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User: rsilverman

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  1. Re:You do the crime, you do the time. on Alan Turing Gets an Apology From Prime Minister Brown · · Score: 5, Insightful

    You're missing the point. Brown is not apologizing for Britain having behaved *illegally*, or for having prosecuted Turing. The law was applied as written at the time (I'm assuming; I haven't checked). He's apologizing for Britain's treatment of Turing, period. The law was unjust, and the results horrific. Britain is recognizing this and doing the only thing it can at this point: express its regret.

  2. Re:There's something very wrong here. on Making Sense of Mismatched Certificates? · · Score: 1

    The problem is that CapitalOne's web server does not supply the certificate for the intermediate CA which issued the server's cert, so Firefox can't make a chain back to the root (which it does have). The reason it works in some other browsers, is that the web server cert itself contains a pointer to the needed certificate embedded in it; the browsers in which it works fetch the intermediate cert from there; Firefox simply doesn't do that. It actually works in the latest release of Firefox, as well.

  3. classic papers on Programming Erlang · · Score: 2, Informative

    Here is a classic paper on the style and advantages of functional programming:

    http://www.math.chalmers.se/~rjmh/Papers/whyfp.htm l

    Also, John Backus' Turing Aware lecture, "Can Programming Be Liberated from the Von Neumann Style?"

    http://www.stanford.edu/class/cs242/readings/backu s.pdf

  4. Re:a few facts on SSH Claims Draw Open Source Ire · · Score: 1

    If you allow shell access, then of course such restrictions are ineffective, since people can install/use their own forwarders, as you did. To make them effective, you restrict the relevant accounts to port forwarding only.

  5. a few facts on SSH Claims Draw Open Source Ire · · Score: 5, Informative

    There's a lot of exaggeration and vagueness on both sides of this little
    tempest. What suffices for one enterprise may not for another, so it is
    certainly silly for ssh.com to claim that OpenSSH is not
    "enterprise-class" -- as Theo and others rightly point out, OpenSSH is
    used successfully in many large contexts. On the other hand, it is a fact
    that Tectia has a number of features OpenSSH lacks, some of which are
    particularly relevant to large organizations (which is not the same as
    simple widespread use). Here are a few of them:

    * PKI support

    Tectia can use X.509 certificates for both client and server
    authentication. To add a new SSH server or change an existing one's host
    key, all you need do is issue a certificate for it. Clients need only
    have a copy of a single public key: the issuing CA certificate. No
    constantly shifting mess of per-user and per-host known-host files to try
    to keep in sync, no spurious "unknown host" or "host key changed messages"
    confusing users and teaching them to ignore security warnings. It just
    works.

    For client authentication, there are no burgeoning copies of
    authorized_keys files lying around, unmanaged, needing to be individually
    tracked down whenever you want to turn off someone's access: instead, you
    can simply revoke the user's certificate. And flexible rules can grant
    access based on certificate attributes, like "anyone in the Foo Department
    can log into this host."

    The distributed-trust problem has been addressed abstractly by systems
    like PKI and Kerberos. In a large (or even medium) scale environment, you
    want to tie applications such as SSH into these systems, not have each one
    use its own ad-hoc mechanism.

    Note that both OpenSSH and Tectia support Kerberos. There is some
    variation in how well they use it to address the above problems, though,
    and I won't get into that here.

    * Greater configuration flexibility

    With the Tectia SSH server you can:

    + Modify almost all server parameters based on the client hostname and
    address, or properties of the requested account (username and group
    membership). Thus you can arrange that, accounts in one group permit
    password authentication, while those in another group require
    public-key -- or that connections coming from your internal network
    allow a wide range of ciphers, while those coming from the outside
    require a smaller, stronger set. You can accomplish some of this type
    of thing with OpenSSH, but generally you have to run multiple
    instances of the server on different ports.

    + Exert finer-grained control over what kinds of SSH services you
    provide. You can forbid terminal access while still allowing sftp,
    for example, by simply rejecting the corresponding SSH protocol
    requests (shell and exec channels), rather than resorting to custom
    shells or other hacks that have unwanted side effects.

    + Control port forwarding with ACLs that include permit/deny statements
    and patterns matching user, target hostname, IP address, etc.

    + Require multiple forms of authentication for access (e.g. password and
    public-key).

    * SOCKS support for outgoing SSH connections (note this is different from
    the OpenSSH -D feature, which Tectia has also).

    * "chroot"-ed logins

    * integrated support for RADIUS authentication

    * Support for Windows-native Kerberos. Although OpenSSH can be built with
    Kerberos support on Windows (with Cygwin), it does not

  6. Re:Where to go from here? on Math Awareness Month · · Score: 5, Informative

    Some of my favorites:

    "Topics in Algebra" by Herstein

    "Topology" by Hocking and Young [Dover]

    "Counterexamples in Topology" by Steen & Seebach [Dover]

    "A Mathematical Introduction to Logic" by Enderton

    "Galois Theory" by Stewart

  7. Re:But are people comfortable with SSO! on Kerberos: The Definitive Guide · · Score: 4, Interesting

    Kerberos isn't designed for the Internet. You need to set it up explicitly for each trust domain on each client computer. So users can't just pull out their personal laptops and use them to log in...

    I'm afraid your entire point here is just technically false. Kerberos only requires host setup with if the host is a server; that is, to run a kerberized service on it, you need to establish a shared key for the service principal with the Kerberos system (KDC) and store it on the host where the corresponding server can find it (e.g. /etc/krb5.keytab). A Kerberos client can run anywhere and does not require a prior host connection with the realm at all. You *can*, in fact, do exactly what you describe here as impossible: connect your laptop to a network and type "kinit user@REALM" to get credentials, then use a kerberized application such as OpenSSH. The Kerberos software can find a KDC for "REALM" from the DNS (assuming the appropriate rr's are available). Note that this is secure despite the insecurity of the DNS in general, since Kerberos is a shared-secret system: since you share a secret with the KDC (essentially your password), you can validate the KDC's response.

  8. writing on What Do People in the IT Field Do for Side Jobs? · · Score: 5, Interesting

    One side job that doesn't have the problem of clashing with office hours is writing. Over the past few years, I have co-authored two O'Reilly books: "SSH, The Secure Shell (The Definitive Guide)" and "The Linux Security Cookbook." In addition to a substantial second income, I have had several follow-on writing and consulting opportunities (white papers, articles, etc.). Of course, there's the question of whether you want to spend even more time sitting in front of a computer in your off hours...

  9. Re:Writer and technical editer of computer books on What Do People in the IT Field Do for Side Jobs? · · Score: 1

    "editer"... "flush out"...

    Perhaps you should subcontract out the editing part.

  10. group theory on So You Think Physics is Funny? · · Score: 5, Funny


    Q: What's purple and commutes?

    A: An Abelian grape.

  11. Re:How is this not an abuse of power? on More on Massachusetts' Push for Open Source · · Score: 1

    shouldn't decisions based on taxpayer money usually be based on cost analysis?

    They should be based on sound analysis, surely, but cost is only one component. There are plenty of other extremely good reasons to prefer -- indeed, to demand -- open source in government. The following letter, purportedly from a Peruvian official to a MS exec, lays them out very well:

    http://www.theregister.co.uk/content/4/25157.htm l

  12. in the future on CNET News.com Turns 7 · · Score: 3, Funny

    ... in which he reflects on their founding slogan of 'Tech News First' and their commitment to that going forward... Thoughts or opinions, anyone?"

    I really hate that bit of idiotic business-speak, "going forward." We should all feel incentivized to leverage our existing linguistic infrastructure, and architect a solution using existing word-assets rather than repurposing them -- going forward.

  13. Re:What about port 25? on Should ISPs Be The Little Man's Firewall? · · Score: 1

    This is a shortsighted and ultimately ineffective approach to security.

    To point out one simple problem: when you mention "SMTPS," you are apparently thinking of SMTP over SSL on the alternate port 465. But this method of securing SMTP (and other protocols) is deprecated by RFC 2595, section 7, in favor of STARTTLS (and similar mechanisms). Requiring people to use a VPN to do such a simple thing as submit authenticated mail to a remote server is overly complicated, burdensome, and inappropriate.

    More generally, over time this approach simply won't result in better security, and you will have extra annoyance, complexity, and breakage with no upside. As long as you can exchange arbitrary bits between two hosts, in some way, there's a channel that can be multiplexed to do anything you like, and get around any exterior restriction. At first, this may result in some advantages, since only a small number of techies will know how to get around it. However, it is self-defeating. If it results in any significant inconvenience, a workaround will be codified into common software, and the restriction will shortly become meaningless. HTTP is a perfect example. Years ago, firewalls appeared which blocked all inbound TCP ports except HTTP -- the rationale being, HTTP is relatively harmless, most all it does is ask to see some files; configure the web server and file security properly, and what's to worry?

    Of course, then distributed computing models became more widespread, and people wanted to do things like send information as well as receive it, do RPC, etc. -- but the only port vendors could be sure would be open was 80. So they turned on PUT and invented things like DCOM and SOAP -- and now port 80 is just as dangerous to have open as if we had these various things on their own ports and had them all open; there is no difference.

    This process will just repeat itself. Security is not gained by blocking packets based on crude, low-level indicators like TCP port numbers. All you get is the same security problems you had before, only now with a network that is overly complex, difficult to use, and prone to breakage, because of all the random restrictions in place (unnecessary NAT, simplistic firewalls, etc.).

  14. Re:"theft" on "Stolen" SCO Linux Code Snippets Leaked · · Score: 1

    One of the more irritating tactics of posters with nothing to say is to attack a statement based on an interpretation they know to be wrong. It's like the Spelling Police

    You insinuate that I know my interpretation of the situation to be "wrong," but you have no credible personal basis on which to make that claim (since you are posting anonymously), and present no facts to back it up. Your post is hence without merit. As for what this could possibly have to do with correcting spelling, that's anyone's guess, but it doesn't seem very interesting...

  15. "theft" on "Stolen" SCO Linux Code Snippets Leaked · · Score: 3, Insightful
    Face it. There is stolen code in Linux. How much and how severe the
    value of the theft is to be determined but that there was theft is almost
    certain...


    One of the more irritating tactics in the war of misinformation about IP
    being waged by organizations like SCO, the RIAA, etc., is the intentional
    misuse of language. Things like trying to make "filesharing" a dirty word
    in itself, when in fact there is of course nothing more immoral about
    copying files than there is about using a photocopier -- it depends on
    what you're copying and what you're doing with it.

    Another example is the rampant incorrect use of the terms "theft,"
    "stealing," etc., intended to make the alleged perpetrators sound like
    sordid, common criminals. Copying a file, no matter what the IP issues
    surrounding it, is simply not "theft." From Webster's
    dictionary:


    Theft, n... (Law) The act of stealing; specifically, the felonious taking
    and removing of personal property, with an intent to deprive the rightful
    owner of the same; larceny.

    Note: To constitute theft there must be a taking without the owner's
    consent, and it must be unlawful or felonious; every part of the property
    stolen must be removed, however slightly, from its former position; and it
    must be, at least momentarily, in the complete possession of the
    thief. See Larceny, and the Note under Robbery.


    Copying data does not deprive the owner of the original of that data. It
    has not been removed, and he still has access to it and use of it. There
    might be copyright infringement, and there might not be, but it is
    not theft.

  16. some great books on Science and Math For Adults? · · Score: 1


    Five Golden Rules: Great Theories Of 20th-Century Mathematics -- And Why
    They Matter (John L. Casti)

    It Must Be Beautiful: Great Equations Of Modern Science
    (collection of essays, edited by Graham Farmelo)

    Mathematics: The Science Of Patterns
    (Keith Devlin)

    Beyond the Third Dimension: Geometry, Computer Graphics, and Higher Dimensions
    (Thomas F. Banchoff)

  17. stupid, stupid world... on Window Managers for High Resolution Displays? · · Score: 1

    It's hard to believe this is an issue in the year 2003. We've had good device-, resolution-independent graphics systems for decades (e.g. Display PostScript, NeWS, etc.). It is an obviously, profoundly stupid thing to do to measure anything for display, at a high level, in units tied to something as hardware-dependent as pixels. And yet, here we are, discussing this problem as if it were some kind of deep technical issue -- and people are afraid to buy better monitors because they have to squint at them, because the software running the displays of the major OS's still makes mistakes we learned how to avoid in the 70's.

    Our species is doomed.

  18. Re:$50 for solid security... on Linux Security Cookbook · · Score: 1

    a nice Linksys router.

    Open only the ports you need and make sure the software running on them is secure.


    This is a naive and misleading suggestion. First, you cannot "make sure" any software is "secure." Second, this does not address the myriad vulnerabilities inherent in the software people run every day which are not network servers: mail readers vulnerable to viruses, web browsers vulnerable to many kinds of malicious content, etc. For both these reasons and more, security must be a multi-level, ongoing process -- not just "set up a firewall and you're secure!"

  19. Re:Paranoia on Linux Security Cookbook · · Score: 1

    Another way to do that is to use RFC - Remote Filesystem Checker (look it up on freshmeat) which scp's a static binary of your IDS of choise to the machine that needs checking, runs it, and compares with the local DB of the 'trusted' machine. Much cheaper than buying specialized hardware.

    Much cheaper, and not at all the same thing. This is not equivalent, which is made clear in the sequence of examples in the book of which this is an excerpt. "Copying over a static binary" does not guarantee it will do what you want, since if it's hacked the machine in question may have had its kernel or program loader altered so that the "binary" does not do what you think it will. Or the tool you use to "copy [it] over" may have been altered, or the network traffic involved in comparing the local and remote signatures may be compromised. Etc. You may consider these unlikely attacks, and I agree, but they are possible, and this recipe is at the higher end of paranoia attempting to address these possibilities.

    Of course, if the running kernel has been altered without changing any disk files, then you've really got a problem...

  20. where are the editors? on Bookseller Purges Records to Avoid PATRIOT Act · · Score: 0, Redundant

    ... sidestep typically insideous a provision...

    Um, how about: ... sidestep a typically insidious provision...

    OK, this is absurd. Judging by the general arrogance level, poeple who post to Slashdot obviously think of themselves as pretty smart. It's not very convincing, when the editing, spelling, grammar, etc. in the posts is so consistently bad! And do the Slashdot folks really think their publication can be taken seriously, when it's apparently edited by a bunch of not-very-well-educated 6th-graders? Wake up.

  21. Re:Homophobia on Some Geek Guides for Dating · · Score: 2, Informative

    Maybe that in a forum mostly used by men, we have a total and absolute disgust of other men who suck another man's dick or to fuck another man in the ass.

    Maybe you do, but then you've got some kind of weird hangup. I think it's more likely that "we" have disgust for people who think like you... fortunately though, your brand of intolerance is fading away.

  22. Re:Not Really on Your Eyes Will Melt Out Of Your Head · · Score: 1


    or is that something that distinguishes a real nerd from the avergae joe computer user: the ability to withstand prolongued exposure to CRTs...


    Or perhaps, merely the stupidity required to subject oneself to same.

  23. Re:nVidia gForce 4 Ti is working for me on Using Apple's 23" HD Cinema Display on PCs? · · Score: 1

    Success!

    To make a long story short -- I had to upgrade the BIOS. After that, the
    nVidia board worked perfectly.

    Thanks for all the input; without the assurance that these cards did
    actually work in this setup, I would not have gone back and done the extra
    testing/searching that turned up the solution.

  24. Re:nVidia gForce 4 Ti is working for me too. on Using Apple's 23" HD Cinema Display on PCs? · · Score: 1
    It's encouraging that you both got this to work with this (relatively
    inexpensive) card; however, I'm puzzled why I didn't work for me. As I
    said, I did try the Xtasy nVidia GeForce4 Ti. I got no picture at all,
    ever -- just single glimpse of a blinking cursor at power-on, which
    immediately disappeared, then a blank screen. I also got this response
    from VisionTek support (the card maker):

    GeForce4 Ti4600 which used on Apple computers has different design then
    Ti4600 for PCs. For PC, the maximum supported resolution for DVI is
    1280x1024.
    ... but since you are both claiming it works, I suppose I will discount
    this. Are you using AGP or PCI?

    I know about the monitor control issue, but since I have a Mac connected
    also, this isn't a problem...

  25. Re:DVI-ADC on Using Apple's 23" HD Cinema Display on PCs? · · Score: 0, Redundant

    As is perfectly obvious from my post, I already have this converter, otherwise I couldn't be driving the display with my TiBook.