Sending faxes over VoIP seems to be rather problematic. Most of the CODECs are optimized for voice, not for the frequencies required by fax machines. The solid answer seems to be time upon time that faxes simply does not work over VoIP. I can confirm this – especially when using the g729 codec as required by most of the carrier grade VoIP providers for which ULS is a reseller. Yet, many people still have stacks of pages which they don’t first want to scan and then send off to a email2fax service, so what to do?
Archive for the ‘IT’ Category
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Wednesday, July 23rd, 2008Atheros AR242x
Friday, July 18th, 2008Ok, so the wireless bug has finally bitten me and I’m now trying to make my wireless work. I already understood why people said wireless in Linux is a pain (and this is one of the reasons why there is always an abundance of network cables that travels as part of my computing kit).
My wireless card is identified by lspci as an AR242x Atheros card, and as it turns out, there is some elementary support for this card in the madwifi-ng drivers if you’re running an old enough kernel – which I’m not. And the ath5k driver loads, identifies the card and even creates a wlan0 device, and I can set all the different parameters – it just turns out it doesn’t actually perform any Tx/Rx at all!
So after googling a bit and looking on the projects page it turns out that this is exactly the state of the current ath5k driver. I’ll grant that it’s better than what it was under the 2.6.25 kernel (first to have the ath5k module in the tree) at which point the card didn’t even register, and in actually got confused to the point where the switch would no longer switch on/off the LED indicating that it’s active. It’s also leagues ahead of the madwifi-ng drivers that doesn’t even compile against my 2.6.26 kernel (error: implicit declaration of function ‘__skb_append’, svn snapshot at r3366+ar5007), or using ndiswrapper – which simply oopses the kernel and causes a kernel panic (on my notebook at least).
I’ve been looking for an excuse to get my hands in the kernel for a while again – I’m guessing this is it.
UPDATE (2008/07/18): Turns out someone already jumped me on this and that the 2.6.27 kernel will have the proper driver merged. The correct versions can be downloaded from http://www.kernel.org/pub/linux/kernel/people/mickflemm/. What I’ve done is remove all but CONFIG_WIRELESS_EXT from my 2.6.26 kernel image, and then ran make in the extracted compat-wireless sources after which make install as root did the trick. There still seems to be some instabilities (had at least one kernel panic when I tried to rmmod the ath5k/mac80211/cfg80211 modules), but it seems to be working pretty well, at least against my MikroTik RB433 RouterOS 3.10 setup.
DNS Lists, Greylisting and other SPAM related stuff
Wednesday, July 16th, 2008We all hate receiving SPAM. It’s simple, someone sends you a load of junk mail (be it the common VIAGRA spam or more targeted SPAM from companies using mailer lists) and you receive it and you spend about 10 seconds to decide it’s junk before deleting it. So today ISPA had a “conference” of sorts, called the SpamJam II. Quite a few questions were raised, and some answers provided. And actually some stuff which I’ve been thinking about the last couple of days was under heavy discussion.
Building a DUL on demand
Wednesday, July 16th, 2008A DUL or a Dial-Up-List is a DNS list that gives an A record (usually in the 127.0.0.0/24 range) for IPs that’s dynamically assigned, such as dial-up users, or various DSL services. Basically, any technology where an IP is not assigned to a specific person (3G, iBurst, ADSL, sentech, dial-ups).
What the question is now, is whether it’s possible to build such a DUL based on the information provided in whois. (more…)
