TCP/IP has four layers. (Application layer, Transport layer, Internet layer, and Network Interface layer).  

On the Application layer you will find Application protocols such as SMTP (for e-mail), FTP (for file transfer) and HTTP (for web browsing). Each kind of program talks to a different Application protocol, depending on the program purpose.

After processing the program request, the protocol on the Application layer will talk to another protocol from the Transport layer, usually TCP. This layer is in charge of getting data sent by the upper layer, dividing them into packets and sending them to the layer below, Internet. Also, during data reception, this layer is in charge of putting the packets received from the network in order (because they can be received out-of-order) and also checking if the contents of the packets are intact.

On the Internet layer we have the IP (Internet Protocol), which gets the packets received from the Transport layer and adds virtual address information, i.e. adds the address of the computer that is sending data and the address of the computer that will receive this data. These virtual addresses are called IP addresses. Then the packet is sent to the lower layer, Network Interface. On this layer packets are called datagrams.

The Network Interface will get the packets sent by the Internet layer and send them over the network (or receive them from the network, if the computer is receiving data). What is inside this layer will depend on the type of network your computer is using. Nowadays almost all computers use a type of network called Ethernet (which is available in several different speed grades; wireless networks are also Ethernet networks) and thus you should find inside the Network Interface layer the Ethernet layers, which are Logic Link Control (LLC), Media Access Control (MAC) and Physical, listed from up to bottom. Packets transmitted over the network are called frames.

A router is a device in computer netwoeking that forwards data packets to their destinations, based on their addresses. The way it works is somewhat like switching, but a router is different from a swtich, for its simply a device to connect machines to form a LAN.

A network switch is a small hardware device that joins multiple computers together within one local area noetwork. (LAN). Network switches operate at the second layer, of the OSI model.

A network hub is a device providing the interconnection between networked devices. It is called a hub because the network wiring can be sketched like a spoked wheel with the hub at the center. A Network Hub is used with 10-Base T and 100-Base T EtherNet wiring. Hubs differ in the number of ports they have and in large networks multiple hubs can be bridged together.

A MAC address is a unique identifier assigned to most network adapters by the manufacturer for identification, and used i nthe Media Access Control protocol sub-layer. If assigned by the manufacturer, a MAC address usually encodes the manufacturer’s registered identification number.

Computer specs now have quad core processors and our ram is very commonly 4 gb and sometimes 8 gb.  Our GPU’s are nvidia 8800-9800 gt and gts, and the gtx 260 and 280. We can now also have a hard drive of 2 terabytes.

Some phones back in 2000 were the Motorola Talkabout T8160. These phones were very basic with low resolution. They were usually flip phones, with large keys. Nowadays we have phones such as the iPhone, and blackberry, or as some would like to call it the “Crackberry”.

The phones nowadays such as the iPhone do not even use buttons, since it is touch screen. The screens are now also in very high resolution. What probably is the biggest breakthrough, is that you can now surf the web on your phones. It is amazing how big of a gab humanity has further developed the technology of cell phones in such a short time. In about 10 years from now, we may be thinking the exact same thing.

If we were to compare our gaming systems from 2000 to now, it would have to be a major change. The systems often played 10 years ago were the N64 and playstation.

Today we play such systems as the xbox360 and PS3. If you really think about it, it is amazing how in only 10 years there has been wireless controlers, amazing graphics in HD, and most of all online gaming. The games nowadays not only have better graphics, but we can go online and play other humans.

In 2000 digital cameras were starting to become popular. It was the start of many technologic opportunities. The cameras had around 2.0 megapixels, with a very small preview screen, and not very good resolution. The optical zoom was around 3x optical,  and the image sizes were, 1632 x 1224, 1024 x 768, 640 x 480.

Today, cameras have  10 to 15 megapixels with great resolution. The zoom depends on the lens you have. I feel as though cameras have not changed as significantly as other things, such as the gaming industry. However it still is a big change, and will continue to do so.

Moore’s law describes a long-term trend in the history of computing hardware, in which the number of transistors that can be placed inexpensively on an integrated circuit has doubled approximately every two years. The term “Moore’s law” was coined around 1970 by the Caltech professor, VLSI pioneer, and entrepreneur Carver Mead.

Sixty per cent of Xbox 360s have kicked the red-ringed bucket, compared to 16 per cent of PS3s and just 6 per cent of Wiis, according to our survey on the reliability of games consoles in the UK.

I think that this is a huge concern. Many buyers who purchase their xbox 360s expect to get the full value of their moneys worth, but 60% of buyers will get red ring. Microsoft should fix this problem already, if Ps3 and wii can handle these problems a lot better, then the xbox 360 should surely be able to also. However, it doesnt, and for the moment, xbox 360 owners will just have to pray that they dont get red ring.

Facebook: A tool for cops and robbers

In Venezuela criminals use Facebook to research targets. Cops use it too — but not always for scrupulous purposes. It has been revealed that police find ways to arrest criminals from information they comply using Facebook.

I think that this way of criminals tracking targets, and cops using it to get dirt on criminals is somewhat wrong. People use facebook for a mild sense of satisfaction, only to get themsevles stalked, and later in danger because of the information that they, or their friends post. This shows that you should be concerened about your privacy on facebook, and be more carefully for what you post.

Pros
Fast
Very good image quality

Cons
Very high playback requirements
Majority of installed base not capable of viewing MPEG
Licensing fees (typically US $0.04 – $0.40 per unit) are required to distribute MPEG-2 video. There may also be fees for MPEG-1; there is some uncertainty regarding this. Mpeg-2 DVD

Pros
Excellent image quality

Cons
Very few people are currently capable of viewing MPEG-2
Licensing fees (typically US $0.04 – $0.40 per unit) are required to distribute MPEG-2 video.
Does not have as much space as blu-ray Mpeg-2 Blu-ray

Pros
Excellent image quality
more space than dvd

Cons
Very few people are currently capable of viewing MPEG-2
Licensing fees (typically US $0.04 – $0.40 per unit) are required to distribute MPEG-2 video. ADOBE FLASH VIDEO

Pros
The Flash player is installed on a higher percentage of end user computers than any other video format. Although not all end users have the latest version installed (so they may not support the latest Flash video codec), Flash still enjoys the best overall support.
Flash files look the same and work equally well on PCs, Macs, Linux, etc. Flash files are completely consistent, so once you test and implement your Flash video, you can be confident that it will function the same way for all end users (apart from obvious variables such as connection speed). It’s hard to overstate the importance of this for web designers.
Flash provides unparalleled options when it comes to interactive content and other advanced features. Even Quicktime pales in comparison.

Cons
Flash video does not have the same depth of history as the other major formats and it has experienced some “growing pains” in the last few years. Between versions 5 and 8, Flash video went through two major changes which required a lot of upgrade work for producers.
Although it’s possible to publish your first Flash video in less than an hour with no previous experience, you can do the same with other formats even faster. For example, you can embed a Windows Media file in a few minutes by copying and pasting some HTML. Even the simplest Flash installation is a little more complex.
It runs on FLV, which is the Flash video file format. There’s nothing wrong with the format itself but because it’s not a common distribution format like Windows Media or Quicktime, you may find that you often have to convert files from other formats to FLV. This takes time and any extra conversions between compressed formats will reduce quality. H.264

Pros

H.264 offers dramatically lower bit rates and better picture quality than MPEG-2, MPEG-4 or H.263+
It is 2X times more efficient than MPEG-4. and file size is 3X times smaller than comparable MPEG-2 Codecs
It is easy to integrate and covers wide range of picture format. Hence used in large application segment.
H.264 delivers incredible video quality at data rates one-fourth to one-half the size of previous video formats

Cons
H.264 requires longer encoding time
It is certainly not constricted and low-bandwidth friendly
More Hardware overhead is also one of the limiting factor
Licensing agreements are complicated.
]]> http://barlescu.wordpress.com/2009/11/16/codec-comparison-html-table/feed/ 0 barlescu http://barlescu.wordpress.com/2009/11/16/codec-comparison/ http://barlescu.wordpress.com/2009/11/16/codec-comparison/#comments Mon, 16 Nov 2009 01:47:12 +0000 barlescu http://barlescu.wordpress.com/?p=123 ]]> Mpeg1

Pros

-Fast

-Very good image quality

Cons

• Very high playback requirements
• Majority of installed base not capable of viewing MPEG
• Licensing fees (typically US $0.04 – $0.40 per unit) are required to distribute MPEG-2 video. There may also be fees for MPEG-1; there is some uncertainty regarding this.

Mpeg-2 DVD

Pros

• Excellent image quality

Cons

• Very few people are currently capable of viewing MPEG-2
• Licensing fees (typically US $0.04 – $0.40 per unit) are required to distribute MPEG-2 video.
• Does not have as much space as blu-ray

Mpeg-2 Blu-ray

Pros

• Excellent image quality
• more space than dvd

Cons

• Very few people are currently capable of viewing MPEG-2
• Licensing fees (typically US $0.04 – $0.40 per unit) are required to distribute MPEG-2 video.

ADOBE FLASH VIDEO

PROS

• The Flash player is installed on a higher percentage of end user computers than any other video format. Although not all end users have the latest version installed (so they may not support the latest Flash video codec), Flash still enjoys the best overall support.
• Flash files look the same and work equally well on PCs, Macs, Linux, etc. Flash files are completely consistent, so once you test and implement your Flash video, you can be confident that it will function the same way for all end users (apart from obvious variables such as connection speed). It’s hard to overstate the importance of this for web designers.
• Flash provides unparalleled options when it comes to interactive content and other advanced features. Even Quicktime pales in comparison.

CONS

• Flash video does not have the same depth of history as the other major formats and it has experienced some “growing pains” in the last few years. Between versions 5 and 8, Flash video went through two major changes which required a lot of upgrade work for producers.
• Although it’s possible to publish your first Flash video in less than an hour with no previous experience, you can do the same with other formats even faster. For example, you can embed a Windows Media file in a few minutes by copying and pasting some HTML. Even the simplest Flash installation is a little more complex.
• It runs on FLV, which is the Flash video file format. There’s nothing wrong with the format itself but because it’s not a common distribution format like Windows Media or Quicktime, you may find that you often have to convert files from other formats to FLV. This takes time and any extra conversions between compressed formats will reduce quality.

H.264

Pros

• H.264 offers dramatically lower bit rates and better picture quality than MPEG-2, MPEG-4 or H.263+
• It is 2X times more efficient than MPEG-4. and file size is 3X times smaller than comparable MPEG-2 Codecs
• It is easy to integrate and covers wide range of picture format. Hence used in large application segment.
• H.264 delivers incredible video quality at data rates one-fourth to one-half the size of previous video formats

Cons

• H.264 requires longer encoding time
• It is certainly not constricted and low-bandwidth friendly
• More Hardware overhead is also one of the limiting factor
• Licensing agreements are complicated.

Google chrome is googles new operating system. Google Chrome OS is an open source, lightweight operating system that will initially be targeted at netbooks. Speed, simplicity and security are the key aspects of Google Chrome OS, and hopefully users will appreciate it. The user interface is minimal to stay out of your way, and most of the user experience takes place on the web. Google chrome seems very promising.

2. Someone at Microsoft is Taking LSD… [PIC] view!

3. Another Reason why Time Warner Sucks

4. Windows 7 Release Candidate 1′s Best Surprise New Features

5. Ubuntu 9.04 “Jaunty Jackalope” officially released

My favourite were the first 2. For it really amazed me how you can create kool pictures with technology. It makes me think that in the future pictures will not be drawn by and, but by computers.