Following these words are some of my shooting experience and feelings, while not “professional”, but would like to give some love nature, photography-loving friends some insights.

1, according to the behavior of insects to determine time of filming. The morning sun just rose up, whether from the perspective of photography, or the habits of some insects are very good perspective of shooting time.

The gap through the tent to see the sky is already some light,Dell Vostro 1000 battery
I got up and picked up the camera, slowly pull out of the tent zipper drill, a few came in last night was a small light to attract moths fly out followed suit, they fly low, along the direction of their flight, I saw the sun above the horizon just jumped out. Thick meadow dotted with numerous wild flowers, seemingly calm, in fact, full of life, yes, this is what we dream of the best shooting time. At this time the temperature is still very low in the grass, insects are almost stationary, they have to wait after the sun rises fully to absorb the heat, the day’s activities will begin. This undoubtedly provided us with excellent photo opportunities, as long as you find them, could easily compose and shoot.

Through the night temperature, dew grass into the world, they are scattered all over the place: a wide or narrow leaves, delicate flowers, the rules of the spider’s web, as well as butterfly wings.Dell Inspiron Mini 9 Replacement battery Weak light may increase the exposure time accordingly, you should try to choose the most stable shooting position, the shutter speed is less than 1 / 20 seconds is recommended tripod shooting. The spread of the sun, like the curtain was slowly opened, when the soft and beautiful “Light” shines on the stage when the insects can not wait to start show.

A small gray moth looks down the slender grass climb the open area, there is no weed block, the sun shines on it nice and warm to him. Inadvertently, presented in front of me was a perfect picture of the nature described.

2, according to the habits of the subject,CASIO np-60 camera battery looking for shooting models. Moreover, you should understand some of the relevant knowledge.

People often say, “Splendor flowers”, in fact, like many insects visiting flowers. Various bees, flies, flower beetles, small beetles, etc., they are inseparable from the flower, can not do without this sweet food. If you do not have knowledge of certain insects, and are impossible to start looking for insects, may wish to take note of some flowers. Insects feeding on the flowers when the alert will be reduced some, we can more easily access them. Nettle this beautiful butterfly just keep tooth and nail, even though I shot at close range, it also unaware. Shooting photos of such a large color contrast, try to select the butterfly in the middle of color to the metering.

3, in the filming process, we need a discerning eye, carefully observed.

Many friends have asked me why they do not see so many insects? Indeed, the insect body size is very small, not easy to draw our attention, but also the use of “mimicry” and “protective coloring” to deal with predators, they try to integrate themselves into the surrounding environment, to our finding a greater increase challenges. However, if you are willing to spend more time and patience to find, I believe you have a very good harvest.

Show about a class is good at hiding the insects, they are always quietly lying on the grass, and the limbs stretch as far as possible to enjoy the sun. Mimics their own very self-confident, even if very close,battery for HP Compaq Business Notebook NX6140 as long as you do not touch it, it will not budge. We can devote more time to consider the composition, as far as possible Tettigonioidea long filamentous antennae and extend the limbs are taken complete. Large aperture, we still have a near perfect depth of field, you can clearly see the wings covered with vein-like pattern and that little eyes sparkle.

4, plus a little bit of luck, patience is a prerequisite for successful shooting some of the insects.

Nature photographer, especially shooting the smaller insects, careful patient is essential to find a little bit of luck will bring you surprise. Cicada species is more difficult to shoot, they either indulge in singing the high branches, or on it very far away from you, when suddenly the dense foliage away after a while rattling, almost does not give you the opportunity to shoot This time we need a little luck for help. Hot and quiet afternoon in the mountains, I am a man climbed halfway up the mountain and decided to sit down and a break. Inadvertently, found only in the ancient ginkgo tree trunk lying on the Maemi, which is about 20 centimeters away from my will,EliteBook 2730p battery and have no means of escape. Viewfinder I first look to see a cicada: a pair of stout front foot, abdomen, two mid-summer atmosphere of the tympanic membrane manufacturing sounder, and two pairs of membranous wings and strong – this is simply a masterpiece of the Creator! Shot using a large aperture, so that blur the background out of quartzite, and the cicadas who just simple and elegant harmony of colors, the picture gives a tranquil feeling. After all, luck favored by a minority, more or to test our patience. Of course, this is the fun part of nature photographers. Long-horned bee is a type of patience before they can take to the insects, they are always busy shuttling between the various flowers,EliteBook 2740w battery each flower takes time to stay very short, almost not give me a shot opportunity. I could only watch one guy who wore long tentacles flying in front of me. Fortunately, I found these guys tired to fly on the pine needles would fall a little rest, but the shooting is still difficult, they really do not waste their big eyes, little action as long as I will immediately take off. I had a pair of Dundao low pine needles waiting for the opportunity, did not think the other is nearly 3 hours, okay, the photos you want photographed, but also long-horned bees have a better understanding.

5, there will always insist on return, photography itself is not easy, insect photography even more so.

Mantis in the flowers was a big guy caught the Syrphidae, thirty-two to eat the most part. Game soon attracted to the taste of a group of greedy little fly, they keep flying around the praying mantis,price of HP Compaq Business Notebook nx8220 battery a rush to have the opportunity to enjoy a feast of doing nothing, and even the guy’s mouth fell lick mantis Fresh juice. The face of these nasty invaders, the mighty mantis no way. Large aperture virtual body almost out of mantis, mantis highlights on the eyes and firmly clamped to capture enough prey. The surrounding environment is complex, try to choose the vertical composition make mantis fill the screen, so that subject more clear.

A good photograph should first of Insect Ecology is a vivid picture. We normally see a lot of common insects, in fact, can shoot a good picture. Many people think that good photos, either bloody strangulation scene, or the type is very rare, and I think a picture is vivid ecosystem is essential.

Insects in their little world to complete a short self-serving life course: the pursuit of happiness, or spouse; or resort to force to prepare for hunting; or a big mouth and chewing on delicious food. All of these are happening around us, the real and very common. However, as long as the insect itself, With love, to understand their passion for life, we can use their own cameras to record the insects but usually brilliant, true and no shortage of lively moments, to use your own photos to give insects “personality”!

A little bit about the good insect photography tips: During the shoot, no matter how careful we are, in fact, are more or less disturb the lives of insects. Ants, aphids, animal husbandry, accelerated the pace of panic, a small beetle reduced to less than one fell to the grass, the boat kept shaking larva’s body hung upside down, leafhoppers quickly flash back to the leaves, enough to capture mantis raised, eyes dead death staring at you … … there are some masters of mimicry, camouflage their confidence,Compaq Presario v6000 Battery such as Tettigonioidea or some geometrid moth larvae, even if we close contact, they do not hit them, they would have maintained the original Some attitude, motionless, and you think it afraid of you, you do not disturb it, it is not true, just that they chew the leaves are still shoveling or cleaning the body comfortably, as you come, all this stopped. Therefore, we should bring them to minimize the pressure and panic. I usually approach them carefully, dodging the subject after one or two I would consider giving up photography. In fact, after all, looking in nature we can not have no effect on the ecosystem, it is important that there should be moderate.

First, consumer digital cameras and digital SLR cameras compared to when shooting portraits where there will be several of the more negative, we must be clear.
1. The CCD area is relatively small, shallow depth of field is difficult to get good results.
2. Shutter delay is relatively long, unlike the instant digital SLR is easier to catch the facial expression, is not conducive to catch the beat.
3. The camera does not provide a higher ISO options, or at high ISO,compaq presario v3000 battery
the noise is relatively high to screen the other rough.
However, the use of consumer DC to shoot portraits, but also not a place without incident, there is no advantages.

DC consumer advantages:

First of all, DC in the shot and consumer LCD display can be observed directly the result of preview to the film, brightness distribution at a glance, can enhance the success rate of shooting, will increase the fun of shooting, for starters, more easy to use.
Another consumer generally small size and weight of DC light,HP EliteBook 6930p Replacement battery relatively easy to carry on, go out shooting, especially in crowded places would not like to swagger like the digital SLR, scary, not easy when the photographed was found that the success rate of shooting naturally be increased.
Second, the consumer DC Although there are relatively deep depth of field defects, but from another perspective, in some characters and scenes are clearly needed, or to show the relative relationship of the time people, but will take advantage of.
Finally, the consumer benefits of DC of course, is its relatively low price, the move is over a million compared to the digital SLR is really a lot cheaper!

Beginners when shooting portraits, often complain about their gear, wait for DC to throw away the hands of the consumer in exchange for a digital SLR, shooting to get better and faster operational efficiency. However, the consumer can not make a good DC does not necessarily work, we have described above consumer DC also has its advantages, more emphasis on other Portrait photography is the charm and feel of the characters, but these are not good or bad depends on the equipment, but on the characters and the communication and co-photographer, depending on the time of the shooting situation.

Unless such a dynamic fashion show class performance, due to the harsh environment the stage scene, have to rely on the superior performance of equipment, we ordinary people in the shooting, as long as we feel, lots of pictures,price of ACER Aspire 5732Z battery even with an ordinary consumer DC also can photograph a lot of good photos.

You have set a correct view of it? With the right perspective, the following us to explain some basic knowledge and skills.

One. To maintain the stability of the camera

Many beginners did not agree with this point, no heart, the result pictures are often blurred in the case, keep the stability of the camera is to obtain a necessary condition for a clear picture, photos are not clear, even if you use light on how exquisite, how rigorous composition, obtained only a scrap piece.

Can be used to maintain the stability of the camera tripod, tripod shooting but the lack of flexibility, in addition to night shooting, we are rarely used. To maintain the stability of the camera there are some skills,NIKON en-el5 camera battery first of all, to steady your camera, the other in the do first take a deep breath before pressing the shutter, and then release the shutter until the breath until this method is very useful, can effectively reduce tremor the situation is the auto show in the following photographs, although the lighting is bad, but because of the method used or to maintain a relatively good stability.

Some consumer now has anti-shake function of DC, such as Panasonic FZ10 and the FX5, Canon S1IS, Minolta A1 and other cameras, and their anti-shake performance can help you effectively reduce camera shake.

II. Exposure

Accurate exposure is the most difficult to master photography one of the factors is the key to success photos.

Fortunately, digital cameras with automatic metering functions, and generally very accurate metering, DC, in most cases are able to obtain accurate exposure photographs. However, it is worth noting in some cases, such as the time when the light is relatively strong, we must consider a partial picture may have exposed the phenomenon, because in most cases people affected by the degree of illumination is not uniform, there are always some dark places which is lighter, more general use of the average DC metering method is based on the image brightness of each region the average of the exposure, which is why some beginners photos will appear overexposed because,Dell Inspiron 9400 laptop battery like the picture below is too strong and caused the light of local overexposure of the image.

Encountered such a situation, we can not rather than the principle of less exposure, because even if underexposed pictures in the computer can also make an appropriate adjustment, on the contrary if the photo had been exposed is difficult to save.

Rather not have the exposure control due to the camera’s exposure compensation can be achieved, there are some other features the camera also has a spot metering, spot metering to master the techniques are easier to obtain accurate exposure photos, but Spot is not easy to master the skills , but will also fix overexposed photos of serious or serious the situation due to exposure, where the author suggests that beginners are strong in the face of light, proper adjustment of the negative exposure compensation to avoid overexposure of the situation.

III. Depth of field

Depth of field can blur the background picture of the prominent figures of the main very good, but the digital camera CCD sensor size is too small, usually between 1/2.7 inch to 1/1.7 inches,battery for TOSHIBA PA3399U-1BAS even with large aperture is also difficult to obtain the virtual depth of field . However, we do not forget about the depth of field in addition with the aperture, the camera’s focal length can also affect the depth of field, focal length the more they can get shallow depth of field, if your hand is 10 or 12 times the big zoom DC, then To obtain a good depth of field is not a difficult task, of course, many consumer DC are only 3 times zoom function, then you can select the background taken place relatively open, so people have enough space for the rear, and then with the telephoto-shot digital camera This can also get good results, the following is the king FZ10 telephoto pictures taken, you see, the DC consumer can also get satisfactory results it!

can truly reflect the clarity of the camera and was shooting the real side of things. Often take advantage of macro, we can put some of the plants and flowers look flat Fanfan,

and even have taken a variety of creatures to life. The complete Collection of our digital photography came to talk about macro photography with a digital camera some of the

methods and techniques.
Learn to use the eye when the lens
When we have our camera ready to photograph from the time, do not just see things in the viewfinder as a tool to learn your own eyes,IBM ThinkPad R60 battery the feeling of training with the lens, the

only way we can accurately grasp the shot we want things. Before doing macro photography, we first have to learn is to carefully observe the dedication of a variety of things,

not to rush to press the shutter. The so-called macro, saying that white is very close in a long time to capture the screen, obviously, to capture the images must be the object

of a certain kind of detail. So, as long as we feel that there can be some of the performance of close-ups do not give up. In fact, not difficult to find such things, as long

as it is part of a body with a certain kind of features there is no problem. This feature can be a shape, color, expression, status, etc., so that the macro can be used not

only to the performance of plants and flowers, all things can be.
Equipment requirements
1, the camera or lens with macro capability. In general, the digital camera lens is not replaced, only a few more professional digital camera. Well, for a digital camera can

not replace the lens in terms of which requires the body with macro function, general English letters graphical representation of micro and small flowers. For the digital

camera lens can be replaced in terms of the general requirements with the lens itself has the function of macro photography.
2, the best mode or with the central focus point of side light side light.ACER Aspire 5738G Replacement battery This is because the orientation of the object to be taken less need for accurate metering for

accurate exposure.
3, the camera itself is relatively light or with a tripod. When doing macro shooting as the most likely change because of the virtual hand leaving the screen, so in order to

ensure a clear picture, the best selection of portable digital camera tripod, or trustworthy.
4, the focal length and magnification. The choice of focal length is a very serious issue, but also macro photography problem to be solved first, the choice of focal length and

magnification should be considered together:
Flowers, still life :50-100mm or so more appropriate, magnification 1 / 8 to 1 / 4 can; insects, small animals :100-200mm or so more appropriate magnification in 1 / 4 to 1 /

2, 1 / 1 more good. For the macro lens, the most important thing is the size of the actual working distance and magnification.
5, the aperture need not be great. Do not think that there will be obvious to enlarge the aperture depth of field. In macro shooting, their depth of field will produce very

clear results, it does not necessarily need a large aperture.Dell Inspiron 1420 laptop battery
Shooting a few important details
1, pushed to the wide-angle end of the zoom during filming. This is not targeted at digital cameras with interchangeable lenses is the. And must use the telephoto end of

traditional film camera macro contrast, digital camera macro will need to adjust to the wide-angle zoom, and then select the Macro shooting mode to shoot close objects. Only

then can a more accurate and efficient.
2, note that when shooting light. Let’s talk about the light-bit key usage:
(1) shun light. Also called “positive light” refers to the direction of light projection and filming in the same direction of the light. In this light, the subject even by

light, the scene is not shadows, color saturation, can show the rich color effects. However, the lack of light and dark contrast features, there is no level and dimension. I

personally do not like to use this light, photos as if telling a tale, not vivid.battery for JVC bn-v114
(2) backlighting. Also known as backlighting, light and shoot in the opposite direction, to outline the contours of the brightness of the subject is also known as contour

light. Structured scene under backlight lines prominent, vivid screen, shoot photos and spatial three-dimensional sense. Therefore, the best performance of the backlight in the

dark against the dark background landscape, is an ideal light. We often use it to capture the silhouette, the effect is good.
(3) side light. The direction of light projection is greater than 0 degrees and take direction at less than 90 degree angle to the light, side light under the object, a good

contrast between light and dark, with a three-dimensional, color reproduction is good, rich layers of film grain, while most of the 45-degree The side light is the best,

because it is consistent with the visual habits of the people, is one of the most commonly used light-bit.
(4) top light. Is the subject of light from above. Top light, the scene of the horizontal illuminance is greater than vertical illuminance, the lack of intermediate level,

shoot the scene, the characters seem not angry, is a less than ideal light. But for the old man, old peasant woman black eye socket and other special characters, prominent

cheekbones, very expressive wrinkles Daoke.
(5) low light. Is just rising from the ground or the sun’s rays fall, mainly from the morning and evening. Low-light shoot the scene is very vivid, very angry, and this light

color temperature is low, was the warm red tones, has a special color effects, is an ideal light.
(6) scattered light. Also called false Yin Tianguang line, average illuminance, light and soft, light than the small, small color in the subject no obvious projection. The

light should show a better life quiet, innocent and naive girl children.
3, note that the shooting angle. First of all, photography is the direction of the camera and the subject in the horizontal plane of the relative position of the camera, that

is, we usually say that the front, rear, left, right, or front, back, side. When we started taking pictures when photography is always the first choice point, is to choose the

direction of photography. Determined after determining the direction of the angle of photography. Photography has changed the direction of the screen image features and the

mood will also change.
Positive Shooting:
Conducive to the performance of filming in front of the positive features of the object, can fully show the horizontal lines on the screen. Easy to be taken this positive

solemn, serene atmosphere and object symmetry. Portraits, when people can see the full facial features and expressions, there is intimacy. Positive film, due to the horizontal

lines of the subject easy to level with the viewfinder frame parallel to the main screen and if a very large area, they will be the main horizontal line block, there is no way

to make our line of sight deep stretch. This composition will appear dull, and the lack of three-dimensional sense of space.
The back of the shooting:
The back of the shooting is the subject of being behind the camera. This direction is often used for the main characters take the picture, the main characters and the

background can be integrated. Things in the background is the main object of concern to people. The back of the shooting did not attach importance to the facial expression, but

it focused people’s attitude to the performance of the heart,price of Dell INSPIRON 2500 battery mainly the image of language.
Is the side shooting
This refers to being left or being right. This direction applies to the performance of the main characters has a unique place or time. First, help to highlight the positive

side of the outline of figures and lines. In the emotional exchange between the main characters shooting when two people can move and look lively show.
Xiece direction of shooting
This is what we usually say that the left front, right front and left rear, right rear. This film features the direction of the horizontal lines is to make the subject into a

slash on the screen, so that objects produce significant changes in physical perspective, but can expand the capacity of the screen, make the picture lively. Secondly, we take

the perspective that the problem is. It is the camera with the subject in the camera’s relative position on the vertical plane. Or the direction in photography from the fixed

case, the camera between the subject and the relative height. Different because of the relatively high, they form a flat, Yang, overlooking the three different camera angles.
-Ping:
Is the camera and the subject in the same horizontal line to shoot. This time the subject is not easy to deformation, in particular activities-ping character scenes, people

feel equal and intimate. When shooting natural scenery, the horizon of the treatment is very important. We are down to emphasize the symmetry, can the horizon in the middle

position. But under normal circumstances, should avoid the case of split-screen average of the horizon, because that is the case, vision and close-range will be compressed in

the middle of a line, the screen flat, dull.
Yang photo
In this case, the camera below the subject is taken up. Prominent subject in favor of imposing tall, able to grow up the tree so the scene unfolding on the screen fully. Photo

by Yang close to the ground moving objects can also be used exaggerated vacated, jumping and other activities. Yang took the time people pay attention to is that fat people

face, try not to compare this film.
Overhead
Camera above the subject is shot down. This perspective as if long-term perspective, the current scene from near to far from the bottom on the screen unfolds to full level.

Conducive to the performance of the scene on the ground level, the number, location, etc., can give a vast and profound experience.
4, engraved note changes the depth of field inside the LCD.price of Dell Inspiron 9400 battery Performance is often a good depth of field can make a picture to life. In our viewfinder before pressing the

shutter, we should always pay attention to the inside of the LCD screen to show the depth of field changes from the specific choice will be based on different aesthetic to each

person identified, regardless of which do not want to screen must take into account a fuzzy shot of the main service to it.
5, as much as possible to use a tripod.
6, you can select a variety of film topics. We often see the performance of macro photography flowers and insects, fish, generally, in fact, we might try taking pictures of

people, macro photography is suitable for some things.
7, a good selection of focus. When doing macro photography is the focus of most can not ignore the choice, we should focus on things that can best performance characteristics,

some of the most out of color.

First, take the equipment to prepare

More preparation before shooting some of the battery to ensure that the battery ran out during the shoot, and do not miss important scenes. Of course, some other commonly used preparation is also very important parts, such as to be ready to tape, Memory Stick Memory Stick. In addition, it can be equipped with Teleconverter head, wide-angle lens, small tripod, and video light and flash and other equipment, for later use. In addition, in order to get a better recording, you may want to own a microphone in order to clear the spacious venue for live recording.

Second, the record of the activities of students

Students will graduate, and I feel sure will be a bit special, this time in the dorm room to shoot some content, such as students in order books, clothes, gifts for graduation. This is the first scene of the story,TOSHIBA PA3457U-1BRS Replacement battery do not forget the film Oh! At this moment, the feelings of the students are very complex, when the students one by one to the dormitory shooting about, in particular, pay attention to film their faces. In order to be able to screen themselves shown, you can install the camera on a tripod, use the remote for the self-timer. You can also conduct live interviews, so that students feel about this time, when the footage to be as close as possible to students, in order to access the contents of all clear record.

Third, the shooting school environment

You can shoot a little bit earlier, so that schools can be taken before the graduation ceremony, school and school environment. Sign in the school before the shooting, this must not forget, it will make you leave a permanent mark, always remember this name. When shooting wide-angle lens to use in order to clearly see the school name.

Film school buildings, this can not let go, a few years of school life, every day see, if graduated, it can not always go back to school, come quickly captured. Shooting tall buildings, try to put your camera lens facing up and then shoot, so you can show the tall school buildings.

Shooting playground. Playing in the playground all day, for exercise, etc., will also allow you to see the happy memories from after-school life. Shooting spacious square, from the height to photography, to shoot more wide scene.Sony PCGA-BP2V laptop battery You can pan the method to collect all the lens into the playground.

There are also libraries, canteens, quiet road, a broad field, and so lived experiment where these places should be taken down.

Fourth, the classroom shooting

From now on no longer and the students and teachers spent in the classroom. If the time to come to a halt just fine. Shooting to scan the whole class first, then shooting the classroom of the brand, very memorable. You can prepare in advance so that students seated, shooting the scene of what they read and write. At this time shooting to note that if standing in the corridor to shoot the classroom situation, it is prone to backlight situation, or choose the location of the window to shoot it.

For the teacher a goodbye to the last lesson, the teacher what to say it? Photographed Come on, let the teacher’s parting words always in mind. Then pay attention, if not to occupy a favorable position, the situation may appear backlit. To avoid the backlight, you can use the zoom function (the focus pull away), the expansion of video objects, so that the viewfinder or LCD screen light is not strong, only to shoot. You can also use the backlight compensation button on the camera to shoot.

Fifth, take the ceremony venue

First of all to choose the right shooting position, the position should be taken against the right front or left front and back windows, the location of choice.

Can be taken at the shooting scene into the venue to see how the students approach,battery for dell xps m1330 of course, can not be less close-up. When you are familiar with the students arrived at the venue, do not panic and swing the camera, should be mindful of when he came in front of you start recording or photography. When they close, with the pace of the frequency of mobile cameras.

First, the whole hall with wide-angle shooting situations, allowing people to understand the whole process, while not easy because the hand shake shaking leaving the entire screen appears. After then zoom to the familiar figure closer to the students, then you need to open the electronic image stabilization function.

Do not always when shooting them in the same camera angles, so the whole image will change due to the lack of people feel monotonous, so it should be in the range of environmental conditions as often as possible to allow the change to take place, so much easier After shooting a masterpiece of editing a content-rich, if you want to change the angle, should be taken on the aisle or against the wall, it is a good picture of stability. Less in the action scenes, you can choose to use the camera shooting some pictures, the effect will be better.

The next president can take speech, speech and other scenes of student representatives. Then you can synchronize with an external microphone recorded the sound, relatively noisy because of the venue, though the camera’s built-in microphone recording can provide a whole site, but use an external microphone can be more accurately controlled, so that your sound more clearly, to high level of effect.

Finally, the students take the diploma and degree certificates to receive the scene, the graduation ceremony to receive their diplomas from the call name, the middle is best not to stop shooting.price of Dell LATITUDE D500 battery Of course this time the subject must be followed closely in order to maintain the effect of continuous shooting.

Six, live interviews students

After the meeting, the students talking to each other, reluctant to say something in the words of farewell, then do not miss. In addition, their hands diploma, degree certificates, also have taken off with close-ups.

During the shooting, usually by way of documentary filmmaking, so the whole process of the film would seem tedious, lacking vivid picture content. Then we might come to a impromptu interview to make the students talk about the mood. Before shooting the best of those interviewed make a simple preparation, such as a simple garment finishing, to talk about meditation and other content, access to content should not be too long, to the words of blessing and encouragement for the theme. In the film interview,APPLE A1181 Battery the interviewer you can be farther away, and then the camera than in front of his chest, it is best not to use the general scene, took the microphone and handed him to shoot himself in order to avoid recording over the surrounding noise large, then shoot button. Shooting a few seconds to press the capture key in advance, to prevent an unsuccessful delays.

Five functions of a firewall

In general, the computer firewall has the following features:

1. Allows network administrators to define a central point to prevent unauthorized users access to the internal network.
2. Can easily monitor network security and the police.dell xps m1730 battery

3. As deployment of NAT (Network Address Translation, network address translation) of the location, use of NAT technology, the limited IP address dynamic or static IP address with the internal correspond, to alleviate the address space shortage.
4. Internet use is the cost of the audit and record one of the best locations. Network administrator can provide the management costs of Internet connectivity situation, to identify the location of potential bandwidth bottlenecks and to the accounting model based on this body to provide department-level accounting.
5. Can be connected to a single network segment, and the internal network segment physically separated, and in the deployment of WWW server and FTP server, publish it as internal information to external sites. From a technical point of view, the so-called cease-fire zone (DMZ).

Comparison of two kinds of firewall technology

Packet filter firewall

Advantages: lower price, performance overhead, faster processing speed
Disadvantages: the definition of complex and prone to cause problems due to improper configuration.Dell Vostro 1510 Replacement battery Let the packet directly, easily lead to data-driven potential risk of attack

Proxy Firewall

Built specifically to enhance the security of the application prepared by Proxy, a thorough understanding of related services to the order of data packets between security processing. Slower, less for high-speed network (ATM or Gigabit Ethernet, etc.) applications

The two categories firewall

Although the firewall after the development of several generations of the above, but in accordance with the firewall between internal and external data processing methods can be roughly divided into two systems will be firewalls:JVC bn-vf707 laptop battery packet filtering firewall and proxy firewalls (application layer gateway firewall). The former Israeli Checkpoint Firewall and Cisco PIX firewall as the representative of the company, which the United States NAI’s Gauntlet firewall as the representative.

1. Packet filter firewall

The first generation: static packet filtering. This type of firewall filtering rules based on defined review of each packet to determine whether a packet filtering rule with a match. Filtering rules based on data in the packet header information develop. Header information including the IP source address, IP destination address, transport protocol (TCP, UDP, ICMP, etc.), TCP / UDP destination port, ICMP message types. The type of firewall packet filtering is a basic principle to follow is the “principle of least privilege”, that administrators want to explicitly allow those packets through to prohibit other data packets.

Second Generation: Dynamic packet filtering

2. Proxy Firewall

The first generation: The proxy firewall. Proxy firewall,battery for HP Compaq Business Notebook NX6320 also known as application layer gateway (Application Gateway) firewall. The firewall through a proxy (Proxy) to a TCP connection technology in the whole process. Data packets sent from within the firewall after such treatment, as if the same card from outside the firewall, which can mask the role of the internal network structure. This type of firewall, network security experts and the media is recognized as the most secure firewall. Its core technology is the proxy server technology.

The so-called proxy server, is representing clients in the server connection request procedure. When the proxy server to get a client connection to intention, they will verify the customer requests, and after a specific security application processing of the Proxy connection request, the request will be processed is passed to the real server, then receive the server response, and do After further processing, will be the ultimate answer to the requesting client. Proxy server in the external network to internal network application services played a role in the middle of transfer.

The most prominent type of firewall proxy advantage is security. Since each connection between inside and outside the network go through Proxy intervention and transformation, through specialized for specific services such as security Http prepared for processing of the application and then submit a request by the firewall itself and the response, not to the internal and external networks direct the computer to any chance of the session, thus avoiding the use of data-driven type of intruder attack invasion of the internal network. Type of firewall packet filtering is difficult to completely avoid this vulnerability. A stranger as you would like to submit a statement, an important figure in the same statement if you first give your lawyer, and lawyers will review your statement, make sure there is no negative impact on later handed over by him the stranger. In the meantime, the presence of a stranger you know nothing of, if you were violated,price of HP Compaq Business Notebook 6710b battery his face will be your lawyer and your lawyer of course, more clearly than you how to deal with people.

Proxy Firewall’s biggest drawback is that relatively slow, when users outside the network gateway to the relatively high throughput requirements, (such as the time required to achieve 75-100Mbps) proxy firewall will become the bottleneck between the inside and outside the network. Fortunately, the current speed of the user access to Internet are generally much lower than this figure. In reality, we must consider the type of firewall uses packet filtering to meet the speed requirements of the situation, most of the high-speed network (ATM or Gigabit Ethernet, etc.) between the firewall. Computer Fundamentals

The second generation: adaptive proxy firewall

Adaptive agent technology (Adaptive proxy) was recently implemented in commercial application firewall a revolutionary technology. It can be combined with proxy type of firewall security and high-speed packet filtering firewall, etc., without loss of security in the basis of the performance of the proxy firewall more than 10 times. Composition of the basic elements of this type of firewall,battery for HP Pavilion zv5000 Battery there are two: adaptive proxy server (Adaptive Proxy Server) with dynamic packet filter (Dynamic Packet filter).

Adaptive agents in the dynamic packet filter and a control channel between. In the firewall configuration, users will need only type of service, security level and other information through the appropriate administrative interface Proxy settings on it. Then, the adaptive agent to be based on user configuration information, the decision is to use the proxy service agent requests from the application layer or from the network layer forwarding packets. If the latter, it will notify the packet filter to dynamically change filtering rules to meet the speed and safety of users of the dual requirements.