Posts Tagged ‘geographic location’

Improve your night sleep when using PC with Windows XP late at night with F.lux

Tuesday, February 26th, 2013

f.lux auto detect timezone geographic location after install screenshot microsoft windows XP

After testing F.lux on Mac OS X, I decided to install it and test it on a friend's Windows XP OS. Up is a screenshot from the program right after installed.

Just like on MAC OS X F.lux auto set the Geographic Location and started changing the Gamma of the screen to reddish at night. As you can see the change of Screen Color gamma can be set in various intervals with default of auto changing monitor backlid gamma every 20 secs.

On early day, when usually outside you see the day light because Sun Light shines on our planet, the color gamma is auto-configured to the normal light one.
I think in short future all computer vendors should think of embedding F.lux or some similar application to every Desktop PC, laptop, Phone and Tablet.

f.lux settings improve night sleep auto set monitor gamma ms windows xp

When F.lux is active a tiny icon with the F.Lux logo is visible on Taskbar like in below screenshot. From there you can view f.lux settings, see in what Color gamma mode the program works at present or to manually set custom color gamma. Enjoy

Improve night sleep with F.lex on Mac OS X, iPhone and iPad

Monday, February 25th, 2013

f.lux application change screen color gamma to sleep better when using computer late at night macOSX and iphone
Recently I blogged about how to reduce night sleep problems and diminish insomnia on Linux with little command line tool – redshift. Now I'm in a friend who is a Mac user and since he had lately problems with sleeping. I remembered about redshift and one other tool which I read about called F.lex. We give it a try and installed it on his Mac OS X Lion – ver (10.7.5). Installation is like other standard Mac OS X applications, download f.lux version for Mac OS then click  .DMG binary and you're asked if you want to install the program in Mac active Applications. That's all the program is installed and you don't even need to configure it as the program automatically determines Time Zone / Geographic Location  configured for OS X. Once installed you will notice the F.lux switching screen gamma icon on left of Mac panel:

sleep better when using Mac laptop at night with F.lux

In F.lux configuration, by using Search button the program can automatically determine Geographic Location, however if you it fails to determine proper location and improperly sets the screen color gamma, you can manually set location coordinates. F.lux tunes screen color gamma accordingly to day or night and time in day. If it is night it makes the screen reddish, so eyes our eyes relax strain (stress) and our organism prepares to get to bed so once you're in bed it is easier for your brain to get asleep.

F.lux screenshot on Mac OS X Lion improve night sleep insomnia

Now here it is 23:37 at Night and F.lux smartly changed the color gamma accordingly to night mode (reddish) gamma. I've noticed on F.lux's website there is version for iPhone and iPad

How to check the IP address of Skype (user / Contacts) on GNU / Linux with netstat and whois

Thursday, May 3rd, 2012

netstat check skype contact IP info with netstat Linux xterm Debian Linux

Before I explain how netstat and whois commands can be used to check information about a remote skype user – e.g. (skype msg is send or receved) in Skype. I will say in a a few words ( abstract level ), how skype P2P protocol is designed.
Many hard core hackers, certainly know how skype operates, so if this is the case just skip the boring few lines of explanation on how skype proto works.

In short skype transfers its message data as most people know in Peer-to-Peer "mode" (P2P)  – p2p is unique with this that it doesn't require a a server to transfer data from one peer to another. Most classical use of p2p networks in the free software realm are the bittorrents.

Skype way of connecting to peer client to other peer client is done via a so called "transport points". To make a P-to-P connection skype wents through a number of middle point destinations. This transport points (peers) are actually other users logged in Skype and the data between point A and point B is transferred via this other logged users in encrypted form. If a skype messages has to be transferred  from Peer A (point A) to Peer B (Point B) or (the other way around), the data flows in a way similar to:

 A -> D -> F -> B

or

B -> F -> D -> A

(where D and F are simply other people running skype on their PCs).
The communication from a person A to person B chat in Skype hence, always passes by at least few other IP addresses which are owned by some skype users who happen to be located in the middle geographically between the real geographic location of A (the skype peer sender) and B (The skype peer receiver)..

The exact way skypes communicate is way more complex, this basics however should be enough to grasp the basic skype proto concept for most ppl …

In order to find the IP address to a certain skype contact – one needs to check all ESTABLISHED connections of type skype protocol with netsat within the kernel network stack (connection) queue.

netstat displays few IPs, when skype proto established connections are grepped:

noah:~# netstat -tupan|grep -i skype | grep -i established| grep -v '0.0.0.0'
tcp 0 0 192.168.2.134:59677 212.72.192.8:58401 ESTABLISHED 3606/skype
tcp 0 0 192.168.2.134:49096 213.199.179.161:40029 ESTABLISHED 3606/skype
tcp 0 0 192.168.2.134:57896 87.120.255.10:57063 ESTABLISHED 3606/skype

Now, as few IPs are displayed, one needs to find out which exactly from the list of the ESTABLISHED IPs is the the Skype Contact from whom are received or to whom are sent the messages in question.

The blue colored IP address:port is the local IP address of my host running the Skype client. The red one is the IP address of the remote skype host (Skype Name) to which messages are transferred (in the the exact time the netstat command was ran.

The easiest way to find exactly which, from all the listed IP is the IP address of the remote person is to send multiple messages in a low time interval (let's say 10 secs / 10 messages to the remote Skype contact).

It is a hard task to write 10 msgs for 10 seconds and run 10 times a netstat in separate terminal (simultaneously). Therefore it is a good practice instead of trying your reflex, to run a tiny loop to delay 1 sec its execution and run the prior netstat cmd.

To do so open a new terminal window and type:

noah:~# for i in $(seq 1 10); do \
sleep 1; echo '-------'; \
netstat -tupan|grep -i skype | grep -i established| grep -v '0.0.0.0'; \
done

-------
tcp 0 0 192.168.2.134:55119 87.126.71.94:26309 ESTABLISHED 3606/skype
-------
tcp 0 0 192.168.2.134:49096 213.199.179.161:40029 ESTABLISHED 3606/skype
tcp 0 0 192.168.2.134:55119 87.126.71.94:26309 ESTABLISHED 3606/skype
-------
tcp 0 0 192.168.2.134:49096 213.199.179.161:40029 ESTABLISHED 3606/skype
tcp 0 0 192.168.2.134:55119 87.126.71.94:26309 ESTABLISHED 3606/skype
...

You see on the first netstat (sequence) exec, there is only 1 IP address to which a skype connection is established, once I sent some new messages to my remote skype friend, another IP immediatelly appeared. This other IP is actually the IP of the person to whom, I'm sending the "probe" skype messages.
Hence, its most likely the skype chat at hand is with a person who has an IP address of the newly appeared 213.199.179.161

Later to get exact information on who owns 213.199.179.161 and administrative contact info as well as address of the ISP or person owning the IP, do a RIPE  whois

noah:~# whois 213.199.179.161
% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See http://www.ripe.net/db/support/db-terms-conditions.pdf

% Note: this output has been filtered.
% To receive output for a database update, use the "-B" flag.
% Information related to '87.126.0.0 - 87.126.127.255'
inetnum: 87.126.0.0 - 87.126.127.255
netname: BTC-BROADBAND-NET-2
descr: BTC Broadband Service
country: BG
admin-c: LG700-RIPE
tech-c: LG700-RIPE
tech-c: SS4127-RIPE
status: ASSIGNED PA
mnt-by: BT95-ADM
mnt-domains: BT95-ADM
mnt-lower: BT95-ADM
source: RIPE # Filteredperson: Lyubomir Georgiev
.....

Note that this method of finding out the remote Skype Name IP to whom a skype chat is running is not always precise.

If for instance you tend to chat to many people simultaneously in skype, finding the exact IPs of each of the multiple Skype contacts will be a very hard not to say impossible task.
Often also by using netstat to capture a Skype Name you're in chat with, there might be plenty of "false positive" IPs..
For instance, Skype might show a remote Skype contact IP correct but still this might not be the IP from which the remote skype user is chatting, as the remote skype side might not have a unique assigned internet IP address but might use his NET connection over a NAT or DMZ.

The remote skype user might be hard or impossible to track also if skype client is run over skype tor proxy for the sake of anonymity
Though it can't be taken as granted that the IP address obtained would be 100% correct with the netstat + whois method, in most cases it is enough to give (at least approximate) info on a Country and City origin of the person you're skyping with.