May 17th, 2009 §
Wolfram Alpha is a knowledge engine (It’s not a search engine or a google killer) which finds and calculates information for you. There are thousands information sources which it queries and provides very concise, but detailed answers.
Give it a go, I can find this being super handy for my uni studies. Wolfram|Alpha The only thing it’s missing is a short name.
March 7th, 2009 §
The hardest part of the install was working out it’s partitioning tool and not getting it to touch my second drive, which had Windows and backups on it. I did finally get it to work, but for some reason it thought 15GB was enough room for me. That’s not a huge problem because I just extended the LVM after the install.
Once install, installing the ATI drivers using the one click installer was wonderful (however I did have to click more than once). Compiz fusion was easy enabled and networking (WPA) was a breeze to setup in YaST. The general look and feel wasn’t quite right, so as usual I modified to my liking.
OpenSUSE for me has achieved my goal as the required amount of terminal use is minimal. I have installed several apps without any problems and it’s been wonderful to use.
February 9th, 2009 §
TCP has lots of features, like error recovery and acknowledgment which UDP doesn’t support. Both use “ports” and both have error detection. So why use UDP?
I’ve linked to a flickr scan of TCP header. As you can see a TCP header is 20 Bytes long, without it’s payload, where as if you look at a UDP header it’s only 8 Bits long. UDP already has the advantage of being smaller in size, but what really makes UDP useful is it’s lack of error recovery.
In services like VoIP , Video Conferencing and Gaming, by the time TCP has detected an error, sent a request for the missing packet, and continued on it’s way it has interrupted the call, making TCP a bad choice. Since UDP doesn’t have error handling, it doesn’t matter if a packet was lost or damaged, because UDP won’t request (or check) for the missing packet and continue on it’s merry way. Thus keeping the call at low latency.
Ps. Now that I have gotten half way through the first Cisco CCNA book I might share a few other network tips, tricks or info.
January 31st, 2009 §
With VoIP moving to home users now problems occur with keeping calls going when other home users are download or the like. Newer modems support QOS but still suffer from a simple flaw which impacts the usefulness of it. These modems can only control QOS for outgoing packets (uploads) and not incoming, becuase the QOS needs to be done on the ISP switches/routers. This flaw means that if someone packet floods your connection, QOS won’t be able to help your VoIP system.
There isn’t really a simple fix to this, however it would be nice if ISPs had a configuration page or the like to allow you to make simple QOS rules. Some people will want QOS on VoIP IPs/ports and others will want it on other services.
October 28th, 2008 §
Hardware wise it’s just a 1.8ghz, 512mb of RAM, gigabit network card and 20GB hard drive. I’ve added a 40GB hard drive and a 320 GB hard drive for the moment to play with.
It’s quite a nice and quite server and I have ordered a 1TB hard drive and SATA card for the server, from Jack, which will provide me with a decent amount of storage.
Software wise I’ve been trailing Openfiler for the server which is an amazing file server bundle that runs on rPath linux. It uses all the new linux hard drive stuff, like LVM and software RAIDs, and has HTTP, NFS, RSYNC, FTP and SMB support for protocols, which is really nice.
The interface for openfiler is just awesome. You can easily add new partitions, and take snapshots of drive. You can manage all the access rights and everything from the web interface. It’s really really nice.
It still needs a bit of work, I had to hit the terminal a few times to fix some bugs, add new users and resize some partitions. The instructions for install are a littler unclear, like when your partitioning, I don’t think you are ment to partition the parts you want to share.
I don’t like the fact it runs on rPath linux and the way it’s made only for rPath, as this means that you have to have a dedicated server for files and nothing else. Most of the time my file server will be idle so I may aswell make it do something else.
It’d be really nice if it was just a package like software, like a gentoo ebuild or a deb package. That aside it’s really nice software and worth a look at.
As for backup software for Windows Vista, it really does suck. The Vista backup tool tries to backup your whole drive, which I don’t want it to do, and it doesn’t back up everything, just documents and the like, which is really annoying. On the other Vista machine I’ve used SyncToy from MS which is a nice piece of software, and so far it has been working well.
I’ll trial these and report back at the end of the testing period.
