Windows 7 is designed for user's idea, performance, product trust, and security. In particular, MS improved multiple security functions such as Windows Vista's UAC(User Account Control), Windows firewall, Internet Explorer security mode, and etc. by new technologies "BitLocker To Go", "AppLocker" for user convenience.

1. Windows 7 for user convenience – User Account Control

MS applied UAC functions to the previous version, Windows Vista, for the first time, and helped to reduce the malicious code infections around 60%, on the other hand, it caused Internet banking, e-government services, online games, and etc. due to lack of compatibility. Also, frequent security check window brought about user's inconvenience.

In Windows 7, therefore, the security check window pops-up when Windows settings are modified without user agreement only. Also, the new functions such as notifying on program's modification and notifying without desktop's blurring have been added to Windows 7.

Some of PC-unfamiliar users may not be able to deal with UAC as well, but they get some help by asking to security experts how to set UAC. UAC is designed for user convenience and security strengthening, thus how useful the UAC is the user's final decision.

2. Windows Firewall

Windows 7 supports improved networking function, thus user can access/maintain network easily regardless of network location or types. Moreover, user can customize firewall settings by using Windows 7 provided filtering platform.

Let's get to know about Direct Access which is the one of the Windows 7 firewall functions. This function makes users to be able to access to network (=Intranet) directly.

Previous VPN method required VPN device and additional settings for network access from outside, but in Windows 7, it is available by using current public Internet without VPN device. Windows 7 use VPN's certificate functions, IPSec-ESP, IP-TLS, thus user can reduce costs by maintaining public VPN level's security.

Also, control for intranet access has been strengthened through multilevel authorizations like smart card method, and network manager can set policies/resources depending on certain users easily. In the past, these new functions were available in public VPN, not in Windows, but now Windows 7 supports them and it seems to be improved a lot for personal user's security.

3. Encryption against unexpected situation – BitLocker To Go

Sometimes people lose their laptops unintentionally, and through this case, many saved important information could be leaked out to others. Thus Windows 7 studied out for security against unexpected situation, and finally it does provide storage encryption by using hardware supported trustable platform module (TPM). User can encrypt entire disk relatively easy way, but just it takes some time. Also, Windows 7 supports portable device's encryption unlike Windows Vista.

There are some pre-conditions for using BitLocker To Go function.
First, BitLocker To Go can be used on Windows 7 Ultimate and Enterprise versions only. Also, it has condition precedent for supporting previous versions such as Vista, XP. In Windows 7, write, read, execute, and all other functions are available after entering password, but in the previous version of Windows, only read function is available by using BitLocker To Go reader. If users try to write something to disk, drive's space is marked as full and access is restricted. For preventing, of course, users must remember the password.

Personal users may use BitLocker To Go partially, but enterprises will use this function essentially for the important information work. Obviously it is a good function, but it missed a good opportunity to be an industry standard due to supporting certain product group only. Similar features of the free software, Truecrypt's development can be expected, instead.

4. Another security for enterprise – AppLocker

In the common network or enterprises which use certain shared groups, even a single PC's problem could be spread to entire company very easily.

AppLocker controls application, and it can be helpful for company's security. Installing unauthorized software can be caused software trouble between illegal software and existing one, furthermore, if an employee executes a malicious programs by mistake, the security problems of the entire company may be inestimable huge than usual thought.

By using AppLocker, security manager can control policies like white list, black list, grey list, by user or group. Also, monitoring for DLL file, controlling of indiscreet ActiveX installation are available.

For using AppLocker effectively, security manager should check many existing applications and do pre-test undefined software troublesomely, but if the initial settings is done well, the entire company could be kept in safe against various security attacks.

5. Conclusion

Windows 7 has been improved many aspects for general users to enterprise's IT infrastructure, and even though many security restriction could cause low product performance, certainly it seems to be done a lot of work for getting the best result by understanding the security's specific features.

By adding new security functions like UAC, firewall, BitLocker To Go, AppLocker, Windows 7 may help a lot for system security than previous version of Windows OS; however, everyday new security threats, Exploits, malicious codes are occurred, and they threaten our system directly or indirectly, thus it cannot say "perfect".
By using Windows Defender which is the Windows 7 default malicious code remover tool, user can lower the threat level against malicious code attacks, but definitely there is a difference between professional vaccine programs.

Apart from security functions, users must install/use vaccine programs such as ViRobot, and won't forget that is the safest way to keep the system against multiple virus, malicious codes and etc.

http://technet.microsoft.com/en-us/library/cc732774(WS.10).aspx#BKMK_SystemRequirements