1. What is your opinion about the information safety problem in outsourcing?
It's definitely not easy giving up control or handing over sensitive information to complete strangers. On one hand, it's nice to be able to do everything IT related in-house. You control access and you control how and when things get done. On the other hand, any smart businessperson knows it's practically impossible for one department or person to do everything and do it well.
Think Like A Thief
IT-related issues should be viewed from a hacker's perspective. This means considering what can happen if your confidential information gets into the wrong hands. Do you have digital assets worthy of abuse? What negative consequences would occur if they were abused? Is your job going to be on the line if your company makes the headlines?
Who has access?
Most outsourced IT services require someone somewhere to have full access to a portion, if not all, of your digital goods. For instance, desktop support professionals will likely need administrative rights to your workstations. This likely translates into full access to corporate data stored on local drives and, potentially, network shares. Consider what an IT auditor or security consultant may gather during the days, weeks or months onsite perusing your systems. It's limitless and it only takes one miscreant to cause a lot of damage.
Data control
It's one thing to understand that outsourced IT service providers have access to corporate data, but it's quite another to know what they're actually doing with that data. Are they storing the data on their servers, laptops, CDs or USB drives? Are they printing hard copies? The answer is likely yes for both. Clients should expect to turn at least some of their information over and need to be informed of why it's needed and how it's going to be used.
Information protection
You also have to consider how they're protecting this information -- if at all. What are they doing with your information? Are they sharing it with colleagues or competitors? Keeping it to sell in a few years? Even if the people you're outsourcing your IT services to are bound by contract to protect your information, they may not have your best interests in mind, or they may be just plain sloppy. Consider what a person has to lose if he ends up leaving the company or getting out of the IT business altogether. Probably not much. The probability of sales data, source code or patient information being used for ill-gotten gains is pretty low, but it can happen.
Basic instincts
Strong contracts and clean criminal records are not a perfect indicator of safe and sound IT services, so don't rely solely on them. It's also unrealistic to attempt to completely control where your sensitive data is housed and what a third-party does with it. Whether you're for or against outsourcing IT services, you'll have to do it eventually. Do your best to find good people to do business with – preferably through referrals – and trust your instincts.
So, to answer the question, is outsourcing IT services worth the security risk? That depends on organization. While I do believe it's worth the risk, it's not a decision that should be made lightly.

2. What is the same and difference among insourcing, outsourcing and selfsourcing?
The primary difference between outsourcing, insourcing and self-sourcing is the method in which work is divided between various companies or departments for strategic purposes. Other differences between these three business practices include control, costs, location and resources.