This question was cobbled together from several common e-mails this week.
Hey, Inetdaemon, Doesn’t bandwidth solve all network problems with [Skype, Facetime, Vonage, NetFlix, Hulu, YouTube, World of Warcraft (WoW)...], and push my frame rates through the roof in [choose any FPS/MMORPG]?
Answer: Not so!
Engineers use a measurement called “latency” to measure delay between endpoints in communications systems, including the Internet. High latency is bad, low latency is good. High latency indicates a problem between endpoints. This could be you and a friend across Skype, Facetime, Vonage or anything else. Problems with ‘delay’ are the real causes of ‘slowness’ and communications problems. More bandwidth will only solve are issues of congestion and over-subscription and only if you can add more bandwidth along the entire path from end-to-end. It can’t do anything about the actual delay from the communications system and the infrastructure supporting it or from the server. Moreover, if the “internet pipe” at the far end serving the person or site you’re trying to reach is full, or the equipment that pipe is connected to are busy, there’s no benefit to upgrading your service to higher bandwidth. Given the nature of the Internet, everyone else would also have to upgrade thier Internet connection to make your services faster.
Why can’t I buy a basic 4:3 1600×1200 LCD monitor any more for less than $380?
A 1080 monitor is “missing” 120 pixels of vertical resolution. In practical terms, this means you spend a LOT more time scrolling up and down when you browse the web, write a Microsoft Word document, edit your latest eBook, work on updating your website.
When it comes to computers, I’m a power user. Lots of applications running, Internet browsers, file transfer applications, e-mail, office applications (Word, PowerPoint and Excel), graphics and website development software, even video conferencing from time to time, all at the same time. It takes not only a lot of CPU and RAM to run all of this, but it takes a lot of desktop real-estate too, which is why I need high-resolution monitors. The rise of High Definition television (HD or 1080p) and mobile devices has brought about an odd situation. Six years ago, you could get a 1600×1200 LCD/LED monitor for around $189. I bought two Samsung monitors at that price. One of them failed recently, and I went shopping for a new monitor with the same resolution, only to find that I had to choose between medical-industry-grade monitors at $1200+, new monitors at $450+ (if I could find them), refurbished monitors for around $200, or settle for a 1980×1080 monitor.
I was flabbergasted that you just can’t buy a new, standard 1600×1200 monitor these days for under $300.
After some research, I discovered that the people that make monitors aren’t interested in making PC monitors any more. They can take the same materials and produce an HD television at three times the price. A basic 27-inch 1920×1080 LCD monitor will run you $109 US. A 27-inch 1920×1080 HD-TV will run you $349 US. Manufacturers add a tuner component, but otherwise, the HD-TV is the same materials, components, screen-size and electronics. Because it’s an HDTV, you’re willing to pay more and so you do, and the manufacturers realized that at a 250% markup, HD-TV’s are more profitable, so they retooled their factories to turn out 1920×1080 screens for HD-TV’s. Even better, they can carve up what could have been a $109 27-inch screen into a dozen iPhones, charge $100 for each iPhone screen, and make at least 600% markup with the same materials and production costs. Thus, today’s monitor manufacturers see PC monitors as “unprofitable” by comparison to HD-TV’s, mobile phones and tables, so they refuse to put anything more into a PC monitor than is required to get a consumer to buy it. Since they converted their factories for HD TV’s, they can only crank out 1080 PC monitors now. Setting up a production line to turn out a 1600×1200 monitor may be possible, but they see making a smaller profit as a financial loss. Since consumers are unaware that 1600×1200 used to be the standard monitor size and didn’t continue to demand them, the manufacturers have gotten away with stealing away the 120 pixel-rows at… Continue reading
Web Technologies by Jeffery Jackson says HTTP stands for Hypertext Transport Protocol, but your site says it is HyperText Transfer Protocol. Which is it?
We covered the OSI Model in CCNA Lesson 5, now we move on to the TCP/IP Model which you will also need to know for the CCNA exam. Since internetworking is based on the TCP/IP protocol suite, the TCP/IP model is a bit more important than the OSI model on the CCNA exam.
While the ISO folks were meeting in committees to develop the OSI Reference Model, the rest of the world got busy making networks actually work and the TCP/IP suite of protocols is the result. The TCP/IP model of networking describes how the TCP/IP protocol suite functions and operates. Simpler than the OSI Reference Model, the TCP/IP model describes the most common stack of network protocols in use today. This network model goes by several names: the DARPA Model, the Department of Defense (DoD) Model, and today we just call it the TCP/IP Model.
There is a full tutorial on the TCP/IP Model here at InetDaemon.com.
There are two basic network models, the OSI Model and the TCP/IP Model. Both outline the basic functions of how networks work and are each a standard in their own right. Understanding the OSI Reference Model is a requirement for passing any exam on networking whether it is the CCNA, CCNP, Network+ or any Juniper exam.
Memorize the OSI Reference Model. Now. You’ll use it over and over again and none of the information we cover from here on will make any sense if you don’t. Networks were built one layer at a time over a period of time. First physical communication was made possible, then logical addresses were used to allow you to move computers around on a network. Next, the ability to route packets from one network to another was worked out, then ways to guarantee delivery of large volumes of data and finally ways to boot up and to manage the network, provide names humans can remember, and finally to serve up stored data as web pages.