Computer Tips -Tech Info

Tag: ISP

  • AT&T rbl block inquiry site

    First, I guess I should give a primer, what’s an RBL? RBL stands for Realtime Black List (or Realtime Block List depending on who you talk to.) The idea is there are machines that either 1) have no business DIRECTLY trying to deliver a mail message to a legitimate mail server or 2) are known to spew out junk mail, or viruses or other bad content. So, many service providers make use of blacklists to decline messages from suspect machines. In some cases these lists are cultivated in house, in other cases people make use of various publicly available lists online.

    But…

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  • More postfix spam blocking….

    Postfix has a NUMBER of tools for rejecting unwanted messages before they get in the door and waste your CPU time on deciding “hey this mail is spam”. Up until recently I’ve mostly used the relays.ordb.org check (which in the last couple months has now gone defunct.) When we started noticing problems with ordb.org’s responsiveness I planned to investigate other blacklisting options and found several. Obviously there are advantages and disadvantages to blacklisting. The first disadvantage is you have turned over control of blocking mail senders to an outside authority and you should familiarize yourself with THEIR policies for listing (and delisting) a server.

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  • Privacy concerns abound…

    Well, the weekend saw news stories of Google planning to eavesdrop over pc microphones to hear what you’re watching on tv to target ads….. (I’m not holding my breath on that one, but… I do know how to disconnect the microphone.) Also, there was the story of Browzar which was supposedly THE solution for private web browsing…. well, it turns out it set’s it’s own search engine as the default and uses your search information to give sponsored links. Sans also mentions that the last visited url may be saved to disk as well. Really, we have several places where information is kept on us anyway (ISP/etc.) But, if you’re really concerned about private browsing you might try out the vmware browser virtual machine (or a portable web browser on a usb-key.)

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  • Google roundup…. 55 ways to have fun, ipv6 and schoolkids Social Security Numbers….

    There are a few Google related stories of the last few days to catch up. 1)55 Ways to have fun with Google is an e-book available for purchase on Amazon or Lulu.com, but it’s also avaiable as a free pdf download. (And it’s licensed so you can mix it up/etc…) It’s certainly not as deep as a Google Hacks overview would be, but covers some of the Google games out there and a few other interesting bits as well. It might be a good gift for those just getting their feet wet in Google searching…. 2) There are a couple stories about just how many IPv6 addresses that Google controls these days. From George Ou’s article ” (79 billion billion billion addresses)”…. They’ve been sold that many, really for the main purpose of being an ISP of some sort (maybe selling businesses IPv6 connectivity?)

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  • Net nuetrality and the changing of the web as we know it

    Not too long ago I had an article about an ISP/telecom executive that floated the idea of charging some BIG web sites to make sure they had a fast connection/delivery to the ISP’s customers. In effect, they would prioritize traffic for the bigger websites that were able to pay for the added benefit. Those that didn’t pay would have slower access by the ISP’s customers. One of the questions I floated at the time is what if someone has a politically unpopular site, and no money, are they dropped into the slow lane/ How slow? Maybe a political candidate…? This has potentially bad implications…

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  • What a week….

    I think it’s time to pass along a long story of what’s gone on over the last week or so here and some of the reasons there hasn’t been anything posted. Generally, I would say that work has been busy, but something happened last week that went a bit beyond the day to day and there might be some items worth considering. The short story is my internet access was suspended and I’ve been only connected to the internet for 30 minutes or so at a time to retrieve mail and spent dozens of hours reviewing system logs…. but the long story is needed to sort out what has happened. I’m not going to break this up into multiple posts, but I may pull out some details for seperate posts at some point.

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  • Network Security guide for the home or small business network – Part 17 – The Security Mindset

    This may be one of the most important entries in this series. An important defence against those that would try to access your network is to constantly have the “security mindset”. Ask yourself “do I need this, how could it be exploited, what are the implications of this”… When it comes to people asking you to click on a link… “do I trust the person, am I sure it’s from the person that it claims to be… how sure? is it normal behavior for this person to ask me to click on a link?” I guess what it comes down to is developing some healthy critical thinking and skepticism…

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  • Network Security guide for the home or small business network – Part 11 – Why?

    Alright, so you’re still reading this series and you’re thinking. Look, I’m not protecting national security secrets. All I’m doing is (running a business|emailing my grandkids|using the web for research).

    True, good point. You’re not at the defense department. OK. Let’s say you just use your computer for email and web browsing. That’s low priority stuff right? No sensitive information on your PC? Do you ever do banking online? Yes – then you should be concerned… No? You should still be concerned… here’s why…

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  • Interesting vector for browser vulnerability exploit…ebay

    incidents.org has received a tip on an ebay item that contained some malicious script…

    ISC reader Gareth Attrill pointed us to an eBay auction that has some escaped HTML code that sneaks in a link that tries to get a trojanized .jar (usage.jar) file loaded on anyone who loads the listing. The latest .dat for McAfee immediately detected (and deleted) the code as Exploit-ByteVerify. The lister most likely managed to bypass other protections that otherwise prevents this kind of code from being inserted into item listings. Both eBay and the ISP that is hosting the malware have been notified.

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  • Online music locker

    The Oboe service has launched. It’s a project that Michael Robertson of Mp3.com and Lindows/Linspire fame has been building interest in for the last 6 months or so. (Maybe a bit longer). The idea is that for a $39 per year subscription you can have an unlimited amount of space online to store your music files (.mp3, .wma, .ogg or .acc are autodetected in download links by the firefox plugin.) Then you can stream them anywhere. What’s interesting about the browser plugin is – let’s say you’re buying a track at the web site of whichever online music store, an icon appears next to the download link, you click and it “sideloads” the file into your online storage locker (bypassing the step of downloading to your pc, then uploading to the storage locker.)

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