Introduction to New Type of Memory Cards - SDHC - Secure Digital High-Capacity
Posted by Joseph Brochin
SDHC (Secure Digital High-Capacity) are new Flash memory cards based on the SDA (Secure Digital Association) 2.00 specification. SDHC provides removable memory storage for compatible digital devices, including cameras, camcorders, PDAs, MP3 players and more.SDHC cards guarantee a minimum sustained data transfer speed, not a maximum speed. There are three available speeds - Class 2, Class 4 and Class 6.There is difference of Data Transfer Rate (DTR) between these classes.
Class 2 devices guaranty a minimum DTR of 2 MB/sec
Class 4 devices guaranty a minimum DTR of 4 MB/secClass 6 devices guaranty a minimum DTR of 6 MB/sec
The device class is specified on the device itself.
The previous versions of SDA specifications did not provide such common standards for sustained data transfer speeds to be shared by all manufacturers. The new speed classification allows users to select card performance based on the needs of particular applications, such as HD video, and other MPEG applications, rather than just a maximum speed rating.
SDHC Cards comes in different capacities ranging from 4 GB-32 GB. Please see the highest capacity supported by your device. SDHC logo on your device does not neccesarily means that your device will support all the capacities that are provided under SDHC cards. There is probabilty that your camera may support only 4 GB of capacity which is also SDHC. Please contact your device manufacturer or refer to your manual for further clarifications.
SDHC cards has the same physical size as SD cards but with higher capacities which cannot be used with SD host devices that do not comply with SDA Specifications Version 2.00.It makes sense,since the same size card with increased capacity would have a different circuit design all together. Also, there is a Sandisk Card Reader that can start supporting SDHC cards after a small firmware upgrade. But only few device versions of that particular model can be upgraded to support SDHC Cards.Host devices complying with SDA Version 2.00 can use both SD Memory Cards and the new SDHC Memory Cards.
Current SD cards complying with Version 1.01 and Version 1.10 use either the FAT16 file system, whereas Version 2.00 uses FAT32. This latest specification was established to support SDHC card applications with higher capacity needs.Remember, only if the approved SDHC logo appears on the card or package, the product is compliant with SDA 2.00 specifications.
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Dealing with the Threat of an SQL Injection Attack
Posted by Joseph Brochin
One of the biggest security issues present in ASP and PHP is the SQL injection. The thing with ASP and PHP is that they have flaws that let web developers make unintentional mistakes in creating SQL queries, leading to vulnerabilities in security. These are easy to fix, but do require some tinkering and research.
Preventing SQL Injections
An effective way to prevent SQL injections is to validate all user inputs thoroughly, identifying meta-characters so you can filter them all out. You must place filters properly so they can remove anything that is not known good data. Utilizing account lockout policies can also help by safeguarding your system from brute-forcing.
Always remember that security validation must be done server-side and never through client-side authentication methods like JavaScript since it can be bypassed by simply turning off JavaScript in the internet browser.
As with numeric input like age, telephone number, credit card number, and so on, values should be processed through special functions to make sure that the entered value only has numbers in it, as well as spaces if necessary. It would do good to limit the number of characters allowed to what is necessary also just to be sure. Do the same with dates, integers, and floats to leave no holes, or just have them in drop-down boxes. If selected through a drop-down box you should still validate the input as a hacker could submit their own html to the server using a text/hidden field instead of a dropdown. Remember that just because your form only lists valid values in a drop-down or radio-group or tick-box, a hacker can still submit any value they want for that field. You should assume that all input fields (regardless of type) can be submitted to the server as if it’s any text value.
For string inputs, on the other hand, it may be necessary to have certain meta-characters allowed. For example, people would have names like O’Neil, so you need to set the apostrophe (single quote) as allowed. In such scenarios, the name should be accepted and perhaps replace the quote with two quotes before putting it into the database just to be safe. It would be helpful to limit the number of characters like with numerical values since an unlimited number of characters can be utilized by someone who is planning to initiate an SQL injection attack.
Threat Management and Damage Control
You can clean up your code as thoroughly and as obsessively as you want, but you will still need assurance. The solution to this problem isn’t free, but is a good long-term investment, especially if your database has very sensitive data like bank account information, contact numbers, email addresses, physical addresses, and so on. In these cases, an SQL injection tool is required to help you with the process.
The best thing you can get is a trusty SQL injection scanner to detect any attacks whenever possible. These are enterprise-level applications available for companies to install onto their servers, so you don’t have to worry much about client-side implications other than making sure that customers can still enter data correctly.
If ever there really was an SQL injection attack, you will have to remove that filth. That is where an SQL injection removal program comes in. Usually available with the SQL injection scanner as a suite, it can be used for damage control so that you can still secure whatever precious data there may be while removing the threat from your system. This is definitely a must-have for emergencies, which makes it a worthwhile investment.
With your SQL injection tool in hand, you can increase security of your website’s database exponentially, thwarting any injection attempts from cracking through. Combining this with careful prevention, you can make sure that data is secure, no matter what. You cannot rely too much on your SQL injection scanner to tell you what’s wrong and your SQL injection removal software to take care of mishaps. Prevention is always better than cure.
For more resources about sql injection tool or even about sql injection removal please review this web page http://www.sqlinjectionscanner.com
Article Source: bb-articles.com