internet connection sharing (ICS)

Overview of ICS

If you have multiple computers, you can use ICS to allow you and others on your local area network (LAN) to perform different tasks simultaneously. For example, one person can send and receive e-mail messages, while another person downloads a file, and another person browses the Internet. You can also gain access to your corporate e-mail accounts from a client computer while others on your LAN cannot. With ICS You can use Web-enabled programs (such as downloading updates) as well as Microsoft NetMeeting and other video conferencing programs.

when ICS is enabled in the computer it also act as a DHCP,DNS,GATEWAY for the clients.The connection to the Internet is shared to other computers on the local area network (LAN). The network adapter that is connected to the LAN is configured with a static IP address of 192.168.0.1 and a subnet mask of 255.255.255.0 ICS can only be used in workgroup envirenment.

How to use Internet Connection Sharing

To use Internet Connection Sharing to share your Internet connection, the host computer must have one network adapter that is configured to connect to the internal network, and one network adapter or modem that is configured to connect to the Internet.

On the host computer

On the host computer, follow these steps to share the Internet connection:

• Log on to the host computer as Administrator or as Owner.

• Click Start, and then click Control Panel.

• Click Network and Internet Connections.

• Click Network Connections.

• Right-click the connection that you use to connect to the Internet. For example, if you connect to the Internet by using a modem, right-click the connection that you want under Dial-up.

• Click Properties.

• Click the Advanced tab.

• Under Internet Connection Sharing, select the Allow other network users to connect through this computer's Internet connection check box.

• If you are sharing a dial-up Internet connection, select the Establish a dial-up connection whenever a computer on my network attempts to access the Internet check box if you want to permit your computer to automatically connect to the Internet.

• Click OK.
  

You receive the following message:

When Internet Connection Sharing is enabled, your LAN adapter will be set to use IPaddress 192.168.0.1. Your computer may lose connectivity with other computers onyour network. If these other computers have static IP addresses, it is a good idea to set themto obtain their IP addresses automatically. Are you sure you want to enable InternetConnection Sharing?

• Click Yes.

system recovery (safe mode)

what is safe mode

when running in safe mode only the minimum required drivers are loading.this includes following.

• Vga with minimum drivers
• Floppy,harddisk and cdrom controller drivers
• Keyboard and mouse drivers

when run on the safe mode only the minimum required drivers to start the computer would be loaded in the boot up process.there for is possible to boot in the safe mode and remove any problematic hardware or its driver prevents the system from starting.

Getting to a Recovery Menu

Instead WinXP uses the combination of Safe Mode and System Recovery to effect repair of your WinXP installation. You also can try the "Last Known Good Configuration" boot option to try to restore your Windows XP system to a workable state if critical system files are not damaged.

To enter the location where these options are available restart your computer then press F8 right after the BIOS message disappears and again after selecting the operating system. You should see these below options.

• Safe Mode
• Last Known Good Configuration
• Start Windows Normally

Selecting these options will do the following:

• Safe Mode

takes you to a stripped-down version of Windows where only the most basic of Windows functions are available to help you troubleshoot your problem. You can choose System Restore in Safe Mode.

• Last Known Good Configuration
  

when changes made to a system during a session they are added to a registry setting called default configuration.these newly added settings to the default configuration will be added to a another register setting called Last Known Good Configuration.in instance or just after a restart and logon boot both default and Last Known Good Configuration are equal.

• Start Windows Normally
  

will load Windows in the regular fashion. If you were having problems last time you attempted to load Windows this option may not work.

system recover (ntldr missing)

The Windows XP CDs has a tool called the Recovery Console which can be used to repair errors that prevent Windows XP from starting using the command line.

• Insert the Windows CD and start the computer.
• When the Welcome to Setup screen appears, press R.
• Type a number corresponding to the Windows installation you wish to repair (this means windows partition,usually 1) and press Enter.
• When prompted, type the administrator password and press Enter.if there is no password leave it blank and press Enter
  
• From the command prompt, copy NTLDR and NTDETECT.COM from the i386 folder of the CD to the root folder of the hard drive. In the example commands given below, C: is the hard drive and D: is the CD-ROM drive. You will need to change the drive letters if appropriate:
  COPY D:\I386\NTLDR C:\
  COPY D:\I386\NTDETECT.COM C:\
• Remove the Windows XP CD from the drive and restart the computer.

Your ntldr missing problem will be solved

bootup process of windows

the process which happens from the time the computer is switch on to the time user logon is called as bootup process.

steps of bootup process

• preboot sequence
• boot sequence
• kernal load
• kernal initialization
• logon

preboot sequence divided into 3 steps

• post (power on self test)
• MBR (master boot record loading)
• nt loader (ntldr loading)
  

print devices (printers)

the print device is a hardware device that is used to take the hard copy of the document.

local printer

when the print device is physically attached to computer it becomes a local printer for the particular computer.

network printer

a shared print device which could be accessed by the client of a network is called as a network printer.

print server

a computer which is physically attached with a print device and also dedicated to control print related activities.

requirement of a print server

• higher harddisk capacity
• higher memory capacity

print drivers

a software interface between the print device and the operating system called as print drivers.

print spooling

in windows when a print job is added to the print que .its automatically and temporarily saved to the harddisk.this is calling spooling.

account lockout policy

an account threshold / reset account lockout counter after the number of invalid logon attempts allowed before and account is lockout indicated here.the time duration that an account is kept logged and account logon counter reset 1 and acount is locked out.

password policy

password policy is a set of rules designed to enhance computer security by encouraging users to employ strong passwords and use them properly. A password policy is often part of an organization's official regulations and may be taught as part of security awareness training. The password policy may either be advisory or mandated by technical means.

enforce password history

the number here indicate no of passwords which are that kept in the history. when a password is added to the history page it cannot be reassign until it released.

maximum password age

the no of days that the password can be kept at maximum indicated here. if a password is not changed within this duration its expired.

minimum password age

this means the no of days that a password must be kept before changing.

minimum password length

With this policy setting, you can assign a minimum number of characters for account passwords. The number can be anything from 0 to 14. It is generally recommended that passwords be a minimum of 7 or 8 characters to make them sufficiently secure.

maximum password length

this means the maximum characters you can put in for a password.
the maximum password length is 128 characters

password must meet complexity requirement

when this option is enabled the password must be consisted with lower and uppercase letters and numbers or alphabets,numbers and symbols.

understanding security policy

security policy is a definition of what it means to be secure for a system organization or other entity. For an organization, it addresses the constraints on behaviour of its members as well as constraints imposed on adversaries by mechanisms such as doors, locks, keys and walls. For systems, the security policy addresses constraints on functions and flow among them, constraints on access by external systems and adversaries including programs and access to data by people.

what is user account

A user account is a profile that defines user rights, customizations and settings. By utilizing user accounts on computers with more then one user, each user is able to specify and retain their personal environments.

user accounts also divided into 2 ways

• Local user accounts
• Domain user accounts

whai is user profile

a user profile is a record of user-specific data that define the user's working environment. The record can include display settings, application settings, and network connections. What the user sees on his or her computer screen, as well as what files, applications and directories they have access to, is determined by how the network administrator has set up the user's profile.

preboot sequence

During startup, a Windows Server 2003-based computer initializes the boot portion of the hard disk and the
preboot sequence begins. This sequence consists of four steps

• the computer runs power-on self test (POST) process to determine the amount of physical memory

• The hardware components are present

• If the computer has a Plug and Play (BIOS), enumeration and configuration of hardware devices occurs

• The computer BIOS locates the boot device and loads and runs the master boot record (MBR)

administrator privileges

you must have administrator privileges to do the following things.

• install network components
• client for Microsoft networks
• file and printer sharing in Microsoft networks
• (TCP/IP) internet protocol
  

benefit of NTFS partitions

NTFS is the recommended file system for Windows XP and provides a number of benefits in terms of functionality, security, stability, availability, reliability, and performance.

NTFS supports for

• file permissions & folder permissions
• supports maximum file capacity
• supports encryption
• supports compressions
• supports disk quota