Top Security Tools

Nessus::Formerly open source vulnerability assessment tool 
Nessus is a remote security scanner for Linux, BSD, Solaris, and other Unices. It is plug-in-based, has a GTK interface, and performs over 1200 remote security checks. It allows for reports to be generated in HTML, XML, LaTeX, and ASCII text, and suggests solutions for security problems. It was open source for many years, but they turned proprietary in late 2005

TCPDump / WinDump::The classic sniffer for network monitoring and data acquisition
Tcpdump is a well-known and well-loved text-based network packet analyzer ("sniffer"). It can be used to print out the headers of packets on a network interface that matches a given expression. You can use this tool to track down network problems or to monitor network activities. There is a separate Windows port named WinDump. TCPDump is also the source of the Libpcap/WinPcap packet capture library, which is used by Nmap among many other utilities. Note that many users prefer the newer Ethereal sniffer.

GFI LANguard::A commercial network security scanner for Windows
LANguard scans networks and reports information such as service pack level of each machine, missing security patches, open shares, open ports, services/applications active on the computer, key registry entries, weak passwords, users and groups, and more. Scan results are outputted to an HTML report, which can be customized/queried. Apparently a limited free version is available for non-commercial/trial use.

 
 OpenSSH / SSH::A secure way to access remote computers
Ssh (Secure Shell) is a program for logging into or executing commands on a remote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP/IP ports can also be forwarded over the secure channel. It is intended as a replacement for rlogin, rsh and rcp, and can be used to provide rdist, and rsync with a secure communication channel. OpenSSH is affiliated with the OpenBSD project, though a portable version runs on most UNIX systems. Note that the SSH.Com link above costs money for some uses, while OpenSSH is always free. Windows users may want to try the free PuTTY SSH Client or the nice terminal-based port of OpenSSH that comes with Cygwin. There are dozens of other clients (free or prorietary) available for most platforms - here is a huge list.

Proxy Servers HIDE IP address from WEB NOT other INFORMATION

The exchange of information in Internet is made by the "client - server" model. A client sends a request (what files he needs) and a server sends a reply (required files). For close cooperation (full understanding) between a client and a server the client sends additional information about itself: a version and a name of an operating system, configuration of a browser (including its name and version) etc. This information can be necessary for the server in order to know which web-page should be given (open) to the client. There are different variants of web-pages for different configurations of browsers. However, as long as web-pages do not usually depend on browsers, it makes sense to hide this information from the web-server.

What your browser transmits to a web-server:
a name and a version of an operating system
a name and a version of a browser
configuration of a browser (display resolution, color depth, java / javascript support, ...)
IP-address of a client
Other information

The most important part of such information (and absolutely needless for a web-server) is information about IP-address. Using your IP it is possible to know about you the following:
a country where you are from
a city
your provider?s name and e-mail
your physical address

Information, transmitted by a client to a server is available (accessible) for a server as environment variables. Every information unit is a value of some variable. If any information unit is not transmitted, then corresponding variable will be empty (its value will be undetermined).

These are some environment variables:

REMOTE_ADDR ? IP address of a client

HTTP_VIA ? if it is not empty, then a proxy is used. Value is an address (or several addresses) of a proxy server, this variable is added by a proxy server itself if you use one.

HTTP_X_FORWARDED_FOR ? if it is not empty, then a proxy is used. Value is a real IP address of a client (your IP), this variable is also added by a proxy server if you use one.

HTTP_ACCEPT_LANGUAGE ? what language is used in browser (what language a page should be displayed in)

HTTP_USER_AGENT ? so called "a user?s agent". For all browsers this is Mozilla. Furthermore, browser?s name and version (e.g. MSIE 5.5) and an operating system (e.g. Windows 98) is also mentioned here.

HTTP_HOST ? is a web server?s name

This is a small part of environment variables. In fact there are much more of them (DOCUMENT_ROOT, HTTP_ACCEPT_ENCODING, HTTP_CACHE_CONTROL, HTTP_CONNECTION, SERVER_ADDR, SERVER_SOFTWARE, SERVER_PROTOCOL, ...). Their quantity can depend on settings of both a server and a client.

These are examples of variable values:

REMOTE_ADDR = 194.85.1.1
HTTP_ACCEPT_LANGUAGE = ru
HTTP_USER_AGENT = Mozilla/4.0 (compatible; MSIE 5.0; Windows 98)
HTTP_HOST = www.webserver.ru
HTTP_VIA = 194.85.1.1 (Squid/2.4.STABLE7)
HTTP_X_FORWARDED_FOR = 194.115.5.5

Anonymity at work in Internet is determined by what environment variables "hide" from a web-server.

If a proxy server is not used, then environment variables look in the following way:

REMOTE_ADDR = your IP
HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined

According to how environment variables "hided" by proxy servers, there are several types of proxies
Transparent Proxies

They do not hide information about your IP address:

REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = your IP

The function of such proxy servers is not the improvement of your anonymity in Internet. Their purpose is information cashing, organization of joint access to Internet of several computers, etc.
Anonymous Proxies

All proxy servers, that hide a client?s IP address in any way are called anonymous proxies

Simple Anonymous Proxies

These proxy servers do not hide a fact that a proxy is used, however they replace your IP with its own:
REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = proxy IP

These proxies are the most widespread among other anonymous proxy servers.

Distorting Proxies

As well as simple anonymous proxy servers these proxies do not hide the fact that a proxy server is used. However a client?s IP address (your IP address) is replaced with another (arbitrary, random) IP:

REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = random IP address
High Anonymity Proxies

These proxy servers are also called "high anonymity proxy". In contrast to other types of anonymity proxy servers they hide a fact of using a proxy:

REMOTE_ADDR = proxy IP
HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined

That means that values of variables are the same as if proxy is not used, with the exception of one very important thing ? proxy IP is used instead of your IP address.
Summary

Depending on purposes there are transparent and anonymity proxies. However, remember, using proxy servers you hide only your IP from a web-server, but other information (about browser configuration) is accessible!

DATA SECURITY

                          Data security  is the means of ensuring that data is kept safe from corruption and that access to it is suitably controlled.Thus data security helps to ensure privacy. It also helps in protecting personal data.

Data Security Technologies::

Full Disk Encryption

Full disk encryption refers to disk encryption technology that encrypts all of the data on the disk or a hard disk drive. Full disk encryption typically takes form in either software (see disk encryption software or hardware (see disk encryption hardware). Full Disk Encryption is often referred to as "FDE," and the combination of hardware and software full disk encryption is often referred to as "end-point full disk encryption," or "end-based full disk encryption.

Strong User Authentication

Single sign-on refers to authentication allowing users to log onto programs, files, folders, and computers once and without being requested to do so again. Single sign-on technology typically is adopted within a "strong user authentication" sense. That is, users are asked to sign-on with multiple factors of authentication. For example:
#password
#smartcard
#fingerprint
#One-time password

International Laws and Standards

                       In the UK, the Data Protection Act is used to ensure that personal data is accessible to those whom it concerns, and provides redress to individuals if there are inaccuracies. This is particularly important to ensure individuals are treated fairly, for example for credit checking purposes. The Data Protection Act states that only individuals and companies with legitimate and lawful reasons can process personal information and cannot be shared.

International Standards

The International Standard ISO/IEC 17799 covers data security under the topic of information security, and one of its cardinal principles is that all stored information, i.e. data, should be owned so that it is clear whose responsibility it is to protect and control access to that data.

The Trusted Computing Group is an organization that helps standardize computing security technologies.

NETWORK SECURITY

Network security consists of the provisions made in an underlying computer network infrastructure, policies adopted by the network administrator to protect the network and the network-accessible resources from unauthorized access and the effectiveness (or lack) of these measures combined together.

Comparison with computer security

Securing network infrastructure is like securing possible entry points of attacks on a country by deploying appropriate defense. Computer security is more like providing means to protect a single PC against outside intrusion. The former is better and practical to protect the civilians from getting exposed to the attacks. The preventive measures attempt to secure the access to individual computers--the network itself--thereby protecting the computers and other shared resources such as printers, network-attached storage connected by the network. Attacks could be stopped at their entry points before they spread. As opposed to this, in computer security the measures taken are focused on securing individual computer hosts. A computer host whose security is compromised is likely to infect other hosts connected to a potentially unsecured network. A computer host's security is vulnerable to users with higher access privileges to those hosts.

Attributes of a secure network

Network security starts from authenticating any user, most likely a username and a password. Once authenticated, a stateful firewall enforces access policies such as what services are allowed to be accessed by the network users. Though effective to prevent unauthorized access, this component fails to check potentially harmful contents such as computer worms being transmitted over the network. An intrusion prevention system (IPS)  helps detect and prevent such malware. IPS also monitors for suspicious network traffic for contents, volume and anomalies to protect the network from attacks such as denial of service. Communication between two hosts using the network could be encrypted to maintain privacy. Individual events occurring on the network could be tracked for audit purposes and for a later high level analysis.

Honeypots, essentially decoy network-accessible resources, could be deployed in a network as surveillance and early-warning tools. Techniques used by the attackers that attempt to compromise these decoy resources are studied during and after an attack to keep an eye on new exploitation techniques. Such analysis could be used to further tighten security of the actual network being protected by the honeypot.