Some Security Measures to Protect Your Servers

Introduction

External and internal attackers day after day are menacing your networks. Many intelligent methods are discovered in order to get access and damage your server. Currently, the Sun Java system application server can’t be as beneficial as it was previously since the tactics used by those attackers are being more dangerous nowadays.

So you need to have a background knowledge of some basic security practices to more protect your server and your personal information. So we will list the most important steps to follow to strengthen your security.

SSH Keys

SSH keys are a pair of cryptographic keys that can be used to authenticate to an SSH server as an alternative to password-based logins. A private and public key pair are created prior to authentication. The private key is kept secret and secure by the user, while the public key can be shared with anyone.

To configure the SSH key authentication, you must place the user’s public key on the server in a special directory. When the user connects to the server, the server will ask for proof that the client has the associated private key. The SSH client will use the private key to respond in a way that proves ownership of the private key. The server will then let the client connect without a password.

How Do They Enhance Security?

With SSH, any kind of authentication, including password authentication, is completely encrypted. However, when password-based logins are allowed, malicious users can repeatedly attempt to access the server. With modern computing power, it is possible to gain entry to a server by automating these attempts and trying combination after combination until the right password is found.

Setting up SSH key authentication allows you to disable password-based authentication. SSH keys generally have many more bits of data than a password, meaning that there are significantly more possible combinations that an attacker would have to run through. Many SSH key algorithms are considered uncrackable by modern computing hardware simply because they would require too much time to run through possible matches.

Firewalls

A firewall is a piece of software (or hardware) that controls what services are exposed to the network. This means blocking or restricting access to every port except for those that should be publicly available.

On a typical server, a number services may be running by default. These can be categorized into the following groups:

• Public services that can be accesses by anyone on the internet, often anonymously. A good example of this is a web server that might allow access to your site.
• Private services that should only be accessed by a select group of authorized accounts or from certain locations. An example of this may be a database control panel.
• Internal services that should be accessible only from within the server itself, without exposing the service to the outside world. For example, this may be a database that only accepts local connections.

Firewalls can ensure that access to your software is restricted according to the categories above. Public services can be left open and available to everyone and private services can be restricted based on different criteria. Internal services can be made completely inaccessible to the outside world. For ports that are not being used, access is blocked entirely in most configurations.

How Do They Enhance Security?

Firewalls are an essential part of any server configuration. Even if your services themselves implement security features or are restricted to the interfaces you’d like them to run on, a firewall serves as an extra layer of protection.

A properly configured firewall will restrict access to everything except the specific services you need to remain open. Exposing only a few pieces of software reduces the attack surface of your server, limiting the components that are vulnerable to exploitation.

VPNs and Private Networking

Private networks are networks that are only available to certain servers or users. For instance, in DigitalOcean, private networking is available in some regions as a data-center wide network.

A VPN, or virtual private network, is a way to create secure connections between remote computers and present the connection as if it were a local private network. This provides a way to configure your services as if they were on a private network and connect remote servers over secure connections.

How Do They Enhance Security?

Utilizing private instead of public networking for internal communication is almost always preferable given the choice between the two. However, since other users within the data center are able to access the same network, you still must implement additional measures to secure communication between your servers.

Using a VPN is, effectively, a way to map out a private network that only your servers can see. Communication will be fully private and secure. Other applications can be configured to pass their traffic over the virtual interface that the VPN software exposes. This way, only services that are meant to be consumable by clients on the public internet need to be exposed on the public network.

Public Key Infrastructure and SSL/TLS Encryption

Public key infrastructure, or PKI, refers to a system that is designed to create, manage, and validate certificates for identifying individuals and encrypting communication. SSL or TLS certificates can be used to authenticate different entities to one another. After authentication, they can also be used to established encrypted communication.

How Do They Enhance Security?

Establishing a certificate authority and managing certificates for your servers allows each entity within your infrastructure to validate the other members identity and encrypt their traffic. This can prevent man-in-the-middle attacks where an attacker imitates a server in your infrastructure to intercept traffic.

Each server can be configured to trust a centralized certificate authority. Afterwards, any certificate that the authority signs can be implicitly trusted. If the applications and protocols you are using to communicate support TLS/SSL encryption, this is a way of encrypting your system without the overhead of a VPN tunnel (which also often uses SSL internally).

Isolated Execution Environments

Isolating execution environments refers to any method in which individual components are run within their own dedicated space.

This can mean separating out your discrete application components to their own servers or may refer to configuring your services to operate in chroot environments or containers. The level of isolation depends heavily on your application’s requirements and the realities of your infrastructure.

How Do They Enhance Security?

Isolating your processes into individual execution environments increases your ability to isolate any security problems that may arise. Similar to how bulkheads and compartments can help contain hull breaches in ships, separating your individual components can limit the access that an intruder has to other pieces of your infrastructure.

Conclusion

In this article, different methods were outlined above, which aren’t the all existed ones nowadays, just some of them to help you improve the security of your systems. But if you have heard somewhere about other tool, you think that it is also important so please share this information with your fellow readers by leaving a comment to make our work more helpful. Of course we can add this to the description made in our article.