What is a Virtual Private Cloud? Understanding key components and architecture

Cloud computing has revolutionized business networks, cutting the need for hardware and maintenance tasks while making network design more flexible than ever.

On the other hand, the public cloud can feel a little exposed. Sharing space with other users increases security risks - and those risks may be unacceptable when storing or processing client data.

Virtual Private Cloud (VPC) deployments offer a practical solution.

VPCs create private zones within the public cloud, blending the pros of cloud computing with robust security. Even so, using VPCs safely is essential. Let's explore the subject and understand how private cloud technology can work for you.

What is Virtual Private Cloud infrastructure?

A Virtual Private Cloud is a private virtualized domain within the public cloud. VPCs contrast with public cloud computing, where tenants share cloud space with other users. VPC deployments use single-tenant architecture, creating private spaces within the public cloud.

VPCs allow companies to benefit from cloud computing's flexibility and easy scaling while securing critical resources via logical isolation.

How does a Virtual Private Cloud work?

Unlike public cloud solutions, VPC cloud infrastructure is owned and maintained by the organization that uses it.

A VPC resides in a standard public cloud data center. Owners source software and cloud hosting facilities and may hire additional IT management professionals. However, the VPC is effectively private. Isolation minimizes links to other publicly hosted assets.

Technicians use logical isolation to separate VPC resources from the public cloud. This technique uses Virtual Local Area Networking (VLAN) technology and private IP subnets to create barriers and protect private assets.

Private subnets make local IP addresses inaccessible from the public internet. VLANs isolate types of traffic, prevent access from unauthorized devices, and ensure all traffic relates to the VPC owner.

Most VPC instances also use Virtual Private Network coverage (VPNs). A VPN connection creates an encrypted zone around the shared public cloud. Users log into the VPC via their VPN gateway. The VPN conceals their identities and activity when using the Virtual Private Cloud.

VPC components and architecture

VPC networks tend to have elements in common. As the VPC diagram below shows, core components include:

• Web gateways: These create a connection between the VPC environment and the public cloud or the Internet. Each VPC requires a separate internet gateway, which serves as a location for access control measures. Best practices advise users to guard every web gateway with a VPN.
• NAT gateways: One-way gateways that enable outward connections from the VPC to the public internet.
• Subnets: A subnet is a group of IP addresses linking assets within your VPC. VPC subnets can be public or private. Public subnets define resources users can connect with inside the internet gateway. Private cloud subnets are off-limits to public web users and connect to the NAT gateway.
• Routers and route tables: Route tables define the movement of VPC network traffic. Routers use route tables to direct traffic to apps or data containers. Without a properly configured route table, elements of the VPC cannot communicate.
• Security groups: VPC security groups operate like firewall rules at the instance level, regulating traffic between the private and public cloud.
• Network access control lists (NACLs) provide security at the subnet level. They set rules for traffic that enters or leaves a subnet and block unauthorized users.
• VPC peering: Sometimes, users need to connect resources on different Virtual Private Clouds. Peering uses IPv4 or IPv6 addresses to safely link VPC resources and ensure smooth data flows.

Benefits of using a Virtual Private Cloud

There are many reasons to deploy a VPC instead of relying on public cloud infrastructure or locally-hosted network resources. For instance, Virtual Private Cloud benefits include:

• Easy scaling: Users can add VPC capacity as needed. They don't need to install hardware or software solutions; they can purchase cloud space from vendors when needed.
• Improved performance: Well-designed VPCs generally perform better than equivalent on-premises networks or public cloud resources.
• Flexibility: Users can connect VPC infrastructure to the public cloud or on-premises assets. They can accommodate remote working arrangements and communicate across geographical regions without relying on public internet connections.
• Security: VPCs provide secure work and data storage environments, provided cloud vendors update their infrastructure regularly. Logical isolation also makes VPCs more secure than relying on public cloud computing.
• Value for money: Deploying a Virtual Private Cloud is cost-effective. Installation requires little human labor, and you can often rely on off-the-shelf solutions. Hardware overheads are low, while your cloud vendor should handle most maintenance needs.

Security challenges associated with using VPCs

One of the main benefits of virtual private cloud systems is that VPC deployments are usually more secure than public cloud alternatives and traditional networking.

However, using VPC in cloud infrastructure can create security vulnerabilities. Users should understand the risks before permanently moving assets to private cloud services.

1. Improper configuration allows paths from the public internet

Generally, attackers find it difficult to hop from a public cloud provider to private cloud assets. Isolation by VLANs and subnets minimizes the risk of unauthorized infiltration.

However, default subnet configurations can leave open routes to and from the external internet. Administrators may also fail to secure subnets via network access control lists. Hence, VPC best practices always include changing default configurations to reflect your cloud architecture.

Adding access control lists is also recommended. The absence of ACLs makes it easier for attackers to access subnets that should be restricted within the VPC.

2. Preventing lateral movement within the VPC

Malicious actors accessing VPC infrastructure can move between peered resources and seek compromised applications or storage containers. For instance, infrequently updated security rules may not cover virtual machines, raising the risk of data breach attacks.

Similarly, access control lists and subnets can become misaligned, enabling lateral access to resources that should be off-limits.

3. Ensuring secure access

The issues above are important, but unauthorized access is the most significant VPC cybersecurity risk.

Problems often arise when cyber attackers obtain credentials or breach firewall protection. Insecure service endpoints may enable easy access to the entire deployment. Weak access controls and privileges management can allow excessive access - exposing customer records or financial data.

When that happens, attackers can roam freely within a virtual private cloud and cause chaos. So, how should you secure access to your VPC and prevent unauthorized intrusions?

VPN coverage is essential. Site-to-site VPNs create secure connections between offices or remote work locations and your VPC gateway. When users log in, the VPN shields their activity, making credential theft attacks much less likely.

NordLayer enables users to connect directly to AWS or another cloud provider via a dedicated VPN. We recommend adding this security feature to ensure watertight private cloud security.

Major Virtual Private Cloud providers

VPCs are not mom-and-pop operations. Big global corporations usually host virtual cloud infrastructure and offer diverse products to suit client needs. Let's run through popular cloud provider options before exploring how to perfect your VPC setup.

• Amazon Web Services (AWS). AWS is the market leader in VPC services, claiming around 32% of all cloud hosting revenues. Users can rent virtual machines via the Amazon Elastic Compute Cloud (EC2) and use Amazon Relational Database Service (RDS) to manage databases in the cloud. Basic VPC is free, but extra costs apply for services like NAT gateways.
• IBM Cloud. IBM's VPC offering uses a Software-Defined Network (SDN) model to deliver VPC solutions. Users mix and match computing, storage, and networking architecture. Pay-as-you-use billing allows flexibility and cost-effective scaling.
• Google Cloud. Google's VPC is similarly flexible and covers every geographical region. Features include flow logs, peering, central firewall management, and free credits to get smaller businesses started.
• Microsoft Azure. Azure is Amazon AWS' main competitor. Microsoft's VPC includes a built-in IPSec VPN, granular controls over communication between subnets, and peering and NAT gateways for maximum flexibility.

Securing access to a VPC with NordLayer

If you decide to use a VPC, you must also implement the right security options to safeguard your data and applications. NordLayer is compatible with the most popular VPC solutions and can enhance your security by protecting who can access the information stored there.

To secure your VPC, consider implementing the following measures:

• Secure remote access: Users need secure access to resources and applications inside the VPC. NordLayer’s Site-to-Site VPN provides an encrypted tunnel. This allows secure access to the VPC without exposing data to public internet threats.
• Preventing unauthorized access: NordLayer’s Cloud Firewall adds an extra security layer by allowing you to control who can access the VPC. You can restrict VPC access to authorized users, prevent accidental data leaks, and implement multilayered authentication methods with SSO and MFA. That way, you can double or triple-check identities before granting access.
• Device Posture Security: NordLayer’s Device Posture Security ensures that only approved devices that meet company security policies can connect to the VPC. This reduces the risk of compromised or non-compliant devices accessing sensitive data.

NordLayer’s powerful suite of security tools makes it easy to protect your VPV and ensure that only the right users and the right devices can access your resources. We can help you benefit from VPC architecture without putting critical information at risk. To find out more, contact the NordLayer team today.