Tuesday, August 30, 2016

Benefits of Software-Defined Networking

And since SDN supports Layer 1 through Layer 3 networking models, there's no need to buy expensive networking devices. In other words, the use of SDN in a production environment can help reduce the costs involved in purchasing expensive hardware.




Overhead Reduction: In a physical environment, the isolation for the customer workloads requires configuring VLANs on separate networking devices, including routers, switches, etc. Since most of the networking is done at the SDN, it is easy for service providers to isolate the customer virtual machines from other customers by using various isolation methods available in the SDN.

Physical vs. Virtual Networking Management:Physical environments necessitate collaboration among different teams to get a task done. For example, if you require some modification at a physical networking device, it would often take a considerable amount of time and teamwork in most organizations before the task can be accomplished.

SDN provides you the ability to control the virtual and physical networking by using a central management tool. A virtual administrator can process the necessary changes without needing to collaborate with different teams.

Managing Virtual Packet Forwarding: SDN can help you forward the virtual packets to a software or physical device running on the network. For example, if a virtual machine needs to access the internet, it becomes easy for virtual administrators to provide the necessary configuration to the virtual machine with minimal effort.

Reduced Downtime: Since SDN helps in virtualizing most of the physical networking devices, it becomes easy to perform an upgrade for one piece rather than needing to do it for several devices. SDN also supports snapshotting the configuration, which helps you quickly recover from any failures caused by the upgrades.

Isolation and Traffic Control: Cloud service providers can benefit from centralizing the networking control using a central management tool. At the same time, SDN provides several isolation mechanisms such as configuring ACLs and firewalls at the virtual machine NIC level. You can also define the traffic rules using the SDN management console, which helps in providing full control over the network traffic.

Extensibility: Since SDN is software-based, it is easy to use SDN API references for vendors to extend the capabilities of an SDN solution by developing applications to control the behavior of networking traffic.

Central Networking Management Tool:SDN can deliver all your networking needs in one product, enabling you to control every piece of an organization's network using a central management tool.

Network administrators often find it difficult to manage a physical router's configuration, and it quickly becomes time consuming and tedious when more than one physical router needs to be managed. SDN simplifies the management of physical routers by providing the management APIs in the SDN console

Friday, August 26, 2016

What is Apex?

Oracle Application Express (Oracle APEX), formerly called HTML DB, is a rapid web application development tool for the Oracle database. Using only a web browser and limited programming experience, you can develop and deploy professional applications that are both fast and secure. Oracle application express combines the qualities of a personal database, productivity, ease of use, and flexibility with the qualities of an enterprise database, security, integrity, scalability, availability and built for the web. Application Express is a tool to build web-based applications and the application development environment is also conveniently web-based. Watch this Application Express Positioning flash demonstration and then try Application Express simply by signing up for an account at apex.oracle.com.




What types of applications can you build with Application Express?
Application Express is a productive tool to build applications that report on database data. Reports are typically hyper text linked with other reports allowing users to navigate through database data in the same way they navigate web sites. Columns in reports can be easily linked to other reports, charts, and data entry forms and it is all done declaratively. An extensive charting engine allows SQL queries to be represented graphically and that allows data to be more effectively communicated. Application Express is also very adept at editing database data and supports a large number of declarative form controls including radio groups, checkboxes, select lists, shuttles, text editors, and date pickers.


When to use Application Express?
Due to its ease of use, Application Express is designed to build opportunistic and departmental applications quickly. These application are deployed on the web with superior performance. Historically, departments, prototypes, and small projects have relied on desktop databases to provide an agile development tool for these smaller scale SMB or departmental application development needs. Desktop databases can become very fragmented because they keep data in too many places, they can be vulnerable or inappropriate for use with sensitive information, and they are typically not web friendly. The browser based design time interface, the declarative programming framework, and simple wizards make Application Express a natural replacement for multi-user desktop databases applications such as Microsoft Access.

SQL Savvy application developers also appreciate the ease with which you can create database applications with little or no web experience. You don't need to learn scripting languages or complex deployment frameworks, you simply write a few queries and choose from ready built user interface themes and form controls to create highly professional, secure, and scalable applications.

Declarative Programming
With Application Express, coding is declarative. That means that no code is generated, no code is compiled, and you interact with wizards and property sheets. The SQL language is used to define reports and charts, so some knowledge of SQL is very helpful. You can optionally write snippets of code using PL/SQL, if procedural logic is needed. Declarative code yields fewer differences between developers and this consistency makes Application Express applications easy to maintain and manage.

Architecture
The Application Express engine renders applications in real time from data stored in database tables.  When you create or extend an application, Oracle Application Express creates or modifies metadata stored in database tables.  When the application is run, the Application Express engine then reads the metadata and displays the application.  Application Express lives completely within your Oracle database.  It is comprised of nothing more than data in tables and large amounts of PL/SQL code.  The essence of Oracle Application Express is approximately 215 tables and 200 PL/SQL objects containing 300,000+ lines of code.

To provide stateful behavior within an application, Oracle Application Express transparently manages session state in the database.  Application developers can get and set session state using simple substitutions as well as standard SQL bind variable syntax.

To access the Oracle Application Express engine within the Oracle database you must configure the Oracle HTTP Server(Apache) containing the mod_plsql plug-in . The plugin functions as communication broker between the Web server and the Oracle Application Express objects in the Oracle database. This maps browser requests into database stored procedure calls. The following graphic illustrates the Oracle Application Express architecture using Oracle HTTP Server and mod_plsql.

Oracle Application Express using the Oracle HTTP Server (Apache) with mod_plsql
With Oracle Database 11.1, you can remove Oracle HTTP Server (Apache) from the architecture and replace it with the embedded PL/SQL gateway. The embedded PL/SQL gateway runs in the XML DB HTTP server in the Oracle database and includes the core features of mod_plsql, but does not require the Oracle HTTP Server powered by Apache. The graphic below illustrates the Oracle Application Express architecture using the Embedded PL/SQL Gateway.

Oracle Application Express using the Embedded PL/SQL Gateway
Converting Applications
Oracle Application Express Application Migration Workshop (Application Migration) enables you to convert Oracle Forms and Microsoft Access applications and generate an Oracle Application Express application from the retrieved objects.

Oracle Forms modernization projects are often undertaken to convert legacy applications to the latest Oracle Database version and enable developers to satisfy user demands for greater user interactivity and Web 2.0 capabilities




Key Features
The sections that follow describe key features of Oracle Application Express, including:

Reporting
Forms
Charting
PDF Printing
Web Services
Spreadsheet Upload
Session State Management
User Interface Themes
Flow Control & Navigation
Conditionality on all Components
External Interfaces & Extensibility
Declarative BLOB Support
Optional Runtime-Only Installation
Security
SQL Workshop Tools
Supporting Objects Utility
Performance
Packaged Applications
Hosted Development

Saturday, July 30, 2016

Six Benefits Of IPv6

With IPv6, everything from appliances to automobiles can be interconnected. But an increased number of IT addresses isn't the only advantage of IPv6 over IPv4. In honor of World IPv6 Day, here are six more good reasons to make sure your hardware, software, and services support IPv6.
With IPv6, everything from appliances to automobiles can be interconnected. But an increased number of IT addresses isn't the only advantage of IPv6 over IPv4. In honor of World IPv6 Day, here are six more good reasons to make sure your hardware, software, and services support IPv6.


More Efficient Routing
IPv6 reduces the size of routing tables and makes routing more efficient and hierarchical. IPv6 allows ISPs to aggregate the prefixes of their customers' networks into a single prefix and announce this one prefix to the IPv6 Internet. In addition, in IPv6 networks, fragmentation is handled by the source device, rather than the router, using a protocol for discovery of the path's maximum transmission unit (MTU).
More Efficient Packet Processing
IPv6's simplified packet header makes packet processing more efficient. Compared with IPv4, IPv6 contains no IP-level checksum, so the checksum does not need to be recalculated at every router hop. Getting rid of the IP-level checksum was possible because most link-layer technologies already contain checksum and error-control capabilities. In addition, most transport layers, which handle end-to-end connectivity, have a checksum that enables error detection.
Directed Data Flows
IPv6 supports multicast rather than broadcast. Multicast allows bandwidth-intensive packet flows (like multimedia streams) to be sent to multiple destinations simultaneously, saving network bandwidth. Disinterested hosts no longer must process broadcast packets. In addition, the IPv6 header has a new field, named Flow Label, that can identify packets belonging to the same flow.
Simplified Network Configuration
Address auto-configuration (address assignment) is built in to IPv6. A router will send the prefix of the local link in its router advertisements. A host can generate its own IP address by appending its link-layer (MAC) address, converted into Extended Universal Identifier (EUI) 64-bit format, to the 64 bits of the local link prefix.
Support For New Services
By eliminating Network Address Translation (NAT), true end-to-end connectivity at the IP layer is restored, enabling new and valuable services. Peer-to-peer networks are easier to create and maintain, and services such as VoIP and Quality of Service (QoS) become more robust.
Security
IPSec, which provides confidentiality, authentication and data integrity, is baked into in IPv6. Because of their potential to carry malware, IPv4 ICMP packets are often blocked by corporate firewalls, but ICMPv6, the implementation of the Internet Control Message Protocol for IPv6, may be permitted because IPSec can be applied to the ICMPv6 packets.

Tuesday, May 10, 2016

What is RemoteApp?

RemoteApp enables you to make programs that are accessed remotely through Remote Desktop Services appear as if they are running on the end user's local computer. These programs are referred to as RemoteApp programs. Instead of being presented to the user in the desktop of the Remote Desktop Session Host (RD Session Host) server, the RemoteApp program is integrated with the client's desktop. The RemoteApp program runs in its own resizable window, can be dragged between multiple monitors, and has its own entry in the taskbar. If a user is running more than one RemoteApp program on the same RD Session Host server, the RemoteApp program will share the same Remote Desktop Services session.


Why use RemoteApp?

RemoteApp can reduce complexity and reduce administrative overhead in many situations, including the following:
  • Branch offices, where there may be limited local IT support and limited network bandwidth.
  • Situations where users need to access programs remotely.
  • Deployment of line-of-business (LOB) programs, especially custom LOB programs.
  • Environments, such as "hot desk" or "hoteling" workspaces, where users do not have assigned computers.
  • Deployment of multiple versions of a program, particularly if installing multiple versions locally would cause conflicts.
****Run app in other os(Mac Linux FreeBsd Android Windows Phone......)

Monday, April 25, 2016

12 Foods That Lower Cholesterol Naturally

1. Oats
If you're looking to lower your cholesterol, the key may be simply changing your morning meal. Switching up your breakfast to contain two servings of oats can lower LDL cholesterol (the bad kind) by 5.3% in only 6 weeks. The key to this cholesterol buster is beta-glucan, a substance in oats that absorbs LDL, which your body then excretes. Banish bland oats with this dessert-worthy ginergersnap oatmeal recipe.

2. Red wine
Scientists are giving us yet another reason to drink to our health. It turns out that high-fiber Tempranillo red grapes, used to make red wine like Rioja, may actually have a significant effect on lowering cholesterol levels. A study conducted by the department of metabolism and nutrition at Universidad Complutense de Madrid in Spain found that when individuals consumed the same grape supplement found in red wine, their LDL levels decreased by 9%. In addition, those who had high cholesterol going into the study saw a 12% drop in LDL. So go ahead and drink a glass for that lowering cholesterol benefit.

3. Salmon & fatty fish
Omega-3 fats are one of the natural health wonders of the world and have been shown to ward off heart disease, dementia, and many other diseases. Now these fatty acids can add yet another health benefit to their repertoire: lowering cholesterol. According to research from Loma Linda University, replacing saturated fats with omega-3s like those found in salmon, sardines, and herring can raise good cholesterol as much as 4%. (Here's everything you need to know about buying the healthiest fish possible.)


Are you at risk for the #1 cause of heart-related death?

4. Nuts
If you're looking for that perfect snack food that lowers cholesterol levels, research shows that you should get cracking! In a study published by the American Journal of Clinical Nutrition, people who noshed on 1.5 ounces of whole walnuts 6 days a week for 1 month lowered their total cholesterol by 5.4% and LDL cholesterol by 9.3%. Almonds and cashews are other good options. However, while nuts are heart healthy, they're also high in calories, so practice portion control—1.5 ounces is about a shot glass and a half. Use a shot glass to measure out your portion so you can see exactly how it looks.



5. Tea


Photo by gojack/Getty Images

While tea has become well known for its cancer-fighting antioxidants, it is also a great defense against LDL cholesterol levels. According to research conducted with the USDA, black tea has been shown to reduce blood lipids by up to 10% in only 3 weeks. These findings were concluded in a larger study of how tea may also help reduce the risk of coronary heart disease. (Here's how to make the perfect cup of tea every time.)

MORE: The Healthiest Teas To Drink From Morning To Night

6. Beans
Beans, beans—they really are good for your heart. Researchers at Arizona State University Polytechnic found that adding ½ cup of beans to soup lowers total cholesterol, including LDL, by up to 8%. The key to this heart-healthy food that lowers cholesterol is its abundance of fiber, which has been shown to slow the rate and amount of absorption of cholesterol in certain foods. Try black, kidney, or pinto beans; each supplies about one-third of your daily fiber needs.

7. Chocolate
Yes! Chocolate is one of the foods that lowers cholesterol. This powerful antioxidant helps build HDL cholesterol levels. In a 2007 study published in AJCN, participants who were given cocoa powder had a 24% increase in HDL levels over 12 weeks, compared with a 5% increase in the control group. Remember to choose the dark or bittersweet kind. Compared to milk chocolate, it has more than 3 times as many antioxidants, which prevent blood platelets from sticking together and may even keep arteries unclogged.

8. Margarine
Switching to a margarine with plant sterols, such as Promise activ or Benecol, could help lower cholesterol. Plant sterols are compounds that reduce cholesterol absorption; a study published in AJCN found that women who had a higher plant sterol–based diet were able to lower total cholesterol by 3.5%.

9. Garlic
Aside from adding zing to almost any dish, garlic makes the list of foods that lower cholesterol; it's also been found to prevent blood clots, reduce blood pressure, and protect against infections. Now research finds that it helps stop artery-clogging plaque at its earliest stage by keeping cholesterol particles from sticking to artery walls. Try for two to four fresh cloves a day of this powerful cholesterol fighting food.





10. Olive oil


Photo by Okea/Getty Images

Good news: This common cooking ingredient can help your health. Olive oil is full of heart-healthy monounsaturated fatty acids (MUFAs), which lower LDL cholesterol—and have the welcome side effect of trimming belly fat. Use it to make your own salad dressings, marinate chicken and fish, or roast vegetables.

11. Spinach
This popular green food that lowers cholesterol contains lots of lutein, the sunshine-yellow pigment found in dark green leafy vegetables and egg yolks. Lutein already has a "golden" reputation for guarding against age-related macular degeneration, a leading cause of blindness. Now research suggests that just ½ cup of a lutein-rich food daily also guards against heart attacks by helping artery walls "shrug off" cholesterol invaders that cause clogging. Look for bags of baby spinach leaves that you can use for salads or pop in the microwave for a quick side dish.

MORE: 3 Recipes To Take Your Love Of Spinach To A Whole New Level

12. Avocado
Avocados are a great source of heart-healthy monounsaturated fat, a type of fat that may actually help raise HDL cholesterol while lowering LDL. And, more than any other fruit, this delectable food packs cholesterol-smashing beta-sitosterol, a beneficial plant-based fat that reduces the amount of cholesterol absorbed from food. Since avocados are a bit high in calories and fat (300 calories and 30 g fat per avocado), use them in moderation. (We suggest these 8 unique and insanely tasty avocado recipes.)

Thursday, April 21, 2016

integrating barcode scanner into php application?

PHP can be easily utilized for reading bar codes printed on paper documents. Connecting manual barcode reader to the computer via USB significantly extends usability of PHP (or any other web programming language) into tasks involving document and product management, like finding a book records in the database or listing all bills for a particular customer.

Following sections briefly describe process of connecting and using manual bar code reader with PHP.



What is a bar code reader (scanner)

Bar code reader is a hardware pluggable into computer that sends decoded bar code strings into computer. The trick is to know how to catch that received string. With PHP (and any other web programming language) the string will be placed into focused input HTML element in browser. Thus to catch received bar code string, following must be done:

just before reading the bar code, proper input element, such as INPUT TEXT FIELD must be focused (mouse cursor is inside of the input field). once focused, start reading the code when the code is recognized (bar code reader usually shortly beeps), it is send to the focused input field. By default, most of bar code readers will append extra special character to decoded bar code string called CRLF (ENTER). For example, if decoded bar code is "12345AB", then computer will receive "12345AB". Appended character (or ) emulates pressing the key ENTER causing instant submission of the HTML form:



<form action="search.php" method="post">
    <input name="documentID" onmouseover="this.focus();" type="text">
</form>


PHP can be easily utilized for reading bar codes printed on paper documents. Connecting manual barcode reader to the computer via USB significantly extends usability of PHP (or any other web programming language) into tasks involving document and product management, like finding a book records in the database or listing all bills for a particular customer.

Following sections briefly describe process of connecting and using manual bar code reader with PHP.

The usage of bar code scanners described in this article are in the same way applicable to any web programming language, such as ASP, Python or Perl. This article uses only PHP since all tests have been done with PHP applications.
What is a bar code reader (scanner)

Bar code reader is a hardware pluggable into computer that sends decoded bar code strings into computer. The trick is to know how to catch that received string. With PHP (and any other web programming language) the string will be placed into focused input HTML element in browser. Thus to catch received bar code string, following must be done:

just before reading the bar code, proper input element, such as INPUT TEXT FIELD must be focused (mouse cursor is inside of the input field). once focused, start reading the code when the code is recognized (bar code reader usually shortly beeps), it is send to the focused input field. By default, most of bar code readers will append extra special character to decoded bar code string called CRLF (ENTER). For example, if decoded bar code is "12345AB", then computer will receive "12345AB". Appended character (or ) emulates pressing the key ENTER causing instant submission of the HTML form:

<form action="search.php" method="post">
    <input name="documentID" onmouseover="this.focus();" type="text">
</form>
Choosing the right bar code scanner

When choosing bar code reader, one should consider what types of bar codes will be read with it. Some bar codes allow only numbers, others will not have checksum, some bar codes are difficult to print with inkjet printers, some barcode readers have narrow reading pane and cannot read for example barcodes with length over 10 cm. Most of barcode readers support common barcodes, such as EAN8, EAN13, CODE 39, Interleaved 2/5, Code 128 etc.

For office purposes, the most suitable barcodes seem to be those supporting full range of alphanumeric characters, which might be:

code 39 - supports 0-9, uppercased A-Z, and few special characters (dash, comma, space, $, /, +, %, *)
code 128 - supports 0-9, a-z, A-Z and other extended characters
Other important things to note:

make sure all standard barcodes are supported, at least CODE39, CODE128, Interleaved25, EAN8, EAN13, PDF417, QRCODE.
use only standard USB plugin cables. RS232 interfaces are meant for industrial usage, rather than connecting to single PC.
the cable should be long enough, at least 1.5 m - the longer the better.
bar code reader plugged into computer should not require other power supply - it should power up simply by connecting to PC via USB.
if you also need to print bar code into generated PDF documents, you can use TCPDF open source library that supports most of common 2D bar codes.


installing scanner drivers

Installing manual bar code reader requires installing drivers for your particular operating system and should be normally supplied with purchased bar code reader.

Once installed and ready, bar code reader turns on signal LED light. Reading the barcode starts with pressing button for reading.








step 3
Conclusion

It seems, that utilization of PHP (and actually any web programming language) for scanning the bar codes has been quite overlooked so far. However, with natural support of emulated keypress (ENTER/CRLF) it is very easy to automate collecting & processing recognized bar code strings via simple HTML (GUI) fomular.

The key is to understand, that recognized bar code string is instantly sent to the focused HTML element, such as INPUT text field with appended trailing character ASCII 13 (=ENTER/CRLF, configurable option), which instantly sends input text field with populated received barcode as a HTML formular to any other script for further processing.



Monday, April 11, 2016

Fatty Liver Disease

Some fat in your liver is normal. But if it makes up more than 5%-10% of the organ's weight, you may have fatty liver disease. If you're a drinker, stop. That's one of the key causes of the condition.

There are two main types of fatty liver disease:




Alcoholic liver disease (ALD)
Nonalcoholic fatty liver disease (NAFLD)

Alcoholic Liver Disease (ALD)

You can get alcoholic liver disease from drinking lots of alcohol. It can even show up after a short period of heavy drinking.

Genes that are passed down from your parents may also play a role in ALD. They can affect the chances that you become an alcoholic. And they can also have an impact on the way your body breaks down the alcohol you drink.

Other things that may affect your chance of getting ALD are:

Hepatitis C (which can lead to inflammation in your liver)
Too much iron in your body

Being obese

Nonalcoholic Fatty Liver Disease (NAFLD)

It's not clear what causes this type of fatty liver disease. It tends to run in families.

It's also more likely to happen to those who are middle-aged and overweight or obese. People like that often have high cholesterol and diabetes as well.

Other causes are:

Medications
Viral hepatitis
Autoimmune or inherited liver disease
Fast weight loss
Malnutrition

Some studies show that too much bacteria in your small intestine and other changes in the intestine may be linked to nonalcoholic fatty liver disease.


Diagnosis of Fatty Liver Disease
You might find out that you have the disease when you get a routine checkup. Your doctor might notice that your liver is a little larger than usual.

Other ways your doctor might spot the disease are:

Blood tests. A high number of certain enzymes could mean you've got fatty liver.

Ultrasound. It uses soundwaves to get a picture of your liver.


Treatment of Fatty Liver Disease


There is no specific treatment. But you can improve your condition by managing your diabetes, if you have it.

If you have alcoholic liver disease and you are a heavy drinker, quitting is the most important thing you can do. Talk to your doctor about how to get help. If you don't stop you could get complications like alcoholic hepatitis or cirrhosis.

Even if you have nonalcoholic fatty liver disease, it can help to avoid drinking. If you are overweight or obese, do what you can to gradually lose weight -- no more than 1 or 2 pounds a week.

Eat a balanced and healthy diet and get regular exercise. Limit high-carb foods such as bread, grits, rice, potatoes, and corn. And cut down on drinks with lots of sugar like sports drinks and juice.

http://www.webmd.com/hepatitis/fatty-liver-disease?page=2