What actually is a proxy firewall?


A proxy firewall

A proxy firewall, in contrast to a packet-oriented firewall, is able to monitor and filter application-level communication. It protects networks and their resources against unwanted or dangerous traffic.

The Proxy Firewall is also called Application Layer Firewall or Application Firewall for short. It is a security system that can monitor and filter application-level communication. In contrast to purely packet-oriented firewalls, it not only evaluates address and protocol data from IP packets, but also analyzes traffic directly in the application layer.

It uses the Proxysite rationale by acting as a proxy between the resources to be protected and other networks, such as the Internet. The proxy firewall intercepts all requests to and from the Internet, filters them and passes them on behalf of or blocks them. At the same time, the proxy firewall can cache functions of a proxy server bar. All connections from the network to be protected or from the protected network terminate the proxy firewall itself. As a result, it acts as an independent communication partner for the target and source systems.

Through this proxy function, the proxy firewall can analyze the data contiguously up to layer seven of the OSI layer model. Compared to the target system, the proxy firewall behaves like a client, like a server to the requesting client.


To be able to analyze and filter the traffic, the proxy firewall must know the protocols to be monitored. It has its own filter for each protocol, such as HTTP, SMTP, FTP or DNS. In this, unwanted protocol options or data communications can be prohibited. The proxy-based firewall is considered a very secure form of firewall because it blocks direct network traffic between internal and external systems. An internal device can never directly receive a data packet from an external system. The firewall is always in between and at the same time the source and destination of any communication.

The proxy rationale

The proxy policy is based on the proxy function for network services. A proxy works as a proxy for a client who wants to gain access to a particular service. As a result, it shields both services and clients from each other and prevents direct connections between the two communication partners. If a client wants to establish a connection to a service, it first communicates with the proxy. This establishes the connection to the server on behalf of the client. The proxy forwards the data from the client to the server and transmits the data received from the server to the client.

Distinction between transparent and non-transparent proxy

There are two principal ways in which a proxy works. It can be transparent or non-transparent from the client’s point of view. If it is a non-transparent proxy, the client must be informed about its existence. For this purpose, the client and its software receive a special proxy configuration, which ensures that the traffic to the outside is first addressed to the proxy. If this configuration does not exist, the client cannot communicate through the proxy. However, as the proxy usually provides the only communication path to other networks, communication to the outside without the corresponding proxy configuration is generally cut off.

By contrast, the transparent proxy knows nothing about the client’s existence. The transparent proxy intercepts the communication requests of the client to the outside and intervenes as deputy instance. Outwardly, the transparent proxy acts like the non-transparent proxy as a communication partner. However, the client assumes that it communicates directly with the target system. This is made possible by the manipulation of the IP addresses. The clients do not need a special configuration for a transparent proxy.

The operation of a proxy firewall

Since the proxy firewall carries all communication on behalf of the clients to be protected, it can analyze the transmitted data in great detail. It verifies that the communication complies with the previously established protocol rules and policies and allows traffic to be blocked or blocked.

The received packets can not only be examined for source and destination addresses or ports, but the information can be analyzed directly at the application level. Due to the address conversion taking place through the proxy firewall, the clients remain completely hidden in the network to be protected.

Merry Christmas 2017 Wishes

merry christmas 2018 wishes

Merry Christmas 2017 Greetings

Although Christmas has turned out of religion and has nothing to do with it, most families have been adopted to arrange a tree and exchange gifts.

Like most decks of red, green and gold in this season, we cannot help but feel. Here are some quotes, greetings, and messages to greet your loved ones with Christmas, when you meet them or stay in WhatsApp.

Here are some messages for your most loved about Merry Christmas 2017 Wishes

It is Christmas for you as you think of me in my life. The warmth and comfort that comes with this season reminds me of you

Give it a season and feel to love and share. Christmas is a time when we are blessed with our blessings and reach those who touched our lives.

Thank you for being such a wonderful friend/sibling you are the best in the Christmas season.

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Santa has already got me on my list! Happy Christmas!

About this holiday season makes me think about all the pleasures that have been shown to me throughout the year. I love you.

Could your holidays be blessed without ending happiness and love? Due to such an amazing friend/sibling/parent like you, only the best claims. Happy Christmas!

Some have expressed the desire to proceed:

Christmas is the season for peace, joy, and fellowship with family and friends. Could Yuletide fill your heart and house with an abundance of grace, satisfaction, laughter, and harmony?

Christmas is all about sharing, sharing and eating. Will your home be filled with love, light, and rhythm? Happy holidays!

It’s time to gather together when the loved ones. It is a special time to be grateful for all the great blessings in our lives. Have your best wishes and sent that your holiday hopes to be a happy one.

Count your blessings, sing your Christmas Carol, open your gifts, and make a desire under a Christmas tree. You may have a delightful Christmas!

On this special day, we remember the sacrifices we have made for us, and we pay tribute to his memory and prepare ourselves for the support of his soul and for the glory and purity of the universe.

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Some midnight or morning messages for those you celebrate with:

Christmas is a festival spent with your loved ones, and I’m grateful I’ll celebrate it with you.

To be late this season and I’m sure we will have fun memories and future Christmases today.

Hopefully, we’ll share as a Christmas hot and sweet hot cocoa/cup of cups.

I could not wait to spend Christmas with you. It’s a gift I’ve been asking Santa all year.

Christmas Day History 2017:

Why Christmas Day is celebrated here

To send some interesting messages:

Sorry to let you know but Christmas is canceled this year. Apparently, you said Santa was good this year and he died laughing.

This year is the time for Jesus to be grateful because he stopped you a few extra days from the work.

Nutritional of Oranges

Will you eat oranges and get angry?

Oranges can eat, but do not eat too much, it is recommended to eat 1-3 oranges a day. Eat too much at once easy to “get angry”, can promote stomatitis or periodontitis, and yellow skin may appear. Because orange pulp contains a certain amount of organic acids, in order to avoid irritation of the gastric mucosa caused by discomfort, bad stomach. It is recommended not to eat oranges fasting.

Oranges should be timely brushing mouthwash, so as not to harmful to the oral teeth. Poor gastrointestinal function, eat too much oranges, prone to be troubled by the stomach stone. Oranges contain more calories, if we eat too much at once, it will “get angry” to promote stomatitis, periodontitis embolism. Excessive consumption of citrus fruits can cause “orange disease”, appear, the skin yellowing and other symptoms.

Excessive consumption of orange causes “orange disease”

Because oranges contain large amounts of carotenoids, the liver can not be completely decomposed if an overdose or recent intake of too much, the carotene concentration in the blood is too high, will be deposited in the skin angle, causing yellow skin, especially around the palm and nasal cavity The yellowish edge of the skin is more obvious. This is the same thing with yellow cholestatic hepatitis.

Got an orange disease can be no panic, as long as more water, do not eat oranges, citrus and other fruits, limiting the carotene-rich foods, after a month or so, the skin will return to normal.

Orange tendons do not lose

When many people in life eat oranges, they like to pull off the white jelly outside the jellyfish. In fact, this method of eating is unscientific.

Jujube outside the white mesh network is often called “orange network.” Both from the traditional Chinese medicine and modern nutrition point of view, the orange juicers are very useful. Chinese medicine that orange network with collaterals phlegm, Shun Qi Huoxuezhizhi, not only chronic bronchitis, coronary heart disease and other chronic diseases in patients with diet Jiapin, but also caused by Cough caused by chest XU pain uncomfortable still adjuvant therapy. Modern nutrition research believes that orange network contains a substance called Lu Ding. Road D can maintain normal vascular elasticity and tightness, can reduce the brittleness and permeability of the vascular wall, to prevent stroke in hypertensive patients with cerebral hemorrhage, diabetic retinal hemorrhage occurred. For people who usually have bleeding tendency, especially those with tendency to hardening of the arteries, eating oranges is more beneficial and harmless.

Taboo food

Oranges contain a variety of vitamins, minerals, cellulose and carotene, have good nutritional value, loved by the people. Carotene is converted to vitamin A in the liver. But too much carotene in the liver can not be transformed in time, with the blood circulation throughout the body. Therefore, eating oranges will happen carrot hyperlipidemia. Manifested as hand, palm skin yellow dye, accompanied by loss of appetite, vomiting, malaise and other symptoms, and sometimes be suspected of hepatitis. To eat too much orange there will be “angry” performance, such as angular cheilitis, gingivitis, glossitis, constipation and other symptoms. Have the above symptoms should stop eating orange for 1-2 weeks.

Not with radish food

Radish into the body, it will quickly produce a substance called sulfate, and quickly metabolized to produce an anti-thyroid substance – thiocyanate. If you eat oranges at this time, the flavonoids in the orange will be broken down in the intestine, and converted to hydroxybenzoic acid and ferulic acid, they can enhance the inhibitory effect of thiocyanate on the thyroid gland, which induced or lead to goiter.

Oranges and milk should not be the same food

Milk protein easily with orange acid and vitamin C reaction, solidified into blocks, not only affect the digestion and absorption, but also cause abdominal distension, abdominal pain, diarrhea and other symptoms. Therefore, before and after eating oranges within 1 hour should not drink milk.

Older people want to eat less

Gastrointestinal, kidney, lung function Deficiency constitution of the elderly can not eat, so as to avoid abdominal pain, Yaoxisuanruan and other symptoms.

Yin physique do not eat

Chinese medicine believes that oranges warm, eat easy to get angry, especially those who belong to the yin deficiency Yang Sheng constitution, the best to eat, otherwise there will be mouth sores, dry mouth, throat pain, constipation and other symptoms. Suggested to eat citrus, can avoid the fire symptoms.

Children greedy, eat oranges, easy to get angry. If the children eat oranges too much, the so-called “get angry” manifestations, such as glossitis, periodontitis, pharyngitis, etc., should be suspended for 1-2 weeks, eat again.

Patients with gastrointestinal diseases should eat less

Friends suffering from gastrointestinal diseases is best to eat oranges, poor gastrointestinal function, eat too much oranges, prone to be troubled by stomachache