the WHATWG Blog:

"However, shortly after that we realised that the demand for new features in HTML remained high, and so we would have to continue maintaining HTML and adding features to it before we could call "HTML5" complete, and as a result we moved to a new development model, where the technology is not versioned and instead we just have a living document that defines the technology as it evolves."

Because there's demand for new features you no longer want to use a numbering scheme? Many standards are evolving. Why not just increment the minor version when new features are added? HTML version 5.1 added this cool thing, 5.2 this cool thing, etc.

If we're dumping version numbers then why bother calling it Internet Explorer 6, 7, 8, and 9? Why not just call it "Internet Explorer"? We all know that each of those versions render pages the same, right? Hmm. I just realized that I invoked Internet Explorer in a discussion about standards. Mea Culpa.

How does removing the version number help the people who need to implement and work with the standard?

more than 2 years ago
top

Five Billionth Device About To Plug Into Internet

swsuehr I'm counting (162 comments)

It's my job to count these. There are over 16,000,000 hosts that respond to ping on my network alone. If everyone does this I can see how the number would grow exponentially.

nmap -sP 127.0.0.0/8

more than 3 years ago
top

Murdoch-Microsoft Deal In the Works

swsuehr They *still* don't get it? (468 comments)

Microsoft seems to have a long history of not understanding the Internet. Witness them being very late to the party with Internet Explorer, and then not being smart enough to figure out that they should set a default home page to their sites with early versions of IE. And then the various attempts at lock-in and biased search results over the years.

I can't help but think this is yet another example of Microsoft attempting to make the Internet into something that they want it to be, something that benefits only them, rather than something that benefits society as a whole. People won't change their habits so easily, they'll just use whatever sites come up in Google. This will be a boon to those sites that remain in the Google index.

more than 4 years ago
top

Why Corporates Hate Perl

swsuehr Corporate Types (963 comments)

I learned long ago not to listen to corporate types if I wanted insight into something technical. It's not Perl that's the problem, it's the corporate types who make decisions with incomplete information and without the qualifications, experience, and knowledge to make informed decisions. They're in over their heads and look for any way to make a decision that makes them look smarter and gives them more influence, while hiding the fact that they haven't a clue.

I've seen many cases where one influential corporate type who is viewed by other, higher, corporate types as having a clue, will be the one who plants the bug that $language is legacy, inefficient, or otherwise bad. Usually that's not because that person knows his or her stuff, but rather because said person doesn't know anything about $language and wants to promote something he or she knows.

I've been involved in projects to replace perfectly maintainable code on well-maintained servers that's been running for many, many years with code that runs on somewhat more closed systems and will inevitably need to be upgraded in a never-ending cycle whenever the system vendor changes their paradigm and architecture. All because one corporate type had undue influence and the people higher in the chain, who won't be around for the next 10 years, want to show they're doing something and justifying their multi-million dollar IT budgets.

As others have pointed out, I too have seen plenty of unmaintainable code in every language. It's not the language that's at fault, and I might even argue that sometimes it's not even the individual programmer's fault but rather the fault of someone or some process that called for the program to be written in 3 hours just so that a project manager could hit their deliverable date. In the corporate world, my experience is that bad code comes more from bad processes than it does from bad programmers.

more than 4 years ago

Submissions

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Book Review: The Book of Xen

swsuehr swsuehr writes  |  more than 4 years ago

swsuehr (612400) writes "The Book of Xen (Takemura and Crawford, No Starch Press, 2009) provides an excellent resource for learning about Xen virtualization. I frequently need to create test environments for examples that appear in various books and magazine articles (in the interest of full disclosure, I've never written for the publisher of this book). In the days before virtualization that meant finding and piecing together hardware. Like many readers, I've been using virtualization in one form or another for several years, including Xen. This book would've saved hours searching around the web looking for tidbits of information and sifting through what works and doesn't work in setting up Xen environments. The authors have done the sifting for me within the ~250 pages of the book. But far beyond, the authors also convey their experience with Xen using walkthroughs, tips, and recommendations for Xen in the real world.

"The Book of Xen", "A Practical Guide for the System Administrator"

As stated in the subtitle, The Book of Xen is written with the system administrator in mind; someone who is comfortable with tasks like installing Linux and working with the command line. While it wouldn't be impossible for someone completely new to Linux to accomplish the tasks in the book, a bit of experience would go a long way to both visualize and complete the installation and configuration steps shown in the book. As stated in the introduction, the book is organized "(mostly) alternating between theoretical and practical discussion [because] an admin needs both practical experience and a firm theoretical ground to effectively solve problems..." (xxiii).

The authors do an excellent job of explaining what Xen is and where it fits in the virtualization landscape. This explanation begins with the introduction where the reader gathers a brief history of virtualization along with Xen's place in the landscape. Xen's limitations and reasons for using Xen are also covered right in the introduction, along with an overview of the book.

Chapter 1 begins with a high-level overview of Xen. This discussion is excellent if only to get the readers on equal footing for the discussions to come later in the book. Included in this chapter is a discussion of various techniques for virtualization including Full Virtualization, OS Virtualization, and Paravirtualization. The section on Paravirtualization leads nicely into some of the underlying details of scheduling, interrupts, and memory, and other resource management which are handled by Xen and discussed later in the chapter.

Chapter 2 sends the reader down the path of installing and using Xen. It's a short chapter, coming in at about 9 pages, and the reader is expected to be able to handle an install of CentOS with just a bit of guidance from the authors on specific options to select. This is a key point for those among us who have a preference for a certain Linux distribution. The book isn't tied specifically to a single distro, as the authors note in the introduction, "[w]e've tried to keep this book as distribution- and version-independent as possible, except in the tutorial sections, where we try to be extremely specific and detailed..." (xxiv). The base or host system upon which the examples run is based on CentOS, which the authors acknowledge and highlight in Chapter 2, "[f]or the purposes of this chapter, we'll assume you're installing CentOS 5.x with the server defaults and using its built-in Xen support. If you're using something else, this chapter will probably still be useful, but you might have to improvise a bit" (13). There is discussion of the Xen-tools package in a later chapter which shows its installation under Debian Linux too. So far from being tied to one distro, the book is refreshingly neutral in this regard.

By the end of Chapter 2, the reader has a working Xen host system and a domain 0 or dom0 host upon which to provision virtual machines. Included in Chapter 3 is a discussion of how to provision guest operating systems, known as domU in Xen-speak. The authors devote a good number of pages to making this task clear, and work through examples of basic domU installation and the use of package management systems and Debian's debootstrap to create domUs. Additionally in Chapter 3 the reader learns how to convert VMware disk images to a format usable by Xen.

Chapters 4 and 5 examine details of the Xen backend, including storage and networking. Chapter 4 stands out for its recommendation of blktap and LVM (Logical Volume Manager) as the storage backend as well as an overview of LVM itself, along with the use of networked storage for Xen.

Chapter 6 looks at tools for management of Xen, focusing on Xen-tools, libvirt, and Xen-shell while Chapter 7 gives advice for hosting untrusted users with Xen. Chapter 8 discusses the use of Xen with Unix-like operating systems and includes sections on Solaris and NetBSD.

The ability to migrate the virtual machine from one physical machine to another is one of the advantages of virtualization. As pointed out by the authors, a virtual machine might be migrated to take advantage of newer hardware, to perform maintenance, or any number of other reasons. Chapter 9 is of interest for its discussion of Xen migration. Cold and Live migrations are examined and Footnote 1 on page 126 is interesting for its reference to the Kemari Project and Project Remus which are projects to add hardware redundancy to Xen.

Tools and techniques for the measurement of Xen performance are shown in Chapter 10, which walks the reader through basic usage of well-known tools such as Bonnie++, httperf, UnixBench, and others. More importantly for the Xen admin is the discussion of Xen-aware profilers like Xenoprof which is "a version of OProfile that has been extended to work as a system-wide profiling tool under Xen..." (151).

Chapter 11 covers the Citrix XenServer, which is the enterprise-grade commercial Xen product from Citrix. The authors summarized it best in the review of Chapter 11: "Can Citrix's product replace the open source Xen? As always, the answer is maybe. It offers significant improvements in management and some interesting new capabilities, but that's balanced against the substantial cost and annoying limitations" (174).

Chapter 12 begins the discussion of Hardware Virtual Machines (HVMs), which are virtualization extensions that enable "an unmodified operating system [to run] as a domU" (176). This means the ability to run an unmodified version of Microsoft Windows as a guest OS within a Xen environment. The HVM discussion in Chapter 12 leads nicely into Chapter 13, "Xen and Windows".

The main chapters of the book end with Chapter 14, "Tips", and Chapter 15, "Troubleshooting". Both chapters draw on the experience of the authors and provide value to the book for their recommendations. Though the tool of choice for troubleshooting is the nearest Google search box, it's still helpful to glance over the content in the Troubleshooting chapter if for no other reason than to maybe remember that it's there when you receive the dreaded "Error: DestroyDevice() takes exactly 3 arguments" error.

The Book of Xen is almost certainly a time-saver for anyone looking to implement Xen or virtualization with Linux. The back cover states "The Complete Guide to Virtualization with Xen". The book lives up to that statement and more."
top

The Book of Xen

swsuehr swsuehr writes  |  more than 4 years ago

swsuehr (612400) writes "The Book of Xen (Takemura and Crawford, No Starch Press, 2009) provides an excellent resource for learning about Xen virtualization. I frequently need to create test environments for examples that appear in various books and magazine articles (in the interest of full disclosure, I've never written for the publisher of this book). In the days before virtualization that meant finding and piecing together hardware. Like many readers, I've been using virtualization in one form or another for several years, including Xen. This book would've saved hours searching around the web looking for tidbits of information and sifting through what works and doesn't work in setting up Xen environments. The authors have done the sifting for me within the ~250 pages of the book.

"The Book of Xen", "A Practical Guide for the System Administrator"

As stated in the subtitle, The Book of Xen is written with the system administrator in mind; someone who is comfortable with tasks like installing Linux and working with the command line. While it wouldn't be impossible for someone completely new to Linux to accomplish the tasks in the book, a bit of experience would go a long way to both visualize and complete the installation and configuration steps shown in the book. As stated in the introduction, the book is organized "(mostly) alternating between theoretical and practical discussion [because] an admin needs both practical experience and a firm theoretical ground to effectively solve problems..." (xxiii).

The authors do an excellent job of explaining what Xen is and where it fits in the virtualization landscape. This explanation begins with the introduction where the reader gathers a brief history of virtualization along with Xen's place in the landscape. Xen's limitations and reasons for using Xen are also covered right in the introduction, along with an overview of the book.

Chapter 1 begins with a high-level overview of Xen. This discussion is excellent if only to get the readers on equal footing for the discussions to come later in the book. Included in this chapter is a discussion of various techniques for virtualization including Full Virtualization, OS Virtualization, and Paravirtualization. The section on Paravirtualization leads nicely into some of the underlying details of scheduling, interrupts, and memory, and other resource management which are handled by Xen and discussed later in the chapter.

Chapter 2 sends the reader down the path of installing and using Xen. It's a short chapter, coming in at about 9 pages, and the reader is expected to be able to handle an install of CentOS with just a bit of guidance from the authors on specific options to select. This is a key point for those among us who have a preference for a certain Linux distribution. The book isn't tied specifically to a single distro, as the authors note in the introduction, "[w]e've tried to keep this book as distribution- and version-independent as possible, except in the tutorial sections, where we try to be extremely specific and detailed..." (xxiv). The base or host system upon which the examples run is based on CentOS, which the authors acknowledge and highlight in Chapter 2, "[f]or the purposes of this chapter, we'll assume you're installing CentOS 5.x with the server defaults and using its built-in Xen support. If you're using something else, this chapter will probably still be useful, but you might have to improvise a bit" (13). There is discussion of the Xen-tools package in a later chapter which shows its installation under Debian Linux too. So far from being tied to one distro, the book is refreshingly neutral in this regard.

By the end of Chapter 2, the reader has a working Xen host system and a domain 0 or dom0 host upon which to provision virtual machines. Included in Chapter 3 is a discussion of how to provision guest operating systems, known as domU in Xen-speak. The authors devote a good number of pages to making this task clear, and work through examples of basic domU installation and the use of package management systems and Debian's debootstrap to create domUs. Additionally in Chapter 3 the reader learns how to convert VMware disk images to a format usable by Xen.

Chapters 4 and 5 examine details of the Xen backend, including storage and networking. Chapter 4 stands out for its recommendation of blktap and LVM (Logical Volume Manager) as the storage backend as well as an overview of LVM itself, along with the use of networked storage for Xen.

Chapter 6 looks at tools for management of Xen, focusing on Xen-tools, libvirt, and Xen-shell while Chapter 7 gives advice for hosting untrusted users with Xen. Chapter 8 discusses the use of Xen with Unix-like operating systems and includes sections on Solaris and NetBSD.

The ability to migrate the virtual machine from one physical machine to another is one of the advantages of virtualization. As pointed out by the authors, a virtual machine might be migrated to take advantage of newer hardware, to perform maintenance, or any number of other reasons. Chapter 9 is of interest for its discussion of Xen migration. Cold and Live migrations are examined and Footnote 1 on page 126 is interesting for its reference to the Kemari Project and Project Remus which are projects to add hardware redundancy to Xen.

Tools and techniques for the measurement of Xen performance are shown in Chapter 10, which walks the reader through basic usage of well-known tools such as Bonnie++, httperf, UnixBench, and others. More importantly for the Xen admin is the discussion of Xen-aware profilers like Xenoprof which is "a version of OProfile that has been extended to work as a system-wide profiling tool under Xen..." (151).

Chapter 11 covers the Citrix XenServer, which is the enterprise-grade commercial Xen product from Citrix. The authors summarized it best in the review of Chapter 11: "Can Citrix's product replace the open source Xen? As always, the answer is maybe. It offers significant improvements in management and some interesting new capabilities, but that's balanced against the substantial cost and annoying limitations" (174).

Chapter 12 begins the discussion of Hardware Virtual Machines (HVMs), which are virtualization extensions that enable "an unmodified operating system [to run] as a domU" (176). This means the ability to run an unmodified version of Microsoft Windows as a guest OS within a Xen environment. The HVM discussion in Chapter 12 leads nicely into Chapter 13, "Xen and Windows".

The main chapters of the book end with Chapter 14, "Tips", and Chapter 15, "Troubleshooting". Both chapters draw on the experience of the authors and provide value to the book for their recommendations. Though the tool of choice for troubleshooting is the nearest Google search box, it's still helpful to glance over the content in the Troubleshooting chapter if for no other reason than to maybe remember that it's there when you receive the dreaded "Error: DestroyDevice() takes exactly 3 arguments" error.

The Book of Xen is almost certainly a time-saver for anyone looking to implement Xen or virtualization with Linux. The back cover states "The Complete Guide to Virtualization with Xen". The book lives up to that statement and more."

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