Accessing Amazon Web Service MySQL Database using phpMyAdmin

Amazon Web Service currently offers one-year-free trial of their services and I am experimenting with their database service. I set up a MySQL server database. However, after the service was ready, I found out that, AWS doesn”t provide GUI to access the database. I always use phpMyAdmin to manage MySQL database because it is easy and thinking whether I could use phpMyAdmin to manage my AWS database or not. After a quick research on the Internet, I found out that it is possible. How could we do that?

First, we need to install phpMyAdmin. The good thing about phpMyAdmin is it is a web application, doesn”t matter the type of Operating System you have as long as it has web server to host phpMyAdmin you are set. Second you need to modify phpMyAdmin configuration file by adding few lines on it. The file that you need to modify is config.inc.php. Different OS has different location for this file. I used Ubuntu 14.04 and Windows 7 XAMPP.

  • Ubuntu 14.04 –> /etc/phpmyadmin
  • Windows 7 XAMPP –> \xampp\phpMyAdmin (relative to your xampp root document by default it is in C:\)

Add these following lines inside the php tag of config.inc.php

/*You need the following line define the next server configuration.
If you find this at the end of your configuration you don"t need to add it*/
$i ;
/*This line is optional. It is used to name your connection*/
$cfg["Servers"][$i]["verbose"] = "Amazon Web Service";
/*Defining authentication type*/
$cfg["Servers"][$i]["auth_type"] = "HTTP";
/*Fill in the host with your AWS instance endpoint information*/
$cfg["Servers"][$i]["host"] = "xxxxxxx.cnbvmxbgsmon.us-west-2.rds.amazonaws.com";

Once you added those lines, save the changes and you are all set. Now run your phpMyAdmin page from your browser and you will start seeing drop down menu of server options you wish to connect to like the figure below.

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Accessing Amazon Web Service MySQL Database using phpMyAdmin by Rio Indra Maulana is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
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QAM Modulation Technique: Concept, Challenges and Solutions

The new 802.11ac standard from IEEE, is currently penetrating wireless network markets with its new features and technology. Watson (2013), Public Marketing of Meru Networks, claims the 802.11ac standard will be able to provide a maximum client data rate per radio of 1.3 Gbps. How does it manage to achieve those higher bandwidths compared to the last standard? One part of this technology that makes it possible is the complex modulation technique that 802.11ac employs which is 256-QAM. This modulation technique is a combination of phase-shift keying and amplitude-shift keying. QAM itself stands for quadrature amplitude modulation. In order to understand how 256-QAM could give higher bandwidth we need to know how QAM works.

The QAM works by modifying either amplitude, phase or both. For example in 4-QAM (commonly known as QPSK) the only attribute which is modified is the signal phase. Thus, it gives four combinations which are 00, 01, 10, 11 or we can say each wave can carry 2 bits.

4-QAM Constellation Map

As we can see from the figure above, it has the same amplitude (one circle) but four different phases. Meanwhile in 16-QAM, it modifies both amplitude and phase that will result in 16 combinations. this means that each wave can carry 4 bits (24 = 16). By increasing the complexity of phase-amplitude combinations, it will also increase the number of bit it carries. Since 802.11ac employ 256-QAM, it means that each wave could carry 8 bits (28 = 256) which is faster than 16-QAM.

16-QAM Constellation Map

This means that the higher the modulation the better the carrier signal is since it can carry more bits. Ian (n.d.) explained that the more complex the modulation degree is the less resilient the signal will be to noise and interference. This is true because in higher levels of modulation, signal is packed and the boundary between one amplitude or phase with another is very small and little interference might cause the receiver to misinterpret the signal. However this problem can be easily overcome by increasing the power of signal which means increasing the amplitude so it will enlarge the boundary between amplitude and phase which in turn will make the signal more resilient. However this solution also brings a disadvantage; since we increase the power of the signal it means that we will need a lot more power for transmitting the signal. By doing that it will drain the battery power quickly if it were to be used in mobile devices such as smart phones or laptops.

Ian (n.d.) explained another method to address the problem by using dynamic adaptive modulation, which is provided in most recent wireless devices. This type of system will examine the surrounding wireless environment to decide the type of modulation it must use to send the data. If it is possible to use the highest modulation, it will. If there are too many noises and interference the transmitter will then use a lower modulation that is more resilient to send the data.

In summary, 802.11ac is the network standard that will bring wireless networks to the next level, but in its development it has faced many challenges since it uses higher level modulation 256-QAM. It has to be able to maintain the signal resilience against noise and interference as well as maintaining power usage as minimally as possible. There are also other features of 802.11ac which is not covered in this writing that can address problem described above. The resource is a good start to gain more information about other 802.11ac features.

Resources

Poole, Ian. (n.d.). Comparison of 8-QAM, 16-QAM, 32-QAM, 64-QAM 128-QAM, 256-QAM, etc. Retrieved from http://www.radio-electronics.com/info/rf-technology-design/pm-phase-modulation/8qam-16qam-32qam-64qam-128qam-256qam.php

The New 802.11ac Standard: 256-QAM Explained [Video file]. Retrieved from http://www.youtube.com/watch?v=NbrRGBRk5fM

Watson, Richard. (2013, July). Understanding the IEEE 802.11ac Wi-Fi standard: preparing for the next gen of WLAN. Retrieved from http://www.merunetworks.com/collateral/white-papers/wp-ieee-802-11ac-understanding-en

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QAM Modulation Technique: Concept, Challenges and Solutions by Rio Indra Maulana is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
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My First Stargazing Report

Well, actually I stargazed before, but I didn”t do that to really observe stars and constellations. This time was my first time stargazing as a beginner in Astronomy (learning Astronomy is part of my new year resolutions). It was Monday Night, January the 6th of 2014. I started to stargaze around EST 9.00 pm until 10.00 pm. It was cold in Syracuse since the temperature was -12 degree of Celsius, and the wind, that made the weather colder, blew with the speed of 50 kph.After days of studying the book that I just got (Nightwatch), hours of constellation and stars reading from simulation software called Stellarium and days of cloudy night, I got my chance to try my newly acquired skill because Syracuse”s sky was very clear that night.

The first object I recognized that night was the belt of the great hunter Orion which consist of three aligned stars. Alnitak, Alnilam and Mintaka. Those three stars were named by Moslem”s astronomer, Alnitak and Mintaka means the belt while Alnilam means the arrangement or pearl. The name is pretty beautiful isn”t it? it is like a real belt which its arrangement (Alnilam) located in the middle of the belt (Alnitak and Mintaka). Alnitak and Alnilam are first magnitude stars (the lower the number, the brighter the star) while Mintak is a second magnitude star. After recognizing the belt it was easy to spot the other low-magnitude stars of Orion Constellation. They are Betelgeuse, Bellatrix, Rigel and Saiph. All have Arabic name except Bellatrix which was taken from Latin word that means the warrioress. Bellatrix is a first magnitude star so it was easy to see it. Next is Betelgeuse, the mighty one or the armpit in Arabic. This zero magnitude star is easy to recognize since its yellowish color is distinguishable from other member of Orion constellation. Coming next is Rigel the foot. It is a zero magnitude star which is 770 light-years distant from the earth but produces energy 50000 time than our sun which make it as the brightest star in Orion constellation. The last but not least is Saiph the sword. This star was dim since it was located near horizon which is polluted by houses light. Saiph is a second magnitude star like Mintaka.

Orion Constellation

Orion Constellation

After finding the great hunter Orion. It was quite easy to find other zero and first magnitude stars. Like Aldebaran (the follower) the brightest star in Taurus constellation. Since the other member of Taurus are third or fourth magnitude stars, I wasn”t able to see it clearly because of the light pollution from the neighborhood. Not far to the up right of Aldebaran, Pleiades (the seven sister) stars cluster looked quite dim but still visible. Sirius, the brightest of Canis Mayor and its companion Mirzam can also be spotted but the rest was unclear. The twins of Gemini constellation Pollux and Castor was very clear but at first I wasn”t sure because there was a bright and star-like object inside Castor-Pollux-Alhena triangle. After I confirmed it with Stellarium, I found out that it was Jupiter. It shone like a zero magnitude star with white and yellowish glitter color. I was able to spot the brightest in Canis Minor, Procyon  but wasn”t able to see Gomeisa, the other member of Canis Mayor since it is a third magnitude star.

Figure 1

Figure 1

The next thing I was curious about is the legendary star that will not move from its place although the earth is rotating. It is Polaris the north star. In order to find Polaris, it is easier for me to find the Big Dipper first. Big Dipper is a star formation part of Ursa Mayor constellation. It was quite hard tho find the Big Dipper because in winter around that time, Big Dipper is close to horizon which was obscured by trees and houses and I have to move places in order to locate it in the north sky, but once Big Dipper was spotted, I was able to locate Polaris the legendary north star.

Big Dipper and Polaris

Big Dipper and Polaris

By using Big Dipper and Polaris, enabled me to locate other constellation such as the Queen of the sky Cassiopeia. Capella the brightest start in Auriga can also be seen with the other member of pentagon-like Auriga constellation member. Unfortunately, the Queen Cassiopeia”s king, Cepheus was a little bit shy that night so I didn”t see maybe it was because the moon was too bright so it over-light Cepheus which mostly consist of  third magnitude stars. The only start I saw from Cepheus was the brightest Alderamin.

Well, That was my first time observing star and constellation. Although it was cold and windy but identifying star constellations like our ancestors did long time ago to help them navigating and farming was amazing.

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[Chord] Berjebraw – Forefathers

This song was written by Petra G Michael a.k.a Berjebraw. I got to listen to the song yesterday and decided to write the chord. The first time I heard this sing song. I felt like my soul was shaken. Here is the song and the chord

Tuning: Standard EADGBe
LEGEND
 E   C#    A    B   F#   G#   Eb
e|----0----0----0----0----0----0----0----|
B|----0----0----0----0----0----0----0----|
G|----9----6----2----4----4----4----9----|
D|----9----6----2----4----4----6----9----|
A|----7----4----0----2----4----6----6----|
E|------------------------2----0---------|
Intro : E
E                             Eb             E
Look at what the forefathers left for us
 Eb            E
Can you feel the spirit moving accordingly
 Eb
One thing I realize about this day
 C#               B
Oh, have we learned a thing or two
 A            B
From what our forefathers left
 E               C#
Have we learned, have we learned
 F#                                    E
Have we learned, have we learned from our forefathers
 E               C#
Have we changed, have we changed
 F#              G#             A
Have we learned, have we learned from the past
E                                   F#
Yesterday was that you learned
 A
Tomorrow is that for us to dream
 E
And today is that for us to live our life
 E                         F#
To change for the better, to change for the better
 A
To change for the better, to change for the better
 E
To change for the better
<p> E               C#
have we learned, have we learned
 F#                                    E
have we learned, have we learned from our forefathers
 E               C#
have we changed, have we changed
 F#              G#                 A
have we learned, have we learned, have we Learned
 F#      G#                     A
have we learneeeeeeeed, from our forefathers
 E
a thing or two
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Pie a Professor

Today, I saw a strange event in my school. Staffs in iSchool Syracuse University were raising money to be donated for United Way. What they did was providing a booth were people can throw pie to iSchool’s professors face. The price is $5 for student and $10 for faculty, but if you only have $3, they”ll take it anyway. I was also offered to throw pie on professor face, but I refused it is not because I didn’t have money, but I think that is not appropriate. I believe that in Asian”s culture especially Indonesian, in order to success, student must respect their teacher. Although, even if we (student) are angry to our professor when they gave/asked to much on our assignment or research and gave us a hard exam; all of them are for our own good (I used to be a teacher and also my father is a teacher too). Therefore, we shouldn’t hold any hatred to them. Moreover, throwing a pie in their face to let the hatred out is just not right. In my opinion , that”s like organizing prostitution for charity. Do you think that”s right? Why I compare it with prostitution? because they are the same in term of selling their honor. That”s just what came up in my mind where I saw it. Here are some videos that I took. I would like to hear your opinion as well.

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