Friday, June 16, 2006

Slingbox - A remote connection to your A/V equipment

Slingbox is a small hardware device that encodes an A/V input signal and serves it over the Internet. In this way you can have your favorite show with you wherever you go, without having to maintain a server PC at your home.

At first site the lack of an internal TV tuner may seem like a bad point, but this is actually the main design idea of this device: in allows controlling your existing A/V equipment. You may look at Slingbox as a remote connection to your A/V equipment. Instead of creating a complex and expensive device that may possible include TV tunner, PVR, etc., Sling Media created a simple yet effective device. Most people have already PVRs at home, so buying a second PVR doesn’t make sense from at least two reasons: first price and second you lose to ability to have all the recorded shows in one place.

To better understand the product just watch yourself this video, where a guy is checking his TiVO system, back home in US, while he is in a trip in Japan.

Note: A similar product (with a few cool additions) is coming from snappy MULTIMEDIA and is called HAVA. Although the client seems a little bit lacking the product is still very impressing.

Thursday, June 15, 2006

Recharge your phone in flight from the headphone jack

If you travel a lot then probably you’ll find very useful this device from InflightPower.com. The Inflight Power cable is designed to recharge existing low power devices such as cell phones or smart phones via a standard headphone jack found in most airline seats. The only requirement for your device is to be able to recharge from a USB connection.

Wednesday, June 14, 2006

PayPal as Skype wallet

It seems that Skype will become soon more than a simple VoIP client. At Financial Analyst conference, eBay revealed its plans to better integrate Skype with PayPal. Using Skype client you’ll be able to send money to anyone on your contact list. The other person will get the money in Skype client as well.

Tuesday, June 13, 2006

The hurricane season and the Floridian Law

I’m posting this not because is a VoIP news but because I live in Florida and the hurricane season just started. For the next six months every Floridian will turn on the TV or browse the NHC website just for finding out when the next hurricane will strike. Each day, while commuting, I’m listening a news radio station and they give advices and present stories about hurricane.

They give advices to install window shutters, to make water and food supplies and buy generators to comfortably pass those days after the hurricane (in case your city is hit). In contradiction with this, a friend of mine who renting a condo in a luxurious community told that he received precise instructions from his landlord about what to do in case of a hurricane hit. He is not allowed to install any generator or grill on the balcony or near the building and what is most important is not allowed to install window shutters. The only recommendation is to buy rental insurance.

While to not use a generator or grill may seem reasonable to not have the right to install shutters seems kind of odd. If for a business a disaster is only a matter of money, for a person, represents something more important, especially if the disaster affect something called home.

Is clear that a business is not interested in people but only in making more money (The Corporation movie is a must see) but what is not clear to me is why the state doesn’t protect more its citizens. While many things can be made, just two of them come in my mind right now (maybe influenced by what I heard from my friend):

Exactly like my friend’s community, many expensive rental communities down here in South Florida, usually have gated entries with security all day long. And they say this is for the protection of their tenants. While most of them have this almost none doesn’t offer window shutters that to me look also like tenant protection. Shouldn’t be the law more restrictive with the landlords? It is possible for the law, here in Florida, to impose landlords the simple thing to install window shutters to all residents in the moment a hurricane warning is issued? If you own the home then it’s up to you what you do during a hurricane but if you are a rental you don’t have too much choice. We live in a country while the law protects its citizens, and in case you didn’t know there are laws which protect also the renters from landlord’s abuses but there is no law to protect them in this situation.

While all media advice you to buy a carbon-monoxide detector if you buy a gasoline powered generator almost no generators manufacturer doesn’t include such a detector with the product. After each hurricane season the media presents cases where persons died because of invisible but deadly emanations of CO. Shouldn’t the law the one to impose manufacturers to include such basic detection device? If seems to much consider also the fact the law is the one that enforce producers to label each food product and list all the ingredients for the safety of the consumers. Then again why the law doesn’t see including such a device a safety method?

If you have more examples or just want to express your opining please leave a comment.

Sunday, June 11, 2006

VoIP Calls Recorder

Sniffing network traffic, VoIP Recorder from Duxoft is able to extract voice packets (H.323, SIP, MGCP) and store decoded audio data in WAV files. Due to sniffing technology used by the product you can record remote calls inside the local network no mater if the calls are between hardphones or softphones.

In a hub type network this kind of sniffing doesn’t raise any difficulties. But nowadays almost any local network uses switches instead of hubs. These devices provide an extra level of security and performance through their intelligent mechanism of distributing the data flow only to devices that participate into communication.

If the VoIP Recorder is used legally then you may activate Port spanning on your network switch (as Duxoft recommends). ‘Hackers’ out there may also benefit of this software by poisoning the switch through an ARP attack.

Although useful for some, this software may raise for others the issue of securing the VoIP communications. Without a proper VoIP encryption scheme anybody (I’m talking here about regular people not computer literate or hackers) on your local network may tap in your phone calls.

Saturday, June 10, 2006

C# Amusements

Is not really about VoIP or any other gadget but the subject may be still interesting to C# programmers out there. The following are a few C# tricky questions that you may also view them as programmer’s amusements.

1. Supposing you have a Windows Forms applications with 3 buttons, the event handlers for these buttons containing the following code, please tell what the result of pressing these buttons is.

private int m_p1;
private int m_p2;

public int p1
{
get { MessageBox.Show("get_p1"); return m_p1; }
set { m_p1 = value; }
}

public int p2
{
get { MessageBox.Show("get_p2"); return m_p2; }
set { m_p2 = value; }
}



private void button1_Click(object sender, System.EventArgs e)
{
this.p1 = 3;
this.p2 = 3;
}

private void button2_Click(object sender, System.EventArgs e)
{
this.m_p1 = this.m_p2 = 3;
}

private void button3_Click(object sender, System.EventArgs e)
{
this.p1 = this.p2 = 3;
}



2. Tell if the following code compiles and if runs what is the result. Please note that method DoSomething2 is private.

Test t = new Test();
t.DoSomething1();



public class Test
{
public void DoSomething1()
{
Test tst = new Test();
tst.DoSomething2();
}

private void DoSomething2()
{
MessageBox.Show("Hello");
}
}


3. Does the following code compiles and runs correctly?

private void DoSomething(int Count, string Name)
{
MessageBox.Show("1");
}

private void DoSomething(int Count, string[] Names)
{
MessageBox.Show("2");
}

private void button3_Click(object sender, System.EventArgs e)
{
DoSomething(3, null);
}


4. Tell is the following code is a valid C# snippet. If yes find out the result of running this code.

private void button1_Click(object sender, System.EventArgs e)
{
string @s1 = "STARLIMS";
string @s2 = "Corp.";

string u\u00731 = "Microsoft";
string u\u00732 = "Corp.";

MessageBox.Show(\u00731 + \u00732);
}


5. What’s the effect of executing the following code?

private void uiButton2_Click(object sender, System.EventArgs e)
{
int a = 2;
string b = "abc";

MessageBox.Show(a + b);
}


6. Is the following text a valid C# code? If yes what’s the meaning?

private void button1_Click(object sender, System.EventArgs e)
{
@class("abc");
}


… what about this one?

private void button1_Click(object sender, System.EventArgs e)
{
@return s;
}


Don’t hesitate to leave a comment with your answers to these questions.

Saturday, June 03, 2006

Secure your VoIP connection

From the creator of PGP, Philip Zimmermann, now comes new encryption software specially designed to secure your VoIP connection: Zfone for Windows (Mac OS X, Linux).

The software is designed to virtually work with any SIP compatible softphone such as eyeBeam, X-Lite, Express Talk, GizmoProject, etc. All you need to do before establishing a secure connection is to make sure Zfone is running and the softphone is using SIP port number 5060.

Unfortunately the ZRTP protocol used by Zfone is not yet known by PBXs or softphones and so you cannot make a secure call to a land line. Your contact must also be running Zfone on his side, and so the two instances of Zfone will create an encrypted channel through which the VoIP data will flow secured.