Public & Private streams

Most people using social media do not mind sharing certain information. Take for example sharing of news items, most people probably wouldn’t mind if others could “follow” them and also get the news. Or you could be a private person and only want to share data with your friends, or you could be a journalist wanting to share everything you post.

In my view these are two distinct things and should be treated as such. Private streams allow for pushing content, or some sort of publish-subscribe mechanism. While public streams are more suited to be served on a location and then pulled by anyone who wants it. One could even consider sharing a public stream as a static file (in for example json format) and just updating this as one posts something to the stream. Etag checking would then avoid unnecessary transfer and otherwise the webserver is just serving a static file which is cheap.

Private streams on the other hand would benefit from a publish-subscribe approach since that would require minimal data transfer and people would get the data as soon as it is available. However a side effect of the publish-subscribe mechanism is that the publishing peer has to keep track of send data (and is that really what you want?). However this could be simply solved by each peer keeping a list of last update (unix timestamp anyone) of all his peers and then do some communication once a peer comes online or when an update is posted and decide what to communicate.

Specify the communication not the implementation

Keeping the open spirit the communication should be specified and not the implementation. Many people do not want to (or can’t) run RoR however anything that can be implemented in RoR can also be implemented in an other language. When specifying the communication anyone can implement it, be it in RoR, php, C, asembly whatever…

Encryption

The whole idea of distributed social media is that you are in control of your data. So you probably do not want to send your (private) stuff in plain text over the internet. So it makes sense to use some sort of encryption to transfer the data. However that does not quaranty privacy. A lot of people do not have their own server running, and probably a lot of peers will be hosted on the same server. Now would you want the hosting company to be able to read all your private data? Of course not!

So the data should also be encrypted on your peer. GPG encryption could do this. That only on a host where you have your private key that you can decrypt the messages. Now I do understand that this brings certain complications. Then I would only be able to read messages on my laptop, in order to read (or send) messages on my phone I would need to copy my private key to my phone, which might not be what you want.

Another down side of this approach is that you can’t view or send messages when you are at someone else’s computer…
You could of course store your private key on the machine that hosts your peer instance but then anyone that could read your key (sysadmin or even more people due to a potential security bug) could get their hands on your private key, which is certainly not what you want.

Anyone else any idea’s on distributed social media?

Installing the printer on my girlfriends windows machine was relatively straight forward, but I still do not uderstand why I would need a 50mb download for some printer drivers?

Installing on my laptop was also made easy thanks to hplip. However I could not print! My cups log had the following message:

/usr/libexec/cups/backend/hp failed

Which is not that clear at all. Enabling debug loglevel in cups did not make things any clearer. After a lot of googling I found someone suggesting to install avahi. Which indeed is the solution!

So now I am happily printing! And will not try to get scanning up and running

Like I was saying after upgrading to version 0.4.11 I decided I wanted to close port 8080 (the one sabnzbd is using) to the outside word. Now I know apache has some nice proxy functions so it should be easy.

Make sure apache is compiled with the following modules: apache2_modules_proxy apache2_modules_proxy_http apache2_modules_proxy_balancer

That was the hard part. Now just add a vhost:


ServerName yourserver.com

order deny,allow
deny from all
allow from all
ProxyPass http://localhost:8080/sabnzbd/
ProxyPassReverse http://localhost:8080/sabnzbd/a

ErrorLog /var/log/apache2/error.sabnzb.log
LogLevel warn
CustomLog /var/log/apache2/access.sabnzb.log combined



This assumes that you have sabnzbd listening on localhost:8080. Now you probably do not want the whole world watching your downloads (or deleting them or whatever). So we just add some basic apache authentication, use htpasswd2 to create a file with authorized users and add the following lines into the location block.


AuthName "Login Required"
AuthType Basic
AuthUserFile <>
require valid-user


That is all.
Happy downloading!

First of all why is this a Warning? I mean I know I pressed Send. And besides that if it is a waring they should provide me with contact information on how to get my submission removed.

Now apart from the warning box it could be a message telling me everything is inserted into the database. Let say they have some java script in the background that does that and once everything is inserted it gives the warning (still a warning is wrong but OK). However I checked the source of the site and guess what? All the button does is generate the pop-up after which the stuff is submitted.

Now I’m wondering why people do this? It does not look good, since it is a wrong pop-up box. It does not speed up the process. It is wasting my time. Which in general I do not like.

Checkout my bash.org rss feed. It updates every 15 minutes. Enjoy

They their projector popped into my head. It has an USB-port. My laptop has an USB port. It did not take me to long to find out that I could do some nice things whit that. Acer has some software under windows. I was hoping they would have just posted the protocol online. But no. Ofcourse not. After browsing the Acer website and google. I could not find anything usefull about what command to send to the Projector (it does not help that Acer also creates a whole lot hardware).

So It was time to hookup my Laptop to the proejctor. Everything still works. And I was monitory /dev for any changes. The first thing to catch my eye was a bunch of new stuf in /dev/input. A mouse was automatically recognised. And it even worked. Moving some sort of analog stick around made my mouse move! Isn’t that magical!

However it is nice and all that I can use it as a mouse but who really cares? Now also tty12 was created. Which seems a lot more interesting. However I had ofcourse no idea what to send to the Projetor in order to get response. Now maybe I’ll hijack a Windows Laptop tomorrow and sniff some of the command send trough the USB port.

Ah well a nice project to work on during this vacation.

So 2 days ago something was wrong with the network. Don’t ask me what but it just was. All of the sudden no 10 mbit line. No it seemed like I was back at my old 56k6 modem. Damn. Pages not loading instantly. Man that is a pain in the ass. I had totally forgotten what it is like. That grabbing the source code for a random package can actually take more tan 1 minute or so :S

Well it is fixed now and I hope it won’t happen again.

Now I wanted to share some extra stuf on the server. For example the music, some files, photo’s etc. In windows they are all mounted. So I wanted to do the same on my linux boxes. Should be a piece of cake since a have a share dir on the server that holds all the stuff to be shared.

So I shared that dir via NFS. Mounting went easy. However. all the dirs were empty… Now why is that? Could it be some kind of dark magic? No it is just that NSF (for security probably) can only acces 1 partition per share. So now I have them all shared seperatly. Not a big deal ofcourse. BUt always good to know.

Now something else. The laptop is send with TNT, the post service in Holland. Now they have a nice track and trace system which allows me to enter the barcode and the postal code and well I know “where” the package is. However for some reason they do not have an rss feed on that. That would be something which it is perfect for. Ah well… I’m not sending packages that often… but still

But as it isn’t supposed to get jammed we had to get the screwdriver out. So after taking almost every screw out of the printer we finally got the part where the paper was jammed. A lot of poking and torning later all the paper was gone and we could put the printer back together. Now the whole point of this story is…

A printer always finds a way to get the paper jammed.