Posts Tagged ‘data flow’
June 22nd, 2009 | 
Author: This is another CCNA exam preparation tutorial about the Transport Layer of the TCP/IP suite. Understanding the purpose and functionality of the Transport Layer (Layer 4 in the OSI model) is fundamental for understanding how data is transmitted in network environments.
The Transport Layer resides between Application and Network layers and has the critical role of providing communication services directly to the application processes running on different hosts. As message data arrives from an Application Layer to the Transport Layer, the latter places a header on the data in order to identify from which application the data was received. This Transport Layer header contains a Source Port Number and a Destination Port Number. The Port Numbers identify the application from which the data was received or is destined to. Read more on port numbers later in this article.
Another role of the Transport Layer is to provide reliable communication and flow control. The two most well known protocols that work in the Transport Layer are TCP and UDP. TCP is a connection-oriented reliable protocol that uses flow control mechanisms and acknowledged data delivery to offer reliable communication. UDP on the other hand is a connectionless and unacknowledged protocol. Now, the Network Layer (IP layer 3), which is below the Transport Layer and is responsible to route packets between hosts, does not offer reliability for data delivery. That is why we use TCP on top of IP (hence the TCP/IP suite) in order to provide reliable and error free data flow communication.
As we mentioned above, the Transport Layer uses Port Numbers to differentiate between various applications that might need communication services. You should be ready to get questions in the CCNA exam regarding port numbers and their association with different applications. You should know that port numbers below 1024 are reserved for several well-known applications. Some examples are shown below:
– FTP (TCP Port 21)
– Telnet (TCP port 23)
– SMTP email (TCP port 25)
– POP3 email (TCP port 110)
– DNS (TCP or UDP port 53)
– TFTP (UDP port 69)
– SNMP (UDP port 161)
– RIP (UDP port 520)
Harris Andrea is a Cisco Certified Professional (CCNA, CCNP, CCSP) with more than 10 years experience in the networking field.
Harris recommends the following CCNA Video Training package to help pass your CCNA exam Guaranteed.
A Computer Based Training (CCNA CBT) is the best option for studying for your certification.
Article Source: CCNA Exam Prep. Understanding the Transport Layer and Port Numbers Tutorial
There are lots of people building websites these days, but few are doing it well. Why? Website design is evolving at lightning speed. There are over 100,000 websites PER DAY being added to the internet. Someone is always innovating, and web companies have to constantly adapt their designs to incorporate these new methods. Search engine optimization, blogs, shopping carts, internet merchant accounts, pay per click advertising, designing in layers, flash animation, stream video and audio, RSS feeds, data warehousing, and that’s just for today! NeoNexus will help you through this maze of terms and get you to the bottom line…turning your website into a money making machine and not just sitting in cyberspace like a digital business card.
Interested in a flash animation for your website? Let our flash experts add a little extra jazz to your website, or corporate presentation. Go beyond Powerpoint and experience presentations that actually keep your audience awake.
It takes technical, artistic, and marketing knowledge to build a website that generates you revenue. Experience “art techo” from NeoNexus, the fusion of these skills into superior website design.
PDA devices are on the verge of reaching critical mass. Not only has hardware innovation accelerated, but the fusion of cell phone and PDA into the SmartPhone is finally making doing real computer work on your handheld device a reality.
NeoNexus offers several PDA environmental applications that work either with our web systems or stand alone. Eliminate that critical initial field step of putting information on paper field logs and accelerate your data flow to near real time. In addition, our PDA application design has segregated our application and data layers, giving us the ability to adapt our existing data capture software to different markets with little effort on our part. If you are a realtor, property assessor, contractor, auditor, salesman, or anyone else that collects data from many locations outside of your home office, you can benefit from our PDA data capture technology.
NeoNexus is your information technology company devoted to leading (and bleeding) edge internet solutions. NeoNexus has a strong foundation in web based environmental data management. Building on that expertise, NeoNexus is delivering data integration services, geographical information systems, and web site design and hosting for clients across all business markets.
Article Source: Why? Website design is evolving at lightning speed.
Effective Website design is a make-or-break factor in this age of streamlined, sophisticated technology. Customers are looking for professionalism, clarity, accurate branding, and trustworthiness when they arrive at your site. We’ve all heard the statistic that you have four seconds to grab a viewer’s interest. Disappoint them, and they’ll knock on your competition’s door.
Whether your company needs only its basic details displayed online or you’ve got a full ecommerce set-up in mind, efficient site design is key to your success. One important factor to efficient website design is balance: does your design overwhelm the copy representing your company? Be mindful of what your customers will see first. Content balance is important as well; make sure your color scheme isn’t appealing to one target audience while your copy goes after another, or you’ll have conflicting messages.
Here’s where a good Web design company can really come in handy. Many businesses creating their sites in-house can be unaware of the standard design conventions operating successfully on other sites. Designers are well-versed in layout conventions, page organization, and graphic/text ratio. In addition, they will know how to visually balance page graphics and master complementary colors quickly and using the most-advanced resources available to them. A good Web development firm can keep you competitive in every arena so your product has the chance to speak for itself, without any of your site’s elements overwhelming each other.
One area where this is especially helpful is with data flow. If your site is content-intensive, you’ll need to divide the information into smaller sections. A Web designer can help by figuring out ways to organize your information—by creating an index, tabbed sections, or any number of other tactics—to make your information more accessible.
A good firm can also infuse your site with cutting-edge internet marketing practices from the very beginning stages of development. They have the skills in place to make your business competitive in a much shorter timeframe than it takes most businesses to figure out in-house the best marketing strategies for their site. Even the smallest-seeming time advantage could pay off handsomely down the road.
Internet Marketing professionals also tend to be more aware of the latest and greatest technology and services available to advance your business’s online presence. If you arm them with the pertinent information about your target market and intended outcomes, they can zero in on the best ways to help you reach your goals.
By utilizing professional resources and timely expertise to Web designers can help your business compete.
ACU Web Services (www.acuwebservices.com) opened its electronic doors with Austin Coulson at the helm. Web design and Internet marketing have been passions of Austin’s for many years. He has managed marketing efforts for several companies in the technology industry and has been involved with every aspect of several businesses, allowing him to truly consult his clients in many respects.
Article Source: Effective Website Design: When to Call in the Pros
A picture is worth a thousand words. You don’t believe it? What do you understand when you are told such explanation: “a visible mass of droplets or frozen crystals floating in the atmosphere above the surface of the Earth or another planetary body”? And when you are shown the picture of a cloud? Which is easier to understand? The meaning of both explanations is the same but form is completely different.
It’s easier for us to perceive images than mere words and figures. Successful data visualization allows faster understanding, better visibility and an opportunity to discover hidden connections in complex data sets.
One of the most efficient ways to visualize data is flowcharting. It combines words giving them the form of an image which helps to visualize data without losing the words’ sense. Flowcharts can make concepts easy to understand and find solutions. In describing the complex relationships with a variety of choices and results, they ‘re wonderful to keep the important points even throughout different languages. In addition, flowcharts give you the essence of the process flow at a glance.
There are other reasons for using flowcharts.
• Training Materials
Flowcharts are essential when you need to describe the total range of processes needed to implement the task. Text documentation is usually hard to understand as bare words fail to bring the whole idea. When dealing with trainees and newbies such flowcharts are much more effective as they visually stimulating and easy to understand.
• Workflow Management and Improvement
To make sure that you meet your customers’ needs, you must assume control over your processes of businesses. The first stage of workflow management is to define the actual position of your processes by creation initial flowchart . That enables you to analyze your processes for the loss and inefficiency. After you identified sectors for the improvement of process, you then can create new flowcharts to document the coming changes.
• Troubleshooting Guides
Most of us have run into a troubleshooting flowchart at least once in a lifetime. Such flowcharts usually have the form of Decision Trees which gradually narrow the range of possible solutions based on a set of criteria. The more effectively you are able to fit the existing range of problems and their possible solutions into simple Yes/No model the more successfully flowchart helps to solve the difficulties.
Nowadays we have dozens of different on-line and downloadable tools for building attractive flowcharts.
• Origramy Flash Graph Component – flash-based component designed for building, editing and displaying various graphs and diagrams. It is platform independent and doesn’t need installation. What is really great about this tool is that is interactive when every flowchart block can be assigned a separate URL. Dynamic data update is useful for easy content editing without changing the layout. Besides the component supports several languages, can be seen in any browser, reduces load on the server and works with any scripting language. Has SWF and SVG XML export formats.
• EDraw – application that helps the user to create a number of flowcharts, block diagrams and data flow diagrams. EDraw Flowchart Software has abundant flowchart templates, symbols and samples for quickly creating new flow diagrams. The package has a set of tools that make drawing of flowcharts very simple. The tool has wide range of export file formats. The disadvantages are that it works only with Windows.
• Gliffy – is a Flash-based diagramming and flowcharting tool for your web browser. It is often compared to online MS Visio. It has sharing and collaboration features, revision control and the ability to export to SVG or JPEG.
Article Source: Secrets of Data Flow Visualization
After a successful run of the computer system, the next day, when the user sits to work further, the hard drive is found to be crashed. Isn’t the story familiar to hear? Perhaps for some of you, it is. The hard drive failed and there is no operational ability that means no data access and hard disk recovery can make it possible. But, do you know the reason, why this happened? Let’s find out.
About Hard Drive
Hard drive is the creation through mechanical minds which has set of spinning platters that have layers of metal oxide material coated over them to retain data, a shaft mounting those platters, a motor to make the shaft moving, a bunch of read/write heads, actuator arms, electric control board and more. Platters spin at high speed in certain thousands of revolutions per minute, hold magnetic charges which are sensed by the heads so as to have data access privileges.
The read/write heads (each platter surface except the extremes has a head), which are attached to the actuator arm float at about 1-2 micro-inches height from platter surface on a cushion of air. Data flow happens through these heads via electrical connections. Now, with this ideal structure, any distraction implies the data loss is there and hard disk recovery is required.
About Data Loss Trend
With the increasing capacity of hard drives, hard disk recovery is setting more into business and the main reason behind is that data is being stored comparatively in smaller spaces. As compared to the last years, the storage capacity has multiplied itself and as a result has amplified the impact and chances of hard drive failure. Mechanical precision is getting smaller by the day as data is now stored on denser areas.
About Head Crash
A mere push, a contaminant entrance, power surge or any of the apparently small reason can make the head crash and the severest case says that due to scratched platters, data get permanently ruined. The head has come closer to the platter surface, at about 1-2 micro-inches. Now, the standard dust particle size is about 4-8 micro-inches and that of human hair is 10 micro-inches. So you can judge it out, how reckless it could be to have hard disk recovery attempts including opening it in the normal environment.
About Hard Disk Recovery Considerations
Hard disk recovery understands all the points such as what are the internal requirements, what is the suitable way to tackle, which is the precise procedure to have data recovery, the apt surroundings and more. The technicians have now generated tools and techniques which go accordingly with the latest developments in the hard drives.
Hard disk recovery is no more an issue, but with the insufficient ones, still it is. Clean Rooms have been set in order to offer the suitable dust-free surroundings.
About Best Help
Stellar Information Systems Limited is the place where you can sort out all your hard disk recovery queries. The Class 100 Clean Rooms, expertise of technicians, kno-about of all type of hard drive internals, high-tech bunch of tools and techniques, all combine to offer you the best help in hard disk recovery. So you can get maximum of your data recovered, safely and confidentially.
Mahi Sony work as a freelancer and researcher of data recovery & partition recovery Software.
Article Source: Hard Drive Failure Trend and Recovery