What is Google Public DNS?

Google Public DNS is a free, global Domain Name System (DNS) resolution service, that you can use as an alternative to your current DNS provider.
Got Confused…Ok let me explain this is in simple non technical terms (as far as I can). You use Internet right. So how do you access any website, by entering its domain name like www.beingpc.com in any of your favorite browser and hitting enter. But the inside story is different.
When you try to access any webpage in our case www.beingpc.com your computer resolves this domain name (website URL) into IP Address with the help of the Domain NameServer. By default, Windows uses your ISP’s DNS server. 

So in short, to open a website Windows need to resolve the domain name to IP Address by looking it in Domain Serverprovided by your ISP. So the faster your PC resolve the faster you get connected. So this is where Google Public DNS helps, it helps you resolves the domain names into IP Address faster than other.
More Detailed Explanation
Performance comparison of OpenDNS and Google DNS

Setup Google DNS on your Computer
If you would like to setup Google DNS on your Computer than follow the steps below:
Go to Start > Control Panel
Select Network And Internet > Network & Sharing Center
In the left pane click on Change Adapter Settings
Right Click on Local Area Connections and select properties

Adapter setting

Select Internet Protocol Version 4 and click on Properties

Now set the Ip Addresses as below

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The Logon Process

WinLogon
Users must log on to a Windows NTmachine in order to use that NT based machine or network. The logonprocess itself cannot be bypassed, it is mandatory. Once the user has logged on, anaccess token is created (this token will be discussed in more detail later).

This token contains user specific security information, such as:security identifier, group identifiers, user rights and permissions. The user, as well as all processes spawned by the user are identified to the system with this token.

The first step in the WinLogon process is something we are all familiar with,

CTRL+ALT+DEL. This is NT’s default Security Attention Sequence (SAS - The SAS key combo can be changed. We will also discuss that later.). This SAS is a signal to the operating system that someone is trying to logon. After the SAS is triggered, all user mode applications pause until the security operation completes or is cancelled. 

(Note: The SAS is not just a logon operation, this same key combination can be used for logging on, logging off, changing a password or locking the workstation.) The pausing, or closing, of all user mode applications during SAS is a security feature that most people take for granted and dont understand. Due to this pausing of applications, logon related trojan viruses are stopped, keyloggers (programs that run in memory, keeping track of keystrokes, therefor recording someones password) are stopped as well.

The user name is not case sensitive but the password is. After typing in your information and clicking OK (or pressing enter), the WinLogon process supplies the information to the securitysubsystem, which in turn compares the information to the SecurityAccounts Manager (SAM). If the information is compliant with the information in the SAM, an access token is created for the user. The WinLogon takes the access token and passes it onto the Win32 subsytem, which in turn starts the operating systems shell.The shell, as well as all other spawned processes will receive a token. This token is not only used for security, but also allows NTs auditing and logging features to track user usage and access of network resources.

Note: All of the logon components are located in a file known as the Graphical Indetification and Authentication (GINA) module, specifically MSGINA.DLL. Under certain conditions, this file can be replaced, which is how you would change the SAS key combination.
For fine tuning of the WinLogon process, you can refer to theregistry. All of the options for the WinLogon process are contained in the

 HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsNTCurrentVersionWinlogon

area. You can also fine tune the process by using the PolicyEditor.
Logging on to a Domain If an NT machine is a participant on a Domain, you would not only need to login to the local machine, butthe Domain as well. If a computer is a member of a Domain, the WinLogon process is replaced by the NetLogon process.


Image credits: se.edu

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The Finger Command

By default, finger will list the login name, full name, terminal name, and write status
(shown as a “*” before the terminal name if write permission is denied), idle time, login
time, office location, and phone number (if known) for each current user connected to the
network.

Syntax
finger [-l] [User] [@host] [...]

Switches:
-b Brief output format
-f Supresses the printing of the header line.
-i Provides a quick list of users with idle time.
-l Forces long output format.
-p Supresses printing of the .plan file (if present)
-q Provides a quick list of users.
-s Forces short output form.
-w Forces narrow output form.

Examples
To display information for user1 on the computer users.microsoft.com, type the following command: finger user1@users.microsoft.com

To display information for all users on the computer users.microsoft.com, type the following command: finger @users.microsoft.com

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The Netstat Command

Displays active TCP connections, ports on which the computer is listening, Ethernet statistics, the IP routing table, IPv4 statistics (for the IP, ICMP, TCP, and UDP protocols), and IPv6 statistics (for the IPv6, ICMPv6, TCP over IPv6, and UDP over IPv6 protocols). Used without parameters, netstat displays active TCP connections.

Syntax
netstat [-a] [-e] [-n] [-o] [-p Protocol] [-r] [-s] [Interval]

Switches:
-A Shows the addresses of any associated protocol control blocks.
-a Will show the status of all sockets. Sockets associated with network
server processes are normally not shown.
-I Shows the state of the network interfaces.
-m Prints the network memory usage.
-n Causes netstat to show actual addresses as opposed tohostnames or
network names.
-r Prints the routing table.
-s Tells netstat to show the per protocol statistics.
-t Replaces the queue length information with timer information.

Examples
To display both the Ethernet statistics and the statistics for all protocols, type the following command: netstat -e -s

To display the statistics for only the TCP and UDP protocols, type the following

command: netstat -s -p tcp udp

To display active TCP connections and the process IDs every 5 seconds, type the following command: nbtstat -o 5

To display active TCP connections and the process IDs using numerical form, type the following command: nbtstat -n -o

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