A demilitarized zone network, or DMZ, is a subnet that creates an extra layer of protection from external attack. Network administrators must balance access and security.

But some items must remain protected at all times.

Use it, and you’ll allow some types of traffic to move relatively unimpeded. But you’ll also use strong security measures to keep your most delicate assets safe.

Some people want peace, and others want to sow chaos. The two groups must meet in a peaceful center and come to an agreement.

In military terms, a demilitarized zone (DMZ) is a place in which two competing factions agree to put conflicts aside to do meaningful work. A strip like this separates the Korean Peninsula, keeping North and South factions at bay.

When implemented correctly, a DMZ network should reduce the risk of a catastrophic data breach. Public-facing servers sit within the DMZ, but they communicate with databases protected by firewalls.

In 2019 alone, nearly 1,500 data breaches happened within the United States. Sensitive records were exposed, and vulnerable companies lost thousands trying to repair the damage.

While a network DMZ can’t eliminate your hacking risk, it can add an extra layer of security to extremely sensitive documents you don’t want exposed.

Any network configured with a DMZ needs a firewall to separate public-facing functions from private-only files. But developers have two main configurations to choose from.

This configuration is made up of three key elements. Configure your network like this, and your firewall is the single item protecting your network.

A single firewall with three available network interfaces is enough to create this form of DMZ. But you’ll need to create multiple sets of rules, so you can monitor and direct traffic inside and around your network.

Is a single layer of protection enough for your company. If not, a dual system might be a better choice.

Set up your front-end or perimeter firewall to handle traffic for the DMZ. Set up your internal firewall to allow users to move from the DMZ into private company files.

Companies even more concerned about security can use a classified militarized zone (CMZ) to house information about the local area network. Choose this option, and most of your web servers will sit within the CMZ.

Hackers often discuss how long it takes them to move past a company’s security systems, and often, their responses are disconcerting. But a DMZ provides a layer of protection that could keep valuable resources safe.

Companies often place these services within a DMZ: An email provider found this out the hard way in 2020 when data from 600,000 users was stolen from them and sold.

For example, one company didn’t find out they’d been breached for almost two years until a server ran out of disc space. A DMZ network makes this less likely.

In fact, some companies are legally required to do so. For example, some companies within the health care space must prove compliance with the Health Insurance Portability and Accountability Act.

Building a DMZ network helps them to reduce risk while demonstrating their commitment to privacy. Network administrators face a dizzying number of configuration options, and researching each one can be exhausting.

DMZ server benefits include: You’ll also set up plenty of hurdles for hackers to cross.

DMZ server drawbacks include: Only you can decide if the configuration is right for you and your company.

If you’re struggling to balance access and security, creating a DMZ network could be an ideal solution. By housing public-facing servers within a space protected by firewalls, you’ll allow critical work to continue while offering added protection to sensitive files and workflows.

Cyber Crime: Number of Breaches and Records Exposed 2005-2020. (October 2020).

As a Hacker, How Long Would It Take to Hack a Firewall. Quora.

(November 2019). ZD Net.

Email Provider Got Hacked, Data of 600,000 Users Now Sold on the Dark Web. (April 2020).

FTP Remains a Security Breach in the Making. (July 2014).

Cost of a Data Breach Report 2020. IBM Security.

In computing, a server is a piece of computer hardware or software (computer program) that provides functionality for other programs or devices, called “clients”. This architecture is called the client–server model.

A single server can serve multiple clients, and a single client can use multiple servers. A client process may run on the same device or may connect over a network to a server on a different device.

Client–server systems are usually most frequently implemented by (and often identified with) the request–response model: a client sends a request to the server, which performs some action and sends a response back to the client, typically with a result or acknowledgment. Designating a computer as “server-class hardware” implies that it is specialized for running servers on it.

The use of the word server in computing comes from queueing theory, where it dates to the mid 20th century, being notably used in Kendall (1953) (along with “service”), the paper that introduced Kendall’s notation. In earlier papers, such as the Erlang (1909), more concrete terms such as “[telephone] operators” are used.

In computing, “server” dates at least to RFC 5 (1969), one of the earliest documents describing ARPANET (the predecessor of Internet), and is contrasted with “user”, distinguishing two types of host: “server-host” and “user-host”. The use of “serving” also dates to early documents, such as RFC 4, contrasting “serving-host” with “using-host”.

The Jargon File defines “server” in the common sense of a process performing service for requests, usually remote, with the 1981 (1.1.0) version reading:. SERVER n.

Strictly speaking, the term server refers to a computer program or process (running program). Through metonymy, it refers to a device used for (or a device dedicated to) running one or several server programs.

In addition to server, the words serve and service (as verb and as noun respectively) are frequently used, though servicer and servant are not.[a] The word service (noun) may refer to the abstract form of functionality, e.g. Web service.

Windows service. Originally used as “servers serve users” (and “users use servers”), in the sense of “obey”, today one often says that “servers serve data”, in the same sense as “give”.

The server is part of the client–server model. in this model, a server serves data for clients.

This is in contrast with peer-to-peer model in which the relationship is on-demand reciprocation. In principle, any computerized process that can be used or called by another process (particularly remotely, particularly to share a resource) is a server, and the calling process or processes is a client.

For example, if files on a device are shared by some process, that process is a file server. Similarly, web server software can run on any capable computer, and so a laptop or a personal computer can host a web server.

While request–response is the most common client-server design, there are others, such as the publish–subscribe pattern. In the publish-subscribe pattern, clients register with a pub-sub server, subscribing to specified types of messages.

Thereafter, the pub-sub server forwards matching messages to the clients without any further requests: the server pushes messages to the client, rather than the client pulling messages from the server as in request-response.

A server computer can serve its own computer programs as well. depending on the scenario, this could be part of a quid pro quo transaction, or simply a technical possibility.

Almost the entire structure of the Internet is based upon a client–server model. High-level root nameservers, DNS, and routers direct the traffic on the internet.

There are exceptions that do not use dedicated servers. for example, peer-to-peer file sharing and some implementations of telephony (e.g.

Hardware requirement for servers vary widely, depending on the server’s purpose and its software. Servers often are more powerful and expensive than the clients that connect to them.

The name server is used both for the hardware and software pieces. For the hardware servers, it is usually limited to mean the high-end machines although software servers can run on a variety of hardwares.

Since servers are usually accessed over a network, many run unattended without a computer monitor or input device, audio hardware and USB interfaces. Many servers do not have a graphical user interface (GUI).

Remote management can be conducted via various methods including Microsoft Management Console (MMC), PowerShell, SSH and browser-based out-of-band management systems such as Dell’s iDRAC or HP’s iLo.

Availability would have to be very high, making hardware reliability and durability extremely important. Mission-critical enterprise servers would be very fault tolerant and use specialized hardware with low failure rates in order to maximize uptime.

Servers typically include hardware redundancy such as dual power supplies, RAID disk systems, and ECC memory, along with extensive pre-boot memory testing and verification. Critical components might be hot swappable, allowing technicians to replace them on the running server without shutting it down, and to guard against overheating, servers might have more powerful fans or use water cooling.

Server casings are usually flat and wide, and designed to be rack-mounted, either on 19-inch racks or on Open Racks.

These will normally have very stable power and Internet and increased security. Noise is also less of a concern, but power consumption and heat output can be a serious issue.

A server farm or server cluster is a collection of computer servers maintained by an organization to supply server functionality far beyond the capability of a single device. Modern data centers are now often built of very large clusters of much simpler servers, and there is a collaborative effort, Open Compute Project around this concept.

A class of small specialist servers called network appliances are generally at the low end of the scale, often being smaller than common desktop computers.

a laptop. In contrast to large data centers or rack servers, the mobile server is designed for on-the-road or ad hoc deployment into emergency, disaster or temporary environments where traditional servers are not feasible due to their power requirements, size, and deployment time.

To facilitate portability, features such as the keyboard, display, battery (uninterruptible power supply, to provide power redundancy in case of failure), and mouse are all integrated into the chassis.

Proprietary operating systems such as z/OS and macOS Server are also deployed, but in much smaller numbers. Servers that run Linux are commonly used as Webservers or Databanks.

Specialist server-oriented operating systems have traditionally had features such as:. In practice, today many desktop and server operating systems share similar code bases, differing mostly in configuration.

In 2010, data centers (servers, cooling, and other electrical infrastructure) were responsible for 1.1-1.5% of electrical energy consumption worldwide and 1.7-2.2% in the United States. [needs update] One estimate is that total energy consumption for information and communications technology saves more than 5 times its carbon footprint in the rest of the economy by increasing efficiency.

A proxy server is an intermediary server that retrieves data from an Internet source, such as a webpage, on behalf of a user. They act as additional data security boundaries protecting users from malicious activity on the internet.

Common uses include facilitating anonymous Internet browsing, bypassing geo-blocking, and regulating web requests. Like any device connected over the Internet, proxies have associated cybersecurity risks that users should consider before use.

Typically, a user accesses a website by sending a direct request to its web server from a web browser via their IP address. The web server then sends a response containing the website data directly back to the user.

A proxy server acts as an intermediary between the user and the web server. Proxy servers use a different IP address on behalf of the user, concealing the user’s real address from web servers.

Learn how to respond to the MOVEit Transfer zero-day >. A standard proxy server configuration works as follows:

Below is a classification of some of the different types of proxy servers. A forward proxy (commonly known as a ‘proxy’) is a type of proxy server that typically passes requests from users in an internal network to the Internet via a firewall.

Forward proxies are configured to either ‘allow’ or ‘deny’ the user’s request to pass through the firewall to access content on the Internet.

The web server sends its response to the proxy. The proxy then sends this response back to the user.

Learn how to respond to the Fortigate SSL VPN vulnerability >. A forward proxy will first check if the user’s requested information is cached before retrieving it from the server.

If the requested information is cached, the proxy will send it directly to the user. If the proxy denies the user’s request, it sends the user an error or redirect message.

A reverse proxy is a type of proxy server that typically passes requests from the Internet through to users in an internal network via a firewall. essentially, a forward proxy in ‘reverse’.

Reverse proxies are configured to restrict and monitor users’ access to web servers containing sensitive data. User requests are passed through the Internet via a firewall to the reverse proxy.

A reverse proxy will first check if the user’s requested information is cached before retrieving it from the server. The proxy stores any cached information, eliminating the need to request it from the server.

If the proxy denies the user’s request, it sends the user an error or redirect message. High anonymity proxies offer the most security to a user.

These proxies routinely change IP addresses when making requests to web servers, allowing a high level of privacy. An anonymous proxy (also called a distorting proxy) conceals a user’s real IP address when they visit a website.

Anonymous proxies identify as proxies in web server requests. Anonymous proxies are one of the most commonly used proxies.

TOR (The Onion Router) is a free, open-source web browser that routes users’ internet traffic through a network of volunteer servers to provide anonymity. TOR helps remove visibility over Internet activity by encrypting, decrypting, and re-encrypting web requests many times before they reach the destination server – a process known as ‘onion routing’.

A transparent proxy is the opposite of an anonymous proxy. As its name suggests, transparent proxies do not conceal any identifying information about the user.

They send a request to the web server that shows as coming directly from the user. Transparent proxies are set up by a network operator or website, not the user, and are commonly used by organizations, public libraries, and schools for website content filtering purposes.

HTTP proxies use the HTTP protocol and are not configured by the user. Instead, they are either configured by the browser or within the website’s interface.

HTTP proxies allow users to browse the web with a different IP address but do not offer any additional privacy or security. All user activity is still visible over the Internet, the same as without a proxy.

While some HTTP proxies allow users to connect to HTTPS websites, enabling encrypted internet connections, this is not always the case. HTTP proxies may completely filter out HTTPS connections or only allow users to connect to unsecured versions of a website, even if it also allows secure connections.

Many HTTP proxies are free and monetize their services by injecting ads into the unsecured connection. Users should exercise caution when accessing HTTP proxies.

The HTTPS proxy works exclusively with web content and cannot be used for any other data types. HTTPS proxies encrypt all web traffic using the HTTPS protocol.

If a user connects to an HTTPS website via an HTTPS proxy, their connection is doubly secured. Find out the differences of HTTP vs HTTPS here.

The SOCKS5 protocol routes users’ traffic through a third-party server – SOCKS proxy server – via TCP (Transmission Control Protocol). SOCKS proxies do not offer their own encryption.

Most SOCKS proxy servers support SHH, which enables secure connections with apps that also support SHH. It’s important to note that even with SHH enabled, SOCKS proxies do not guarantee anonymity.

A SIP (Session Initiation Protocol) proxy works as an intermediary between SIP devices (e.g. telephones) through the SIP protocol.

An SMTP (Simple Mail Transfer Protocol) proxy works as an intermediary for mail transfer through the SMTP protocol. The proxy is configured to allow or deny incoming and outgoing emails based on factors, such as source address, the sender’s server, and even the content of the email.

Organizations need to implement additional email security measures to authenticate incoming emails, such as Sender Policy Framework (SPF) filtering, Domain Key Identified Mail (DKIM), and Domain-Based Message Authentication, Reporting, and Conformance (DMARC). SMTP proxies can also be used to:

FTP is a protocol used for exchanging files over the Internet and internal networks. FTP proxies allow or deny file transfers based on factors, such as source/destination IP addresses and user authentication.

The DHCP (Dynamic Host Configuration Protocol) proxy agent is a network management tool that works as an intermediary between DHCP devices and requests through the DHCP protocol. DHCP servers send network configuration to devices within a network.

Sometimes, devices connected to a subnetwork via a router cannot send configuration requests to the DHCP server. A DHCP proxy agent forwards such devices’ requests to the server, receives the response, and relays this back to the device.

A DNS proxy forwards DNS (Domain Name System) requests from the user to a DNS server. DNS is a system that allows users to enter a domain name (e.g.

When a user enters a domain name, DNS will choose which of the domain’s servers will complete the user’s request. DNS servers can either allow access to a domain or block requests from an IP based on several factors, such as authentication or geolocation restrictions.

DNS proxies can also be used to: A Smart DNS proxy enables users to bypass DNS restrictions such as geo-location restrictions.

DNS servers will usually connect users to the closest web server in their geo-location. Certain online content, such as video streaming services and news platforms, restrict their content based on location.

Oct 21, 2023. Tamara J.

7min Read. A web server stores and delivers files to browsers, making your site accessible to users.

While it’s possible to set up your own server, renting it from a web hosting provider saves you time, money, and effort. Keep reading this article to learn how web servers work, why they’re important, and some of the popular examples.

A web server is a computer that hosts web pages, making them accessible online. When a user loads a site, the web server will retrieve the relevant files and send them to the browser so the user can interact with them.

Web and application servers follow a client-server model. In this structure, one program – the client – requests a resource or service from another program – the server.

HTTP is a protocol used to exchange information between computers. Through the HTTP request process, servers can deliver the site’s HTML document to the user’s web browser, like Google Chrome.

When the HTTP server fails to find or process the requested files, it will send an HTTP error status code to the browser. The most common error message is a 404 error, which means the requested page is missing.

Furthermore, if a web server fails to receive a timely response from another server acting as a proxy or gateway, a 504 error occurs. Web servers can generate both static and dynamic content depending on the installed software.

Meanwhile, a dynamic web server consists of a static web server plus extra software, commonly an application server and databases. A static web server sends files to web browsers without any changes, making them suitable for sites with fixed content like blogs and portfolios.

On the other hand, a web server for a dynamic website updates hosted files using additional software to personalize content based on user interactions. It’s the perfect option for sites like social media platforms and eCommerce stores.

Web servers can handle multiple tasks, such as sending and receiving emails, storing web applications, and processing FTP requests. However, the primary use of a web server is to host websites, making them functional and interactive for users worldwide.

The easiest way to accomplish this is by purchasing web hosting and a domain name from a hosting provider. Website hosting services provide your website with server space to store its files and databases.

Learn everything you need to know about web hosting and domain names in these comprehensive guides: What Is Web Hosting – Web Hosting Explained for Beginners What Is a Domain Name. A Beginner-Friendly Guide.

That’s why choosing a reliable web hosting provider is crucial. Other benefits of having a trusted web host include:

Looking for ways to boost your web server performance. Check out this tutorial on how to monitor website uptime and prevent downtime.

Web hosting companies support different types of servers. For example, Hostinger supports Apache and NGINX, the two leading web servers in the market.

To ensure the best performance, server administrators carry out several tasks: At Hostinger, our web servers are protected by advanced DDoS countermeasures and an AI-powered firewall.

For maximum speed, we use the latest technologies like NVMe SSD storage and AMD EPYC processors running on industry-leading HPE and DELL server hardware. Plus, our data centers are strategically located across four continents.

A web server connects your website to the internet. It consists of hardware and software, each playing a distinct role in processing files.

Besides Apache and NGINX, other web servers in the market include Microsoft Internet Information Services and Lighttpd. Different types of web servers can deliver dynamic content or static content to a browser.

Purchasing a web hosting plan is necessary for any website type. The web host will be responsible for maintaining the server’s security and performance.

Find answers to commonly asked questions about a web server. A web server primarily responds to HTTP requests by delivering static content like web pages and images to a browser.

A web server consists of hardware and software. The hardware side connects to the internet to exchange data, and the software side includes an HTTP server that processes requests and URLs.

When choosing a web server, consider factors like the server’s performance, security features, compatibility with your website’s tech stack, ease of management, support options, and pricing. You can start with Hostinger’s shared server hosting before upgrading to VPS or cloud-based solutions for better performance.

These servers are highly reliable and widely used. The best choice will depend on your specific needs and the technologies your website uses.

Tamara is a Content Editor and digital marketing enthusiast with 2+ years of experience in the IT industry. She loves sharing tips and tricks about SEO, web development, and eCommerce to help others navigate the online sphere.

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Brian is a Content Writer who knows the ins and outs of digital marketing and eCommerce. Driven by passion and a dose of caffeine, he constantly looks for better ways to tell complex stories in a simple manner.

Protecting a Web server from compromise involves hardening the underlying Operating System (OS), the Web server application, and the network to prevent malicious entities from directly attacking the Web server. The first step in securing a Web server is hardening the underlying OS.

Many security issues can be avoided if the OSs underlying the Web servers are configured appropriately. Default hardware and software configurations are typically set by manufacturers to emphasize features, functions, and ease of use, at the expense of security.

The practices recommended here are designed to help Web server administrators configure and deploy Web servers that satisfy their organizations’ security requirements. Web server administrators managing existing Web servers should confirm that their systems address the issues discussed.

therefore, this section includes the generic procedures common in securing most OSs. Security configuration guides and checklists for many OSs are publicly available.

In addition, many organizations maintain their own guidelines specific to their requirements. Some automated tools also exist for hardening OSs, and their use is strongly recommended.

Once an OS is installed, applying needed patches or upgrades to correct for known vulnerabilities is essential. Any known vulnerabilities an OS has should be corrected before using it to host a Web server or otherwise exposing it to untrusted users.

Administrators should ensure that Web servers, particularly new ones, are adequately protected during the patching process. For example, a Web server that is not fully patched or not configured securely could be compromised by threats if it is publicly accessible while it is being patched.

Administrators should generally not apply patches to Web servers without first testing them on another identically configured system because patches can inadvertently cause unexpected problems with proper system operation. Although administrators can configure Web servers to download patches automatically, the servers should not be configured to install them automatically so that they can first be tested.

When configuring the OS, disable everything except that which is expressly permitted—that is, disable all services and applications, reenable only those required by the Web server, and then remove the unneeded services and applications. If possible, install the minimal OS configuration and then add or remove services and applications as needed.

Furthermore, many uninstall scripts or programs are far from perfect in completely removing all components of a service. therefore, it is always better not to install unnecessary services.

Removing unnecessary services and applications is preferable to simply disabling them through configuration settings because attacks that attempt to alter settings and activate a disabled service cannot succeed when the functional components are completely removed. Disabled services could also be enabled inadvertently through human error.

Organizations should determine the services to be enabled on a Web server. Services in addition to the Web server service that might be installed include database access protocols, file transfer protocols, and remote administration services.

Whether the risks outweigh the benefits is a decision for each organization to make. For Web servers, the authorized users who can configure the OS are limited to a small number of designated Web server administrators and Webmasters.

To enforce policy restrictions, if required, the Web server administrator should configure the OS to authenticate a prospective user by requiring proof that the user is authorized for such access. Even though a Web server may allow unauthenticated access to most of its services, administrative and other types of specialized access should be limited to specific individuals and groups.

Although not normally the case for public Web servers, in special situations, such as high-value/high-risk sites, organizations may also use authentication hardware, such as tokens or one-time password devices.

For default accounts that need to be retained, change the names (where possible and particularly for administrator or root level accounts) and passwords to be consistent with the organizational password policy. Default account names and passwords are commonly known in the attacker community.

Implementing this recommendation can help prevent some kinds of attacks, but it can also allow an attacker to use failed login attempts to prevent user access, resulting in a DoS condition. The risk of DoS from account lockout is much greater if an attacker knows or can surmise a pattern to your naming convention that allows them to guess account names.

Note that all failed login attempts, whether via the network or console, should be logged. If remote administration is not to be implemented, disable the ability for the administrator or root level accounts to log in from the network.

However, passwords are economical and appropriate if properly protected while in transit. Organizations should implement authentication and encryption technologies, such as Secure Sockets Layer (SSL)/Transport Layer Security (TLS), Secure Shell (SSH), or virtual private networking (VPN), to protect passwords during transmission.

All commonly used modern server OSs provide the capability to specify access privileges individually for files, directories, devices, and other computational resources. By carefully setting access controls and denying personnel unauthorized access, the Web server administrator can reduce intentional and unintentional security breaches.

Limiting the execution privilege of most system-related tools to authorized system administrators can prevent users from making configuration changes that could reduce security. It also can restrict the attacker’s ability to use those tools to attack the system or other systems on the network.

In such cases, administrators need to select, install, and configure additional software to provide the missing controls. Commonly needed controls include the following:

For example, file integrity checking software can identify changes to critical system files. When planning security controls, Web server administrators should consider the resources that the security controls will consume.

Periodic security testing of the OS is a vital way to identify vulnerabilities and to ensure that the existing security precautions are effective. Common methods for testing OSs include vulnerability scanning and penetration testing.

When you open an HTML file directly from your computer in a web browser, the resulting page may not always look right. The web browser will sometimes require your files to be hosted through an HTTP server, or else it won’t be able to find and interpret them correctly.

So far, you’ve been communicating with your HTTP server using an unencrypted connection. That’s fine for testing or learning how the HTTP protocol works by observing the raw requests and responses in plain text.

To understand this process a bit more, you can experiment with making HTTP requests manually. For example, you can use a command-line program like netcat or a Telnet client, such as PuTTY on Windows, to connect to a running HTTP server and issue HTTP requests, typing them by hand:

What comes next is the server’s response, which starts from the status line followed by a few headers. By inspecting one of the response headers, you can tell that you’ve connected to a Python http.server.

However, the Content-Length header field reveals the size of the resource that you asked about, which is 5,163 bytes long. Note: Because HTTP is a stateless protocol, the server closes the connection as soon it sends a response to the client.

This is known as a persistent connection. Today, most online services don’t support pure HTTP anymore due to security concerns.

In such a case, you’ll typically receive an HTTP 3xx status code along with a Location header pointing to the desired address: Here, you can see that the Real Python website wants you to access it using the secure HTTPS protocol.

Note: While 443 is the standard port number for HTTPS connections, it’s not enough to replace port 80 in the telnet command. You need a different program, like an OpenSSL client, that’s capable of establishing secure connections and using encryption:

You’ll also be able to see the server’s X.509 digital certificate that verifies the server’s identity. Unfortunately, the http.server module built into Python doesn’t support the HTTPS protocol out of the box.

You can do so by using the ssl module from Python’s standard library. Remember that starting a web server on the default port, 443, will require administrative privileges.

Moreover, you’ll need to obtain a valid certificate from a trusted certificate authority (CA), which generally requires purchasing and renewing the certificate after a certain period. Some well-known certificate authorities, such as Let’s Encrypt, are nonprofit organizations that can provide you with a certificate at no charge.