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Securing Ajax and Web Services

It is undeniable that Web services and AJAX-ified interfaces are the trend now. Application that utilizes internet to retrieve data (such as mobile application or other thin client) uses web services alongside with its data format. AJAX-ified interface and website gives a modern and edgy look can make websites more attractive and can create great impression to the users.

However the issue of the web application security would still remain the same, if not more challenging, since there are so many ways to exploit the vulnerability of websites that utilizes Web Services and AJAX transfers on the background.

Therefore, it is imperative to use the right technique in order to evaluate the security of these services before deploying them out in the open.

For that matter, now I’m currently reading Ajax Security (Hoffman,B. & Sullivan, B.) and Securing Ajax applications (Wells, C.) which in my opinion is a pretty good start for somebody like me to understand common methods for securing web services and websites which uses AJAX heavily.

Hopefully the situation would improved as there are a lot of campaigns around to raise the state of awareness of web application security.

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How to limit cpu usage for a process with cpulimit (Ubuntu / Debian server)

cpulimit is a tool that can be used to limit cpu usage (throttle cpu usage) for a single process (by its PID). cpulimit is useful to ensure that a single process would not hogs the cpu cycles, which can be use by other processes. cpulimit is different from ‘nice’ as it limits the real cpu usage for a process, while ‘nice’ controls scheduling priorities for a particular process.

How to use cpulimit?
Basic usage:
[bash]
cpulimit -p [pid] -l [ cpu percentage]
cpulimit -p 12345 -l 25
[/bash]

Running cpulimit on background:

[bash]
cpulimit -p 12345 -l 25 -z -b
[/bash]

Note: The cpu percentage is the same one as reported by the ‘top’ command.

cpulimit can be installed from Ubuntu and Debian 6.0 (Squeeze) repository through apt-get. The official website of cpulimit is http://limitcpu.sf.net

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Pingness.com: Free service to monitor website uptime

It is undeniable that uptime is important for business and personal websites. For example, a website with low uptime may mean that the host is having technical problem or the web server is overwhelmed by client requests (serving web pages may incur a lot of overhead)

Pingness.com service does not require sign-up, you need to submit your email address and website url, and pingness will send reports of your site downtime (if any) and when the website is back-online.

pingness