Building Internet Firewalls |TOP|

Firewalls, critical components of today's computer networks, effectively protect a system from most Internet security threats. They keep damage on one part of the network--such as eavesdropping, a worm program, or file damage--from spreading to the rest of the network. Without firewalls, network security problems can rage out of control, dragging more and more systems down.

Building Internet Firewalls

Like the bestselling and highly respected first edition, Building Internet Firewalls, 2nd Edition, is a practical and detailed step-by-step guide to designing and installing firewalls and configuring Internet services to work with a firewall. Much expanded to include Linux and Windows coverage, the second edition describes:

Like the bestselling and highly respected first edition, Building Internet Firewalls, 2nd Edition, is a practical and detailed step-by-step guide to designing and installing firewalls and configuring Internet services to work with a firewall. Much expanded to include Linux and Windows coverage, the second edition describes:

This document describes options for connecting to and from the internet usingCompute Engine resources that have private IP addresses. This is helpfulfor developers who create Google Cloud services and for networkadministrators of Google Cloud environments.

The Cloud NAT service allows Google Cloud VM instances that don'thave external IP addresses to connect to the internet. Cloud NATimplements outbound NAT in conjunction with adefault route to allow your instances to reach the internet. It doesn't implement inbound NAT.Hosts outside of your VPC network can respond only to established connectionsinitiated by your instances; they cannot initiate their own connections to yourinstances using Cloud NAT. NAT is not used for traffic within Google Cloud.

When you created the VM instances earlier in this tutorial, they didn't have accessto the internet, because no external IP address was assigned and Cloud NAT was notconfigured. Therefore, the startup script that installs Apache could not completesuccessfully.

If you're serving traffic to the internet, you need to allocate an externaladdress for the load balancer. You can allocate an IPv4 address, an IPv6address, or both. In this section, you reserve static IPv4 and IPv6 addressessuitable for adding to DNS.

Your VMs can now serve traffic to the internet and can fetch data from theinternet. You can also access them using SSH in order to perform administrationtasks. All of this functionality is achieved using only private IP addresses,which helps protect them from direct attacks by not exposing IP addressesthat are reachable from the internet.

The Great Firewall (GFW; simplified Chinese: 防火长城; traditional Chinese: 防火長城; pinyin: Fánghuǒ Chángchéng) is the combination of legislative actions and technologies enforced by the People's Republic of China to regulate the Internet domestically.[1] Its role in internet censorship in China is to block access to selected foreign websites and to slow down cross-border internet traffic.[2] The Great Firewall operates by checking transmission control protocol (TCP) packets for keywords or sensitive words. If the keywords or sensitive words appear in the TCP packets, access will be closed. If one link is closed, more links from the same machine will be blocked by the Great Firewall.[3] The effect includes: limiting access to foreign information sources, blocking foreign internet tools (e.g. Google Search,[4] Facebook,[5] Twitter,[6] Wikipedia,[7][8] and others) and mobile apps, and requiring foreign companies to adapt to domestic regulations.[9][10]

The internet in China arrived in 1994,[21] as the inevitable consequence of and supporting tool for a "socialist market economy". Gradually, while Internet availability has been increasing, the Internet has become a common communication platform and tool for trading information.

The latter definition of online activities punishable under CL97, or "crimes carried out over computer networks", is used as justification for the Great Firewall, and can be cited when the government blocks any ISP, gateway connections, or any access to anything on the internet. The definition also includes using the internet to distribute information considered "harmful to national security," and using the internet to distribute information considered "harmful to public order, social stability, and Chinese morality." The central government relies heavily on its State Council regulators to determine what specific online behavior and speech fall under these definitions.[citation needed]

As part of the Great Firewall, beginning in 2003, China started the Golden Shield Project, a massive surveillance and censoring system, the hardware for which was provided by mostly U.S. companies, including Cisco Systems. The project was completed in 2006, and is now carried out in buildings with machines manned by civilians and supervised by China's national police force, the Public Security Bureau (PSB). The main operating procedures of the gatekeepers at the Golden Shield Project include monitoring domestic websites, email, and searching for politically sensitive language and calls to protest. When damaging content is found, local PSB officials can be dispatched to investigate or make arrests. However, by late 2007, the Golden Shield Project proved to operate sporadically at best, as users had long adapted to internet blocking by using proxy servers, among other strategies, to make communications and circumnavigate to blocked content.[32]

Internet cafés, an extremely popular way of getting online in developing countries and where fewer people can afford a personal computer, are regulated by the Chinese government and by local Chinese government officials. Minors (in China, those under the age of 18) are not allowed into Internet cafés, although this law is widely ignored, and when enforced, has spurred the creation of underground "Black Web Bars" visited by those underage. As of 2008, internet cafés were required to register every customer in a log when they used the internet there. These records may be confiscated by either local government officials or the PSB. To illustrate local regulation of internet cafés, in one instance, a government official in the town of Gedong lawfully banned internet cafés from operating in the town because he believed them to be harmful to minors, who frequented them to play online games (including those considered violent) and surf the internet. However, internet cafés in this town simply went underground, and most minors were not deterred from visiting them.[33]

Article 15 of a September 20, 2000 document from the Chinese State Council, posted by the Xinhua News Agency, lists 9 categories of information which should be censored, blocked, or filtered from access to the citizens using the internet within China:

To filter this content, the Chinese government not only uses its own blocking methods, but also heavily relies on internet companies, such as ISPs, social media operators such as Weibo,[77] and others to actively censor their users.[78] This results in private companies censoring their own platform for filtered content, forcing Chinese internet users to use websites not hosted in China to access this information. Much of this information is related to sensitive topics.[79] The Great Firewall's goal is perceived by the Communist Party as helping to protect the Chinese population by preventing users from accessing these foreign websites which, in their opinion, host content which would be 'spiritual pollution', (清除精神污染运动), as well as information about these sensitive topics.[80] These topics include:

The Cybersecurity Law behind the firewall being targeted at helping increase internet user privacy, increased protections on personal data, and making companies more responsible for monitoring bad actors, in hopes to make a safer place on the internet for Chinese citizens.[84] Despite this, there have been growing criticisms that the actions of the Chinese government have only hurt Chinese free speech, due to increased censorship, and lack of non-sanctioned sources of information, such as Wikipedia and many English news sources.[85] This has resulted in reports of some cases of legal persecution of those charged with spreading this information.[80]

Aside from the social control aspect, the Great Firewall also acts as a form of trade protectionism that has allowed China to grow its own internet giants, such as Tencent, Alibaba, and Baidu.[89][90] China has its own version of many foreign web properties, for example: Bilibili and Tencent Video (YouTube), Sina Weibo (Twitter), Qzone (Facebook), WeChat (WhatsApp), Ctrip (Orbitz and others), and Zhihu (Quora).[91] With nearly one quarter of the global internet population (700 million users), the internet behind the GFW can be considered a "parallel universe" to the Internet that exists outside.[12]

While the Great Firewall has had an impact on Chinese citizens' ability to use the internet to find information about sensitive topics about the Communist Party, it has not completely stopped them from doing so. The firewall itself has caused much frustration amongst both individuals and internationally operating companies in China, many of whom have turned to VPNs, speaking in codes,[92] and other methods to retain their access to the international internet.[93]

The use of VPNs in China can provide individuals access to the international internet, but in China, it can be a potential legal risk. In 2017, the Chinese government declared all unauthorized VPN services to be illegal.[94] An example of the use of this punishment is Vera Zhou, a student at the University of Washington, who, when visiting her Hui parents in Xinjiang, China, used a VPN to access her school homework. She was arrested and sent to a Xinjiang internment camp from October 2017 until March 2018, followed by house arrest after her release. She was not able to return to the US until September 2019.[95][96] 041b061a72