Tuesday, July 31, 2007

PSTN and SIP open standard

I have tried to convince Anirban to continue writing about this, he is too busy. I am not that busy, but I start to feel a little hard in explain all these. I will try my best. Before we describe the complicated system, we still have some basic ideas to clarify. This time, it is the difference between the PSTN and SIP phone.

PSTN (public switched telephone network) is the world's collection of interconnected voice-oriented public telephone networks, both commercial and government-owned. The feature of this phone comparing to VoIP phone is the inefficiency of the use of wires. When a phone call is connected, the wire transfer of the voice between two users at either ends will occupy the entire wire connecting them. On the contrary, VoIP involves sending voice information in digital form in discrete packets which allows lots of packets to share parts of their routes along the same wire.

SIP is an open standard for VoIP technology, which is like SMTP for email communication. We all know about SKYPE, but in fact SKYPE built their system on a proprietary protocol instead of SIP open standard. As a result, SKYPE can only work within its individual client. And SIP based network can be connected with users out of the box, since most of the hardware development are following the open standard, and they are able to exchange in the future. This is how the SIP based VoIP network can also be connected with the PSTN network. (Skype can also do this at the moment, but it involves a fee for the calls. For SIP based phones, you can easily find free services.)

So, what the VoIP technology does, is to let the internet carrying voice signals, and also possible to connect to the existing PSTN network. Every PSTN has a number, so VoIP also needs a number to communicate with it. If you want others to reach you, you should have a number that everyone can dial using their home regular PSTN phone. Where and why can you get a free PSTN number, let's keep it for the next time.

Monday, July 23, 2007

Public Library

There is a rather new public library in the center of the downtown. Mr. and Mrs. Awaara went to check it once, and found there were lots of DVD for check out over there. However, the public library membership is not free. An individual membership cost around 36 euro per year.

We were quite surprised at the beginning, since city's public library is always free in the US. You just need to show your valid ID, with a proof that you live in this neighborhood, something like your last month electricity bill. There was a limit on how many books you can check out every time, which is more than you could handle at one time. I remember the Foxpoint library we used to go to, mainly for checking out movies to watch on our little laptop. It was only three blocks from where we live. We mostly order the movies online. The library will send us email to inform that our order is ready for pick up. What you are checking out is actually from a pool of all Providence public libraries. They will bring your order to the closest library you would like to go pick up. Also, there are quite a lot of information is online. In terms of this, Boston public library is much better comparing to the Providence ones. I remember I once used Yiling's membership to download a movie from BPP.

Back to the Delft library, we finally decided to go to get a memebership just for checking out DVDs, since most of the books were in dutch. We feel that we need to have this membership to spend the long winter in Europe. Last Friday, we went there after Mr. Awaara left his office. It opens till 9pm on Fridays. You know what, they are giving three months' free membership! Let's have one. I signed up and we were excited running uptaris, starting looking through all DVDs. Soon, we collected five, and I went to check out.

The system of catologing of DVD is interesting. They made the cover of DVD case in identical plastic clip, listed alphabatically. You can collect your interested movies and go to the circulation desk. Assistants there will help you find the real DVDs in the safe: selves made out of steel. They are well indexed, and it doesn't take long to find out.

It is smooth in finding out all those five DVDs, and they scanned my library card, and gave me all those movies. I was quite satisfied and grabbed all of them and ready to leave. As soon as I turned, i was called. 'Hi, you need to pay.' WHAT???

So the policy is, every DVD you can check out for a week, and pay 2.5 euro for each copy. Isn't this the public library? Yes, it is. But we don't have enough funding so we have to charge a fee for DVDs.

WOW, we are further and further away from all the free stuffs that we enjoyed in US. Here it seems that nothing is free. We have taken for granted many things in the US. In US, you get tons of emails to seduce you to apply for a credit card with all kinds of offers. Here, you have to pay a management fee if you want to use a credit card. You also need to pay annual fee for a bank account. Banks are so rich place, but they still wouldn't let the business sector of the bank subsidize the personal banking as what happens in the US. Now our banking account costs around 40 euro per year. They augue the reason they are doing this is to prevent people opening multiple accounts but made them stay idle. It doesn't sound reasonable to me. At least my previous account in the US will be closed if there are no activities for certain days.

Friday, July 13, 2007

Shopping cart collection

Let's see how much I can write in half an hour time. Being away from the internet is like the life being cut off from the outside world. Mr. Awaara called the service provider and was told that it needs 15 working days to get the connection. 15 days!!! can you believe it? I am a little shocked. What is there they need to do for 15 days? In Providence, it is the same day i remember. Why does it need so many days?
One reason was convincing about the service sector less efficient and higher cost is about the Dutch language. It is a language spoken by 16 million people in the netherlands and some in Belgium. Although almost all dutch can speak English, they are proud of their own language, and they want immigrants in their country to learn to speak dutch. As a result not like US, all customer service lines can be outsourced to Indian. Dutch have to do it by their own people. This might affect their lower ability to hire more people because of high cost of labor in this country.
As we are here in this country for a while, we are discovering things that are different from US. It is hard to see which one is better, maybe you can judge based on what I am telling.

One interesting thing is about the supermarket shopping cart collection. People living in US must have the experience of going to the market with a shopping cart. Bringing everything you bought in the store with the cart and dump them in front of your car trunk. And then? If your car was happening to park close to a cart collecting point, you might push it there. If there is no collecting point or it is too far away, you will see carts are literally scattered around the huge parking lot. Then, a working position is also created: a shop assistant specifically in charge of collecting all those carts.
Here in the netherlands, things are different. You don't have to pay for using a shopping cart over a shopping basket, but you are bound with the responsibility of return the cart to the original place by paying a deposit for using it. The deposit was a coin, can be either 50c, 1 euro, or two euros coins. All carts are parked with a chain locking them together. Inserting a coin in a slot on the chain can allow you to free one of the shopping cart. After returing it back and locking it back to the chain, you are able to get your coin back. It is a simple idea, but it does make a lot of sense. It saves a labor in the shop to work on it. Stores here are usually more crowded shelfed, this way also discourage the use of cart and encourage the use of basket. The trick is only the design of the chain.

Monday, July 9, 2007

Hugo de Grootstraat (Grand Hugo street)

Finally, five weeks after coming to Delft, we moved to the new apartment where we signed a one year contract with. It is a nice, much bigger, and a little luxury apartment comparing to students living conditions... Well, we decided that we don't have to live like students any more.
Our landlord is a couple from Surinam and their kids have both grown up and left for their work elsewhere in the Netherlands. The husband is an active political party elected leader, in the labor party. We saw his information in a city hall published booklet, and it shows his address. That way, we already saw his information and realized he was our landloard long before we moved in.

It is the summer time and the library clost at 5:00pm. I just started writing and it seems it is the time to wrap up. Our internet at home is not working yet. We are waiting to use the University provided free internet service, so it takes a little longer to set up everything.

Thursday, July 5, 2007


VOIP (Voice Over Internet Protocol) is the service including any sound communication over the internet. What we have been mostly familiar with are SKYPE, MSN messenger, Yahoo messenger, Google talk. All these services have allowed us to talk over the internet, basically a communication from one computer to another computer. All of these are different software clients, which we might have to install a small program on our computer to be able to talk. What these softwares do, is basically converting your voice to digital signals and sending to the internet, at the same time, converting the received signals to voice in your speaker.

The VOIP ATA (analog telephone adapter) phone I am talking about, uses a hardware - the VOIP router. What the router does, is exactly the same as what the software chatting clients do: converting signals to support the internet talking. When using the software, we know we have to turn on the computer and lauch the program. However this hardware router, we can just keep it connected with the internet. If there is no power cut or network problems, the hardware will be all the time ready to send or receive signals to enable a phone call. Here is a picture of our router:
In US, i think most people have heard about Vonage, the internet phone. This company has spent a lot of money on advertisement. What it has done, is some more development based on this kind of hardware router. It also made the 911 calls possible, and providing you a local number. The final service is more than 20 dollars per months i believe. They lock the hardware in their own service. So when you look for a voip router, remember to buy one that is not locked to any internet phone services. You want to have an open router that you have the full freedom to configure.

With this critical hardware, the internet connection, and the regular telephones, till now we have collected all necessary hardwares to set up the VOIP ATA for phone calls. However, the critical part is still ahead, the configuration of the ATA is the key.

VOIP ATA phone - good and bad

It has been more than one year since we set up our home phone totally relying on the VOIP (Voice Over Internet Protocol) ATA phone. It has been working fine for us, and we have convinced my sistere to change their home phone also. Although we are not the only one who is using this, i still feel there are few people are aware of this option. I didn't do any research myself. Mr. Awaara should take all the credits for this work, and I just try to describe it here to the public.

Our phone is just like any ordinary home phone at home. The phone number is a little tricky. We were using a free PSTN number from the Washington state. The good part of this number is its ability to carry anywhere you go. Now we are in the Netherlands, friends in the US can still reach us by calling an US number. Doesn't this sound great? Meanwhile, we also have a UK number, a Netherlands number. Either of these number is called, our phone will ring. How is it?

The most important, it is almost free. The main investment was a VOIP router that we spent 90 dollars on it. Other than this, the past one year phone bill including all the international calls we made often, is less than 10 dollars. This is great, right? OK, let me summarize the plus and minus of this phone first:

1. Same number reached anywhere in the world as long as an internet connection is available;
2. Very low cost. For those who don't need an internet connection at home, this might involve a cost transfer from paying for a phone connection to an internet connection. I am sure you will get a lot more using the internet connection.
3. Flexible phone features: if it is a PSTN phone, you might have to pay for the extra service like caller ID, or call forwarding, all these are just an option you can select in VOIP ATA phone.

1. You might have to do quite a lot of research to understand the system and set it up and maitain it. But there is also lots of fun in this process.
2. There is no 911 service for this phone. Since 911 service need to locate the phone address immediately, from the IP address it is still hard to find a physical address. Regular phones pay every month extra for 911 service. Since this one doesn't pay any bill, you don't get this service either. As a result, a cell phone at home is still necessary to work as a backup.

If all these have convinced you, you can keep reading the rest of the same label posts, and start investing your research time on it.

Wednesday, July 4, 2007

Lock-out experiences at Delft

I still remember the dream of growing up when I was little was to become some kind of '家', either a scientist, a writer, or an artist. It seemed that anything with that word proved that you became an specialist in that area, and you were great. As getting older, this dream stays away from me further and further away. I don't know whether it is because i slowly realized that my potential is limited, or there is another kind of quiet and peaceful life becomes more apealling to me. It is interesting to see that there are little tiny things become touching and unforgettable to me. In any kind of situation, i start to learn to enjoy the process of my life.

It is amusing to realize at this time, being in Delft for one month, having lived in two places, we have already had experiences of locking ourselves out of our apartment once in each places. The first time is when we lived in the Orange street, when we went out for a walk after dinner, we found out that neither of us had a key. We went to the back of the apartment, hoping that we could somehow getting inside the backyard. We didn't lock the door to the backyard from inside, so it shouldn't be a problem after that.
Mr. Awaara tried hard, but it seems hard to climb over. A guy biked passing us, and i stopped him asking for help. He thought for a second and asked us to wait. Guess what? he went to take a ladder for us! The other side of the wall, there was another ladder from the landlord. Mr. Awaara easily went inside and got our key. That is a nice guy. We later wondered a little bit that how could he believe that we were not thieves but tenants living there? Maybe we were just looking nice people :-)

The second experience was not that easy, and it could be seen as an adventure! It happened last Thursday night (Good that it is not Friday, you will know why) .
Mr. Awaara picked up a cellphone on the way home from the office. Later the phone was called, and they were informed that it is lost and with us. The owner's son said he would come to pick it up. Later he called again saying he couldn't come right away because his office called him, so we decided to go to the grocery first. On the way back from the grocery, someone again called, and telling us that he was waiting outside of our building. We asked him to wait for twn minutes. Mr. Awaara went home to return the phone. I was hanging around in the campus, using the truphone to call my Mom since the wireless signal is better there.

A few minutes after I was talking with my sister on phone,
Mr. Awaara came back, and I was not ready to hang up the phone. He waited for a few minutes, and started to talking to me. O O , I understood, he tried to tell me the key was locked inside! I soon hung up the phone with Yiling and i know this time it would be a bigger problem. We knew the landlady this time only have this only one key, and we are living here only through an informal arrangement. We have to ask her for help. She has to go to the housing office to get the key. It was already 9:30pm that time. I only have her number in my email, and good that we could go to Mr. Awaara's office. He has the office key in his pocket.

Using his office phone, we called our host. She said she didn't have similar experience after living there. She gave us another number to call to find out what will be the procedure. Then another call told us, there is no way to get it tonight only if you have to pay 50 euro. During office hours it is possible to get it. This is the reason that we were lucky to be in Thursday. The landlady sounds reluctant to help also because it is quite late. She suggested we went to her place to stay for a night. We were both not liking to bother others, so we said we could stay in the office for a night. In US, we both remember that Shane who later become a lecturer in the ENVD lived in the office for half a year. So a night is not a problem for us. There was another suggestion that we could try to hit the door, or using some card to open the door.
Mr. Awaara decided to go back and try. I stay in case the building locks after 10:30pm and I could still open the door for him. We once left after 10:30 pm and the building alarm sounded, which is quite annoying. We saw the security car passed by, but they didn't know it was because of us. ok, at this moment it was 10 to 10pm.

It was 10:15pm, I called
Mr. Awaara. He didn't succeed, so i asked him to come back.
Around 10:25pm, his key is useless any more to open the building door and he rung the office phone from downstairs, so i ran out of his office to open the door for him. When I came to the ground floor, i heard the screaming sound of the alarm. We both ran back to the third floor his office. It was scary. What did we do wrong? maybe the door shouldn't open after 10:00pm?

We sat quietly in the office. Later we felt the alarm went off.
Mr. Awaara went to the corridor to check. The second time he went back, telling me the alarm is on again! It seemed that every move of us would trigger the alarm. So we decided to face the police, it seems there is no way that we can safely stayed in the office without going to the toilet, or anywhere out of his office.

Around ten minutes later, three security person came. One short black lady, two guys one senior and the other younger. The lady started by saying, the building is closed at 10, and now it is 11 already, you can't not stay here any more. You have triggered the alarm twice. Please give me your ID... So
Mr. Awaara handed his ID, and we were driven out of the building.

That time it was around 11:30pm. We had no ID with us, our room was locked. Those security people knew that we would be homeless if they drove us out of the office but they still did it. We couldn't go to a hotel, since we had no ID, and not even knowing where will the hotel be. There is only the last chance, our host. Good that she is a night person. We called her at the rate of 25 eurocents per minute with our prepaid T-mobile phone. She told us where she lived, and we walked there. There is one room empty tonight in their 14 people shared apartment, and she talked with the person who lived there and she agreed to let us stay there. It is good that it was not too far away.

That is what i have said, you never know what your life will bring you. Just enjoy every moment of it. This adventure showed us a totally new way of living at Delft. It is like the student dorm, 14 rooms with a shared kitchen and shared toilet. They seemed to be all college kids, mostly white guys. We saw three girls when we entered. All guys were in the living room watching TV with beer, talking and laughing. They are really handsome boys! I like to see dutch boys in their early twenties. Other than this, the dorm was in a mess: bags and piles of stuff were everywhere in the corridor. I was thirsty and asked for water. Dishes were piling up high in the sink. I got a cup which looked quite dirty and i have to wash it.

Hecker, the German girl who is an exchange student showed us the room she just emptied, and also provided us a sleeping bag. We got a single bed for this night, with matress but no bed sheet. We lied down with all the clothes on. Every where is the smell of cigerates. Downstairs the music was loud until very late, and there were mosquitoes making noise near my head... anyway, this is still better than staying outside, it was only in low 50s.

The next morning,
Mr. Awaara went up and left for the office at 8:00am. I went to knock our host's door at 9am, the housing office should be open. She got up and did her normal cleaning up, had her breakfast. During the time she got ready, I took some pictures of the apartment. Mr. Awaara told me that there was a very sexy poster in the men's toilet, but I missed it.

Then our host borrowed the bike from the German girl and went to the housing office. I walked back home and waited for her. It was not long waiting, and I soon went inside the apartment. She took the key and left. I felt i was all over smelly and took a shower and changed all clothes.
Mr. Awaara stayed smelly until later that day. Now both of us remember, when we try to close the door, we need to make sure that the key is in our pockets. It is really a big adventure, and I am quite satisfied with the experience we had. I will later post picture stored in our cellphone camera.