What Is SASE (Secure Access Service Edge)?

Traditionally, users connect to a network within the perimeter of their desks, but the global move towards a home workforce has shifted the face of IT and cybersecurity. Secure Access Service Edge (SASE) is an emerging technology that combines traditional IT infrastructure and cloud services to support a range of users and their locations. Instead of requiring users to authenticate into multiple platforms individually, SASE provides users access to all cloud services via data centres. These data centres provide access controls where administrators can manage users and cloud resources.

In a traditional WAN (Wide Area Network), administrators created point solutions across different locations. Each WAN segment had its own firewalls, network components, and user management. Each segment came together in a centralised control segment where servers and other access management could be set up.

In a SASE design, these point solutions are moved to data centres, no longer requiring administrators to manage physical devices. The cloud provider offers firewalls and access management tools, so administrators have reduced overhead. Administrators still need to manage the cloud services, but the cloud provider manages the physical hardware.

Users connect to the network, but instead of using individual WAN devices, they connect to data centres where the business network is located. Administrators can monitor and control all services in the cloud and authorise users to access them instead of managing different services across the Internet.

When IT infrastructure changes, security must be designed around it to ensure the safety of applications and corporate data. The SASE security model attempts to solve cybersecurity issues surrounding traditional WAN architecture and any new cloud resources provisioned for the new environment.

The networking and security components used in a SASE model are mostly newer technology yet designed to work with WANs integrated into the cloud. Adding SASE functionality is necessary for a stable user environment. The technology used in the SASE model includes:

• SD-WAN: A software-defined SD-WAN connects all remote users and manages their private network. The SD-WAN connects users to data centres. Cloud service providers usually provide these data centres with multiple points of presence (PoP) locations. The user’s location determines which data centre (or the group of data centres) the user connects to. By connecting users to data centres near their location, performance is improved. Latency decreases because network traffic travels across data centres instead of the Internet.
• Zero trust: In a traditional environment, companies inherently trusted users connected to the network. However, insider threats have become a real concern for corporations where users intentionally or unintentionally install malware or disclose data to attackers. Therefore, a zero-trust policy inside a WAN is essential. In a SASE security model, zero-trust is implemented across all network segments and data access where the standards of least privilege for authorisation are practised.
• Cloud services: Implementing cloud services isn’t new to networking, but in a SASE model, users don’t connect directly to the cloud service from their work computers. Instead, they connect to the corporate network at cloud data centers and use corporate network resources to connect to applications. This gives administrators the ability to monitor access and centralize access controls.
• Identity access management (IAM): By forcing users to connect to the network before accessing cloud resources, administrators can control access using identity management instead of IP addresses. Administrators can add users to groups and authorize access to groups. Organizing authorization by groups makes it easier for administrators to manage access across several resources and revoke privileges when necessary.

SASE delivers an advanced approach to network security that is becoming increasingly vital in today’s vulnerable landscape. With SASE, organisations can securely connect users to any application to provide the best user experience while securing the network and cloud-based resources from any location and device.

SASE incorporates SD-WAN and cloud security architectures, providing a secure and direct user access path that reduces latency. This is achieved by securing DIA (Direct Internet Access), which is the most direct user access path, preventing malicious traffic and intervening before it reaches the enterprise. SASE can also mitigate DDoS attacks and enable a full security stack anywhere in the network.

SASE serves as a framework for a network architecture that brings cloud-native security technologies, including SWG (Secure Web Gateway), CASB (Cloud Access Security Broker), ZTNA (Zero Trust Network Access), and FWaaS (Firewall-as-a-Service), into one platform. This integration enables a full range of security capabilities to enhance visibility and control.

SASE also helps simplify network security by consolidating multiple security functions into a unified platform, reducing complexity and cost. By streamlining security protocols, organisations can easily manage their networks, improve security posture, and reduce the risk of cyber threats. It’s become an integral tool for organisations that want a secure network and cloud-based resources while ensuring optimal user experience.

A change in IT infrastructure means an upfront cost, so organisations want to know the benefits before they dive into restructuring the network. Despite its upfront costs, SASE inevitably saves money and provides several other advantages organisations can leverage:

Reduced Costs

Instead of managing and buying multiple point products to service and secure different WAN segments, the organisation can reduce costs using data centre resources and a centralised management system.

Improved Performance

The business network within data centres has its own network backbone and infrastructure. Users connect to a data centre near their location, so network latency is reduced.

Reduced Complexity

With traditional infrastructure, IT must manage every component across WAN segments. With SASE, the network is in the data centre’s cloud, reducing the components administrators manage and network complexity.

Threat Prevention

SASE architecture provides comprehensive security features, such as application and resource cloaking, segmentation, and user/device/location-based risk assessment (UEBA). Its inline encryption/decryption, distributed control, and data planes ensure all connections are inspected and secured.

Consistent Policy

SASE architecture delivers comprehensive UTM services, applies consistent policy enforcement, and dynamically enables connections based on authentication, identity, and business rules, providing a secure, consistent client-to-cloud user experience.

New Business Scenarios

SASE utilises secure access regardless of location, enabling secure work from anywhere, seamless SaaS adoption, and flexible multi-cloud environments. Their scalable, cloud-centred, and cost-effective architecture eliminates bottlenecks and supports growth.

Better IAM

Instead of managing IP addresses, administrators manage users and user groups. This centralised and organised IAM provides improved security and access controls.

Because SASE is a new network architecture methodology, some administrators fear its drawbacks. Chasing the latest technology or processes can be expensive, especially if they aren’t a better alternative or save the organisation money. The wrong technology can be disastrous for IT and complicate how systems are managed.

The SASE disadvantages are few, but administrators might recognise some challenges:

• A single point of failure: If not appropriately configured, a SASE can be a single point of failure, especially for remote users. Users who cannot connect to the local network cannot access necessary productivity tools or services.
• Relying on a single cloud provider: Once the network relies on cloud data centres, the organisation is locked into a single provider. Any price changes or changes to the cloud provider’s architecture affect the business and could force administrators to change the network’s configuration.
• Adoption and integration: While SASE can offer many benefits, organisations that have not yet fully embraced cloud adoption may find it challenging to converge network security and access into a single model, potentially leading to drawbacks.
• Maintaining business continuity: The SASE ecosystem can be segmented and complex, making key processes like change management and procurement challenging for organisations looking to implement the technology.
• Network cohesion: Selecting the right SASE partner and ensuring coordination between networking and security professionals can be challenging, as organisations must carefully consider their options and work collaboratively to achieve a successful deployment.

These challenges can be overcome using a multi-cloud design where one provider can be used as a failover, and another supports daily productivity. However, this method is also expensive. Organisations with several remote users and cloud resources can best benefit from SASE, even with its challenges. The costs associated with a catastrophic failure will far surpass the cost of failover.

Leveraging a SASE framework can streamline network functions, reduce costs, and enhance overall performance, but choosing the right vendor is crucial to unlocking its potential. Here are some key criteria to consider when selecting a SASE vendor.

• Cloud-native approach: Ensure the SASE vendor has a converged cloud-native software stack in their model. This covers on-site, mobile, and cloud-based network edges, as SD-WAN appliances and other point solutions cannot.
• Dynamic network support: With dynamic network conditions between remote branches or users/devices and cloud gateways, prioritise application-aware connectivity, which supports an optimal user experience.
• Integration: Choose a SASE vendor that offers Zero Trust Network Access (ZTNA) integration, which grants network access based on applications and user identities, enabling a contextually aware approach to network security.
• Comprehensive toolkit: Seek out experienced vendors that offer a complete solution, including SD-WAN, FWaaS, ZTNA, CASB, SWG, DLP, sensitive data, malware inspection, and user entity behaviour analytics.
• Network scalability: Look for a SASE vendor that provides a global service level agreement (SLA) backed private backbone, ensuring that enterprises have excellent network performance on a wide scale.
• Interface: Certain vendors offer an easy-to-use interface, streamlining day-to-day network security and management, allowing IT professionals to focus more on business functions and troubleshooting errors.
• Unified configuration: Partner with a SASE vendor that provides single-pane-of-glass management for unifying user, device, network, and security policy definition and management to deliver real-time and historical insights with AI-based tools for efficient correlation and troubleshooting.