Some children seem to live in a world all their own. They appear distant and closed-in, avoiding eye contact and shying away from their parents' hugs. They may exhibit strange behaviors, like flapping their arms or obsessively lining up their toys. They are among the approximately 1.5 million children in America who have autism -- a condition that interferes with a child's ability to communicate and interact socially.

Autism has up to now been very difficult to decipher. Scientists still don't fully understand the mystery that lies deep in the brains of children with autism. Although researchers have uncovered clues to what causes the condition, they have not yet discovered a way to prevent or cure autism.

What is concerning to many scientists is that autism appears to be on the rise. Today, one out of every 150 American children has the condition, according to the Centers for Disease Control and Prevention (CDC). Since the 1980s and early 1990s, the rate of autism has increased by approximately 10 to 17 percent annually. Doctors don't know whether this apparent increase is the result of some environmental factor -- such as greater exposure to toxic chemicals -- or simply that children are being diagnosed more effectively than they were two decades ago.

Autism is part of a cluster of conditions called autism spectrum disorders (ASDs), or known by the broader term, pervasive developmental disorders (PDDs). All of these conditions share similar symptoms. Although autism can affect children of any race and ethnicity, it is four times more common in boys than in girls.

Autism can range from mild to severe, but most children with the condition have difficulty in these three areas:

Communication - Children with autism have trouble with both verbal and nonverbal communication. They may avoid making eye contact or smiling, and may not understand the meaning of a smile, wink or wave. About 40 percent of children with autism don't speak at all. Another 25 percent start talking at between 12 and 18 months, but then rapidly lose their language ability. Some children with autism have difficulty forming words into sentences, or repeat exactly what they hear -- a condition called echolalia. Because they can't communicate what they want, sometimes autistic children scream or cry out of frustration.

Social interaction - Children with autism have difficulty relating to other people, in part because they can't understand other people's feelings and social cues. As a result, they can appear distant or aloof. They may shy away from physical or emotional contact, avoiding hugs and eye contact. Because autism affects the senses, some everyday sounds or smells may be unbearable to autistic children. They may cover their ears and scream when the phone rings, or gag from the smell of a peach. Or they may be less sensitive to pain than other children, and not feel a thing when they get a cut or bruise.

Repetitive behaviors - Autistic children often repeat the same behaviors (called stereotyped behaviors, or stereotypy) over and over, including waving their arms, banging their head against a wall, repeating the same words, or obsessively lining up toys, books or other objects. Repetition is a theme throughout an autistic child's life. Any change to their daily routine -- even something as simple as cutting a sandwich straight across rather than on a diagonal -- can lead to a meltdown.

The symptoms of autism can vary dramatically from child to child. While one child may be entirely unable to communicate, another may be able to recite entire Shakespearian plays. One child may be unable to add 3 + 4, another may be able to perform advanced calculus functions.

In addition to autism, four other conditions fall under the header of ASDs

· Asperger syndrome - Children with this condition have some symptoms of autism, including poor social skills and a lack of empathy, but they have age-appropriate language skills and a normal or high IQ.

· Rett syndrome - This condition affects only 1 out of every 10,000 to 15,000 children, the vast majority of them girls. Those with Rett syndrome shy away from social contact. They may wring their hands and be unable to control the movement of their feet.

· Childhood Disintegrative Disorder (CDD) - This rare disorder affects only about two out of every 100,000 children with ASDs, most of them male. Children with CDD will develop normally until about age 3 or 4, then will suddenly and dramatically lose their motor, language and social skills.

· Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS) - This condition shares some of the same symptoms with autism (communication and social delays), but does not meet the full criteria for diagnosis.

Autism is much more common in people with certain genetic, chromosomal, and metabolic disorders, such as fragile X syndrome (an inherited form of mental retardation whose name refers to a damaged and fragile-looking X chromosome), phenylketonuria (an inherited condition in which the body lacks the enzyme needed to process the amino acid phenylalanine, leading to mental retardation) and tuberous sclerosis (a rare genetic disorder that causes benign tumors to grow throughout the body and brain). Epileptic seizures, mental retardation and vision and/or hearing loss are also common in children who have autism.

Next, we'll look at some of the potential causes of autism.


Theory of Mind

In 1995, Dr. Simon Baron-Cohen of Cambridge University proposed a new theory about autism. He suggested that many individuals with autism suffer from "mindblindness" -- that is, they are unable to understand that other people have their own unique thoughts and emotions. It is this inability to empathize and relate to differences in others' way of thinking that results in the communication and social difficulties that people with autism exp erience, according to Dr. Baron-Cohen.

Autism Symptoms

Within the first few months of their baby's life, the parents of an autistic child may begin to feel that something is not quite right. They may notice that their child, who once seemed normal in every way, is acting strangely, refusing to make eye contact, point to toys, or speak.

Even though the signs may appear before age two, most children aren't diagnosed with autism until age four or five, according to the CDC. Part of the reason for this delay is that the symptoms of autism can look much like those of other conditions, which is why autism screening is a multi-step process involving several different health and mental health Professionals.

The first step to diagnosing autism begins with a developmental test administered by the child's pediatrician. If this test suggests an ASD, the next step is to bring in a team of experts, which may include a psychologist, neurologist, child psychiatrist, speech therapist, occupational therapist, physical therapist, and possibly other professionals. These doctors will evaluate the child for neurologic or genetic problems, as well as for cognitive and language skills. Evaluation may include observations, parent interviews, patient histories, speech and language assessments and psychological tests.

Screening tests for autism include:

· The Autism Diagnostic Observation Schedule (ADOS-G): An observational test used to identify delayed social and communication behaviors.

· The Autism Diagnosis Interview-Revised (ADI-R): An interview that assesses the child's communication and social skills.

· Childhood Autism Rating Scale (CARS): An observational test to determine autism severity that uses a 15-point scale to evaluate a child's verbal communication abilities, listening skills, body use, and social relationships.

· The Autism Screening Questionnaire: A 40-question scale used in children four and older to evaluate social and communication abilities

According to the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), children with autism meet at least six of the following criteria:

· Social impairments:

o Does not properly use nonverbal behaviors such as gestures and facial expressions

o Fails to develop age-appropriate peer relationships

o Does not spontaneously share objects or interests with other

o Lacks social or emotional reciprocity

· Communication impairments:

o Is slow to speak

o Has difficulty sustaining a conversation

o Repeatedly uses the same language

o Does not engage in age-appropriate make-believe or socially imitative play

· Repetitive behaviors:

o Is intensely preoccupied with one or more interests

o Is inflexible and unwilling to change set routines

o Repeats motions or mannerisms (such as waving arms, flapping, or twisting)

o Is preoccupied with parts of objects

Next, we'll look at conventional treatments for autism.

Discovering Autism

Although it may seem as though autism emerged only recently, scientists believe that children exhibited its behaviors as early as the 18th century. Autism wasn't formally recognized as a unique condition until 1943, when Dr. Leo Kanner of the Johns Hopkins Hospital studied 11 children with severe language and social problems, and published the first real description of autism. At around the same time, Dr. Hans Asperger of Germany described the syndrome that now bears his name based on his research with 400 children.

Helping Children with Autism

Because there are no real cures for autism, parents often turn to complementary and alternative therapies for their children. Although some parents have had success with these methods, none is scientifically proven to treat autism.

Vitamin and mineral supplements - Dietary interventions stem from the belief that food allergies or vitamin and mineral deficiencies can trigger autism. Some parents give their children B Vitamin supplements (B vitamins create enzymes needed by the brain) or magnesium, although research has not proven their effectiveness.

Special diets - Some research suggests that children with autism may have trouble digesting proteins such as gluten-- found in the seeds of wheat, oat, rye, and barley plants, and casein -- found in dairy products. Many children with autism are on gluten- or casein-free diets.

Secretin - Some research found that this hormone, which aids in digestion, improved communication and social skills in autistic children. However, research by the National Institute of Child Health and Human Development found no real improvements with this treatment compared to placebo.

Chelation therapy - Following the school of thought that autism may be caused by exposure to environmental toxins, such as mercury and other heavy metals, chelation uses a chemical agent to bind to and remove these metals from the body. Although a number of parents have claimed that this treatment has improved their children's symptoms, chelation hasn't been scientifically proven, and the substances used in the treatment can themselves be toxic and cause allergic reactions in some children.

Facilitated communication - In this type of therapy, a facilitator holds the hand, arm or shoulder of a autistic child and helps him type on a computer keyboard to assist in communication. This technique is not considered a valid treatment for autism, and it is very controversial, because some people claim that the facilitator is doing the communicating rather than the child.

In the next section, we'll examine some common myths about autism.

Autism Awareness

From the 1950s until the 1980s, a prevailing theory about the cause of autism was that it stemmed from bad parenting -- the so-called "refrigerator mother theory" (meaning the mother is emotionally cold) put forth by child psychologist Bruno Bettelheim. Today, we know this is untrue. Autistic children aren't poorly raised -- they are born with an inherited susceptibility to the condition.

Autistic children also are not badly behaved -- their temper tantrums and other unusual behaviors stem from their frustration in being unable to effectively communicate and interact socially. They are not dumb, either; in fact, some autistic children are extremely gifted in one or more areas

A common misconception is that people with autism are slow or mentally retarded. In fact, a small percentage of people with ASDs are remarkably gifted. Consider Kim Peek, the inspiration for Dustin Hoffman's character, Raymond Babbitt, in the 1988 film, "Rain Man." Peek has read more than 7,000 books, and can recall with photographic accuracy more than 80 percent of their contents. Given a person's date of birth, he can immediately produce the day of the week on which the person was born. London-born author and math whiz Daniel Tammet can recite the number pi to more than 20,000 digits, and fluently speaks 10 languages. He's even invented his own language, Manti.

There are also people who were diagnosed with autism as a child but may actually have Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS). Dr. Temple Grandin, a professor of Animal Science at Colorado State University, is a famous example of a person who overcame autism and became highly successful. Dr. Grandin has designed livestock handling facilities used throughout the world, written four books -- including a New York Times bestseller -- and appeared on numerous TV and radio shows.

Brain Damaging Habits!!!!

1. Over Eating.

2. Avoid Breakfast.

3. Smoking.

4. High sugar Consumption.

5. Air Pollution.

6. Sleep Deprivation.

7. Head Covered while sleeping.

8. Working your brain during illness.

9. Lacking in simulating thoughts.

10. Talking Rarely.

So please avoid these Habits and live long Life..

Sardhar Jokes

A Sardar Story

One rainy day a Sardar was traveling by his new FERRARI car. He was Not

a very good driver and so did not have complete control on it.

Mike Tyson was also riding his bike on the same road. At a speed breaker

Sardar's car came in contact with Tyson's bike.

Tyson got very angry. He dragged sardar out of the car and threw him a

Few yards away from the car.

Tyson then drew a small circle around sardar and shouted "Hey!! It's not

Easy for you to damage my bike and get away. Now I will be thrashing

Your car. You should stay inside this circle and watch me smash your

Car. If you come out of the circle, I will kill you immediately" .

Then tyson turned towards the car and he smashed its side indicators.

Then he looked at sardar. Sardar looked at Tyson's sarcastically.

Tyson's anger grew and he smashed the window panes and then again looked

At sardar. Sardar grinned at Tyson.

Tyson was confused. Tyson could now not at all control his anger and he

Broke the side doors and tore away the seats of the car. Then he again

Looked at Sardar. Sardar was laughing so hard that he could hardly


This time Tyson came to Sardar and he told "oh! What is this? I am

Spoiling your expensive car and you are so happy about it?"

Sardar replied "Every time you turned towards the car I was out of the

circle And you did not notice it!!

Sardar in Interview

Interviewer tell me opposite of

sardar bad

Int: come
sdr: go


sdr: pichli

Int: shitup
sdr: keep talking

Int: get out
sdr: come in

Int : Oh my God
sdr : Oh my devil

Int : u r rejected
sdr : I m selected

Int : !!!!


Sardar as Army Major

Soldier: "Sir, we are surrounded by the enemies",

SARDAR Major: "Excellent ! We can now attack them in any direction" !.

Sardar in Exam Room

In a maths Exam every one was writing but one sardar was continuously Dancing!!


Because someone told him that there is marks for every step....


In Exchange 2000/2003, what is the Active Directory Cleanup Wizard and what is it good for?

The Active Directory Account Cleanup Wizard is a utility designed to merge duplicate Microsoft Windows NT accounts that are created when multiple directories are migrated or upgraded to Active Directory. The Active Directory Account Cleanup Wizard searches Active Directory for duplicate Windows NT accounts, and then suggests merge operations that eliminate the duplicates. You can also verify the individual merge operations. Finally, the wizard merges various account types, their attributes, and their properties into a single user account. Removing duplicate accounts in Windows 2000 Active Directory can help improve performance of your Exchange 2000 servers.

The Active Directory Account Cleanup Wizard allows you to:

  • Identify duplicate objects to be merged. You can have the wizard search Active Directory for possible duplicate Windows NT accounts, or you can manually select the duplicate accounts that you want to merge.

  • Review and modify merge operations that the wizard has selected to perform before you merge the duplicate accounts.

  • Export and import lists of accounts. This functionality gives you the flexibility to export a list of merge operations (pairs of duplicate accounts) into a .CSV file so you can import them back to the Active Directory Account Cleanup Wizard for further review. Then at a later time, you can run the merge process.

Creating and Editing GPOs

A Group Policy object (GPO) is a collection of policy settings that can be applied to a given set of users and/or computers. The process of applying a GPO to a set of users and/or computers is known as “scoping the GPO”, which is described later in this white paper.

With GPMC, you can create GPOs using any of the following methods:

**Right-click any domain or OU and choose Create and Link. This option simultaneously creates a new GPO and links that GPO to that domain or OU.

**Right-click the Group Policy Objects node in any domain in GPMC and click New. This will create a new unlinked GPO.

**Using a script. For example, GPMC includes a sample script called CreateGPO.wsf that can be run from the command line to create a new GPO.

**Using any of the methods for copying GPOs. Copy operations are described later in this white paper in the section on GPO operations.

When you create a new GPO, it initially has no settings defined. To edit the settings in a GPO, use Group Policy Object Editor (known previously as the Group Policy snap-in or GPedit). You can open Group Policy Object Editor by right clicking a GPO in GPMC and selecting Edit.

Active Directry - Networking Questions and Answers

Forest trust

A trust that must be explicitly created by a systems administrator between two forest root domains. This trust allows all domains in one forest to transitively trust all domains in another forest. A forest trust is not transitive across three or more forests. The trust is transitive between two forests only and can be one-way or two-way. See also shortcut trust; external trust; realm trust.

Forward lookup

In Domain Name System (DNS), a query process in which the friendly DNS domain name of a host computer is searched to find its Internet Protocol (IP) address.

Global catalog

A domain controller that contains a partial replica of every domain in Active Directory. A global catalog holds a replica of every object in Active Directory, but with a limited number of each object’s attributes. The global catalog stores those attributes most frequently used in search operations (such as a user’s first and last names) and those attributes required to locate a full replica of the object. The Active Directory replication system builds the global catalog automatically. The attributes replicated into the global catalog include a base set defined by Microsoft. Administrators

can specify additional properties to meet the needs of their installation.

Global catalog server

A domain controller that holds a copy of the global catalog for the forest.

Global group

A security or distribution group that can contain users, groups, and computers from its own domain as members. Global security groups can be granted rights and permissions for resources in any domain in the forest. See also local group; group.

Globally unique identifier (GUID)

A 128-bit number that is guaranteed to be unique. GUIDs are assigned to objects when the objects are created. The GUID never changes, even if you move or rename the object. Applications can store the GUID of an object and use the GUID to retrieve that object regardless of its currentdistinguished name.

GPO See Group Policy Object (GPO).


A command-line tool that enables you to create and display a Resultant Set of Policy (RSoP) query on the command line. In addition, Gpresult provides general information about the operating system, user, and computer.


In Microsoft Windows Server 2003 and Microsoft Windows XP Professional, a command-line tool that enables you to refresh policy immediately. Gpupdate replaces the secedit.exe/refreshpolicy command used for refreshing Group

Policy Objects (GPOs) in Microsoft Windows 2000.

Snake Wine.... What a drink...!!

Snake wine (rÆ°á"£u rắn in Vietnamese) is an alcoholic beverage that includes a whole venomous snake in the bottle. It originated in Vietnam and can be found around Southeast Asia. The snakes, preferably venomous ones, are usually not preserved for their meat. They are preserved to have the snake poison dissolved in the liquor. However, because snake venom is protein-based, they are unfolded and therefore inactivated due to the influence of the denaturing effects of ethanol.

A large venomous snake can be placed into a glass jar of rice wine, often with many smaller snakes, turtles, insects, or birds, and left to steep for many months. The wine is drunk as a restorative in small shots or cups

Body fluids of snake are mixed into wine and consumed immediately in the form of a shot. Snake blood wine is prepared by slicing a snake along its belly and draining its blood into a mixing vat with rice wine or grain alcohol. Snake bile wine is done through a similar method by using the contents of the gall bladder. Snake meat, liver, and skin can be prepared to accompany the drinks

Problem in your Mails - Here some Resolution...

Problem - I can't open some of my email attachments

* Opened in wrong application program
* Created in a different coding scheme
* After double clicking on the attachment, drop down menu appears asking what program to use to open the attachment.

Solution -

* Try opening the attachment as a different application. To do this, rename the attachment using the appropriate ending (doc, ppt, jpg, etc.)
* Choose Notepad or WordPad from the list on the drop down menu and see if one of those programs will open your attachment.
* Ask sender to note in the body of the email what application was used.
* If all else fails, ask sender to include attached information in body of email message.

Problem - My Email won't work

* Email program has not been configured to communicate with network and/or modem
* Using the wrong e-mail program - set up in another program
* Using wrong user name or password (both are case sensitive).
* Message is in outbox and cannot be sent because address is incorrect.

Solution -

* Make sure email program is configured correctly
* Make sure you are in the email program that was set up to receive and send your email.
* Make sure user name, password, and/or the correct case (upper or lower) has been used.
* Remove any messages that are still in your out box after email has been sent.

Signatures and Personalities

The various types of Signatures you come across & the attitude of a person are listed below:

These persons are very confident and are good personalities. They are a little bit selfish but believe in "Happiness of human life"

These persons are considered to be Romantic, can easily change their fiancées as if they change their clothes. They prefer beauty in other persons & they themselves try to look beautiful. They easily attract others.

These persons are more inclined towards classical arts, simple & are very cool. If you loose faith with them, then these persons will never look back at you. Hence its always better to be careful with these people.

These persons enjoy their life in their own way, never pay attention to others views. These are considered to be good natured but are selfish too.

These persons try to be very smart, hide each & every matter, never say anything in straight forward manner, never pay attention to the other person of what he is talking of.

These persons are considered to be intelligent but never think. These people change their ideas & views as fast as the wind changes its direction of flow. They never think whether that particular thing is right or wrong.
You can win them just by flattering them.

These persons are very kind to us, have a good heart, selfless, are ready to sacrifice their life for the sake of their near & dear. But these seem to think a lot and may get angry very soon.

These persons are very kind hearted, can adjust themselves to any environment & to the person they are talking. These persons are very firm on their views & posses a lot of will power.

Mind Blowing Facts 5

126. Queen Elizabeth I regarded herself as a paragon of cleanliness. She declared that she bathed once every three months, whether she needed it or not

127. Slugs have 4 noses.

128. Owls are the only birds who can see the colour blue.

129. Your tongue is the only muscle in your body that is attached at only one end

130. More than 1,000 different languages are spoken on the continent of Africa.

131. There was once an undersea post office in the Bahamas.

132. Abraham Lincoln's mother died when she drank the milk of a cow that grazed on poisonous snakeroot

133. After the death of Albert Einstein his brain was removed by a pathologist and put in a jar for future study.

134. Penguins are not found in the North Pole

135. A dentist invented the Electric Chair.

136. A whip makes a cracking sound because its tip moves faster than the speed of sound

137. Alexander Graham Bell's wife and mother were both deaf

138. Cockroaches break wind every 15 minutes.

139. Fish scales are an ingredient in most lipsticks

140. Canada" is an Indian word meaning "Big Village".

141. 259200 people die every day.

142. 11% of the world is left-handed

143. 1.7 litres of saliva is produced each day

144. The worlds oldest piece of chewing gum is 9000 years old!

145. The largest beetle in the Americas is the Hercules beetle, which can be 4 to 6 inches in length. That's bigger than your hand!

146. A full-grown male mountain lion may be 9 feet long, including his tail!

147. There are two kinds of radio stations: AM and FM. That's why there are two dials on your radio. AM is used mostly for stations that specialize in talking, such as Christian stations that have Bible stories and sermons; sports stations that broadcast live baseball and football games; and stations that specialize in news programs and "talk shows," where listeners call the station and discuss various topics. FM is used mostly for stations that specialize in music.

148. The average lead pencil can draw a line that is almost 35 miles long or you can write almost 50,000 words in English with just one pencil

149. The Wright Brothers invented one of the first airplanes. It was called the Kitty Hawk.

150. The worst industrial disaster in India, occurred in 1984 in Bhopal the capital of Madhya Pradesh. A deadly chemical, methly isocyanate leaked out of the Union Carbide factory killing more than 2500 and leaving thousands sick. In fact the effects of this gas tragedy is being felt even today.

151. Mars is nicknamed the "Red Planet," because it looks reddish in the night sky. Mars has 2 moons.

152. Venus is nicknamed the "Jewel of the Sky." Because of the greenhouse effect, it is hotter than Mercury, even though it's not as close to the sun. Venus does not have a moon but it does have clouds of sulfuric acid! If you're gonna visit Venus, pack your gas mask!

153. Tens of thousands of participants come from all over the world, fight in a harmless battle where more than one hundred metric tons of over-ripe tomatoes are thrown in the streets.

Using NAT to connect Windows 2003 to the Internet

Windows 2003 offers a feature called NAT, which you can use to achieve much of the same
functionality that you can with ISA Server when connecting your network to the Internet. Here's an introduction to NAT and how your network can benefit from it.

Do you use Microsoft’s Proxy Server or ISA Server to connect your network to the Internet? If so, you may be surprised to find out that Windows 2003 offers a service called Network Address Translation (NAT) that you can use to achieve much of the same functionality as you can from these products. Here's an introduction to NAT and how your network can benefit from it.

What is NAT and how does it work?

NAT's purpose is to hide the IP addresses that are in use on your internal network. Not only is this functionality good from a security standpoint, but it also allows you to make up your own IP addresses for your local network without the fear of duplicating actual Internet addresses.

Okay, so NAT sounds wonderful, but you may be wondering how it works. To understand what really goes on, let’s look at an example of a network configuration. Imagine that a network card connected to the Internet uses an IP address of, while the network card that’s connected to the local network has an IP address of Let’s also assume that NAT is running on the server that’s connected to the Internet.

Now, suppose that a PC with the IP address needs to access a Web site. As usual, the outbound packet’s first stop would be the server that’s connected to the Internet; however, NAT prevents the packet from being sent out. Instead, NAT maintains a database of outbound communications. The database is updated to reflect the internal IP address of the PC sending the packet and other information, such as the destination address. NAT then adds a random port number to the database entry. For example, NAT might assign port 83 to the PC.

At this point, NAT sends the packet to the destination. But instead of using the address, the packet now has the address (the address of the server). Since port 80 is typically used for HTTP -based communications, the packet is sent out on port 80. The packet, however, contains instructions that the remote Web server should reply through the random port number that NAT has assigned to the PC. In the case of my example, this would be port 83.

When NAT receives an inbound communication, it looks at the type of information that’s been received and what port number the communication arrived through. In this case, if NAT received HTTP-based communications at port 83, it would look in its database and realize that port 83 was associated with PC number It would then forward the packet to this PC.

The big exception to this method is in situations where the PC that’s connected to the Internet contains multiple registered IP addresses. In such a case, no port translations are necessary.

The dark side of NAT

As great as NAT sounds, there’s an issue you need to be aware of. NAT isn’t designed as a total replacement for ISA Server. As you may know, ISA Server contains some functionality that simply doesn’t exist in a NAT environment.

One of these features is a proxy cache. ISA Server maintains an active cache of all recently accessed Web pages. This allows ISA Server to save bandwidth and increase client response speed by accessing pages from the cache instead of off the Internet when possible.

The biggest thing that’s missing from NAT, though, is a full-featured packet filter and firewall. ISA Server lets you block any ports that aren ’t essential to your organization. This capability is important because hackers can use these obscure ports to gain access to your network. Likewise, ISA Server also protects you against hackers by allowing you to block any protocols that aren ’t frequently used. NAT lacks this capability. Basically, this means that NAT provides a useful service, but don’t expect it to take the place of a full-featured firewall.

If you do use an external firewall, remember that while you ’re safe when blocking unused protocols, blocking unused ports may cause NAT to malfunction since it depends on these ports for inbound HTTP communications.

Installing NAT

The process of installing NAT is relatively simple. Open the Routing And Remote Access console by clicking the Start button and selecting Administrative Tools | Routing And Remote Access. When the console opens, navigate through the tree on the left side of the screen to Routing And Remote Access | your server | IP Routing | General.

Now, right-click the General object and select the New Routing Protocol command from the resulting context menu. When you do, the New Routing Protocol dialog box will open. This dialog box contains a list of various routing protocols. Select Network Address Translation (NAT) from the list and click OK. Network Address Translation now shows up as an object in the tree beneath IP Routing.

Configuring NAT

You can configure a number of parameters for NAT. Right-click Network Address Translation in the list and select the Properties command from the resulting context menu. You’ll then see the Network Address Translation (NAT) Properties sheet.

The default tab on this properties sheet is the General tab. This tab allows you to select the level of logging that takes place due to NAT ’s actions. The default option is to log errors only, but you can elect to log errors and warnings, log the maximum amount of information, or disable event logging for NAT altogether.

The next tab, Translation, lets you set the timeout period for TCP and UDP mappings. By default, the timeout is 1440 minutes for TCP mappings and one minute for UDP mappings. Generally, these settings will work fine for most networks. If, however, you have an application that requires longer mapping times, or if your network is extremely slow, you may need to bump these values up, especially when it comes to the UDP mappings.

The next tab you’ll encounter, Address Assignment, is optional. It allows you to implement DHCP through NAT, even if you aren’t running a separate DHCP service. If you enable this service, then NAT—not the normal DHCP server— assigns IP addresses to clients on the local network. The configuration options on this tab are pretty self-explanatory.

The final tab is Name Resolution. This tab provides an easy way to enable DNS services for name resolutions. Allyou have to do to enable this feature is select a check box. If you don ’t have your own DNS server, you can even use this tab to make NAT connect to the Internet when it needs to resolve an address.

Configuring the NAT interfaces

So far, I ’ve shown you how to install and configure NAT; however, you still have to configure the NAT interface—the mechanism by which NAT knows which networks to bridge. There are a lot of ways to set up NAT interfaces. Since this article is all about linking a private network to the Internet, I’ll walk you through the configuration process as though this is what you were trying to accomplish.

Begin by opening the Routing And Remote Access console and navigating through the console tree to Routing And Remote Access | your server | IP Routing | Network Address Translation. Next, right-click Network Address Translation and select the New Interface command from the resulting context menu. At this point, you’ll see a dialog box that lists all of the existing connections on the server. Select the connection you want to work with and click OK.

Now you’ll see a dialog box that asks if the connection is a private interface that’s connected to a private network, or if it's a public interface connected to the Internet. If you ’re configuring a private interface, simply make the appropriate selection and click OK. If you ’re working with a public interface, though, there ’s a bit more configuration to do.

If you ’re configuring a public interface, the next step is to select the Address Pool tab. This tab lets you input the IP addresses that your ISP has assigned to you. NAT will translate the addresses used by your private network into the legitimate addresses that you insert into this area.

Finally, switch to the Special Ports tab. This tab gives you the chance to tell NAT about any special port -related needs that your network might have so that NAT doesn’t try to remap the port.

Who needs ISA Server?

You can use Windows Server 2003's built-in NAT to achieve some of Proxy Server’s and ISA Server's functionality. If you decide to implement NAT, remember that NAT doesn’t offer the IP packet-filtering capabilities offered by ISA Server. It’s important to use a firewall or Windows 2003’s packet-filtering capabilities in conjunction with NAT.