In short
Security Service Edge (SSE) suits organisations whose staff mostly work away from the office; SASE suits multi-site organisations changing their WAN too. A Security Service Edge is cloud-delivered security: secure web gateway, CASB and ZTNA, usually with firewall as a service and DLP. SASE adds SD-WAN, so offices and remote users share one policy.
Want an impartial recommendation?
Tell us about your users, systems and priorities and we will tell you which option fits, and why.
Security Service Edge (SSE) and SASE in plain terms
A Security Service Edge (SSE) moves the security checks that used to happen on an office firewall or web proxy into a provider's cloud. A user's device connects to the provider's nearest point of presence, and policy is applied there: which websites and SaaS applications they may use, what data may leave, and which of your private applications they may reach. It protects people, wherever they are.
A secure access service edge (SASE) is a Security Service Edge plus the network. SD-WAN appliances or software at each office choose the best path across leased lines (opens in a new tab), broadband and mobile links, and send office traffic into the same security cloud over tunnels. It protects people and sites under one policy.
So the short answer to "SASE vs Security Service Edge (SSE)" is that the Security Service Edge is a subset of SASE. Every SASE platform contains a Security Service Edge; not every Security Service Edge comes with SD-WAN. For the category as a whole, see what is SASE, and for the security half on its own, our Security Service Edge (SSE) guide.
Security Service Edge (SSE) vs SASE: components compared
| Component | What it does | Security Service Edge (SSE) | SASE |
|---|---|---|---|
| Zero trust network access (ZTNA) | Per-application access to private apps after identity, device and context checks | Yes | Yes |
| Secure web gateway (SWG) | Filters web traffic, blocks malicious sites and scans downloads | Yes | Yes |
| Cloud access security broker (CASB) | Discovers and controls SaaS use, inline or through API connections | Yes | Yes |
| Firewall as a service (FWaaS) | Layer 3 to 7 firewall policy applied in the cloud | Usually | Usually |
| Data loss prevention (DLP) | Stops sensitive data leaving through web, SaaS and AI tools | Usually, by tier | Usually, by tier |
| Remote browser isolation (RBI) | Renders risky sites away from the device | Often, by tier | Often, by tier |
| DNS-layer security | Blocks known-bad domains before a connection is made | Often | Often |
| SD-WAN | Path selection and failover across WAN links at each site | Not included | Yes |
| Branch tunnels into the security cloud | IPsec or automated tunnels from offices | Often supported | Built in with the vendor's SD-WAN |
In a Security Service Edge (SSE) vs SASE comparison, SD-WAN is the one line that always differs. The labels are marketing categories, not standards, so vendors draw the other lines in slightly different places. Compare the components you need rather than the badge on the box. Our Cloud Security site covers two of the building blocks in depth: CASB (opens in a new tab) and the secure web gateway (opens in a new tab).
Still not sure which way to go? Ask us
Tell us what matters most to you and we will recommend one, with the trade-offs explained.
SASE vs Security Service Edge (SSE) vs ZTNA
People often meet these three terms in the same week. They nest:
- ZTNA controls access to your private applications.
- Security Service Edge (SSE) adds protection for traffic to everyone else's applications: the web, SaaS and generative AI services.
- SASE adds the network that connects branch offices to that security.
If remote staff send all their internet traffic back through the office over a VPN so the office firewall can filter it, replacing the VPN with ZTNA alone leaves their web traffic unprotected. That is the usual reason a ZTNA project becomes a Security Service Edge (SSE) project. Our ZTNA vs SASE page covers that decision, and ztna.org.uk explains how ZTNA works (opens in a new tab) in detail.
Who needs Security Service Edge (SSE) and who needs SASE?
| Your situation | Usually fits | Why |
|---|---|---|
| Most staff work remotely or hybrid, apps are mainly SaaS, one or two offices | Security Service Edge (SSE) | The people are the perimeter; office networking is not the problem |
| A remote access VPN is the main pain point | Security Service Edge (SSE), or ZTNA first | Private access and web protection replace the VPN and the backhaul |
| Several branches on MPLS or ageing routers, renewals due | SASE | SD-WAN and security can be replaced and managed together |
| Branches already on an SD-WAN you are happy with | Security Service Edge (SSE) plus your SD-WAN (dual-vendor SASE) | Keep the WAN investment; tunnel sites into the Security Service Edge |
| Retail, education or multi-site estates with lots of on-site devices | SASE, with local firewalls where needed | Sites carry traffic that does not involve a remote user |
A common route is to start with a Security Service Edge (SSE) while the WAN contract still has time to run, then move to full SASE at the next refresh. That is a sensible order, provided the Security Service Edge you choose can take branch tunnels or integrates with SD-WAN later. The networking side is covered on SASE vs SD-WAN.
Weighing up the options?
We can compare them against your own requirements and recommend what fits.
Single-vendor or dual-vendor SASE
SASE can be bought two ways.
- Single-vendor SASE: one supplier provides the Security Service Edge (SSE) and the SD-WAN. You get one policy model, automated tunnels between sites and the security cloud, and one support route.
- Dual-vendor (or multi-vendor) SASE: a Security Service Edge (SSE) from one supplier paired with SD-WAN from another, joined by IPsec tunnels or a documented integration. You keep networking kit you already own, with two consoles to run.
Neither is wrong. Single-vendor suits new builds and estates already standardised on one vendor; dual-vendor suits organisations part-way through a WAN contract or with an SD-WAN they want to keep. The trade-offs are set out on single vendor SASE. The NCSC's advice on assessing ZTNA services and providers (opens in a new tab) applies to both: understand which functions you are delegating to the provider, how critical the service becomes and what visibility you keep over policy and logs.
How the platforms we supply map to Security Service Edge (SSE) and SASE
| Platform | Security Service Edge (SSE) side | SASE (networking) side |
|---|---|---|
| Cisco SASE | Cisco Secure Access (opens in a new tab), which Cisco calls its cloud-delivered security service edge: ZTNA, internet and SaaS protection, plus VPN as a service for apps that are not ZTNA-ready | Cisco SD-WAN or Meraki SD-WAN; Cisco also publishes a guide for third-party SD-WAN such as HPE Aruba Networking EdgeConnect |
| Check Point SASE (formerly Harmony SASE (opens in a new tab)) | Internet Access, Private Access and SaaS Security | SD-WAN in the same platform, which Check Point describes as a single-vendor SASE solution |
| HPE Aruba Networking SASE | HPE's Security Service Edge (SSE) service | HPE Networking (opens in a new tab) EdgeConnect SD-WAN, which HPE positions as the foundation for a unified SASE architecture |
| Barracuda SecureEdge | ZTNA, firewall as a service and web security | Secure SD-WAN in the same platform |
| Exium SASE (now part of NETGEAR) | Secure Internet Access and Secure Private Access | Cyber Gateway: software next-generation firewall with SD-WAN, licensed per site |
| Todyl SASE | ZTNA, secure web gateway, secure DNS and a next-generation firewall with SSL inspection, through its agent | SASE Tunnel for IPsec connections from an existing site edge |
| WatchGuard SASE | FireCloud Total Access: firewall as a service, secure web gateway and ZTNA | Firebox appliances provide SD-WAN at sites |
| Trend Micro ZTSA (opens in a new tab) | Private Access, Internet Access with CASB controls, AI Secure Access | Pair with your existing WAN; ask us |
Sources: Cisco SASE (opens in a new tab), Cisco Secure Access (opens in a new tab) and Cisco's EdgeConnect integration guide (opens in a new tab), Check Point SASE (opens in a new tab), HPE Networking EdgeConnect (opens in a new tab), Barracuda SecureEdge (opens in a new tab), Todyl SASE (opens in a new tab) and WatchGuard's FireCloud Total Access announcement (opens in a new tab), checked 9 November 2026. Every platform is compared on SASE vendors.
What the NCSC says about Security Service Edge (SSE) and SASE
The NCSC's signals and policy engines (opens in a new tab) guidance groups Security Service Edge (SSE) and SASE with VPN-as-a-service as network-level policy engines: they decide which network destinations a client can reach and tell an enforcement point, such as a connector or proxy, to forward the traffic. It contrasts these with application-level policy engines built into applications or identity platforms. Many organisations use both. (The NCSC writes "Secure Service Edge"; it is the same thing as Security Service Edge.)
The same guidance carries a warning that matters more than the label. Its first ZTNA anti-pattern (opens in a new tab) is deploying a Security Service Edge (SSE) or SASE as a direct replacement for a VPN while keeping the old access model, where users authenticate once and then reach most of the internal network. That recreates the "walled garden". Buying a Security Service Edge or SASE is the start; per-application policy, segmentation and removing old access routes are what change the risk. Per-application policy design is covered in depth on ztna.org.uk.
How Forever Systems helps
We supply Security Service Edge (SSE) and full SASE platforms from several vendors, so we can recommend the one that fits. We can map your users, applications, sites and WAN contracts, show whether a Security Service Edge covers what you need now or whether SD-WAN belongs in the same project, and, where the vendor offers a trial, set up a pilot with a small group before you commit. Subscriptions can be billed monthly, terms confirmed at quote, and scope and timescales are confirmed at quote too. Pricing depends on users, components and sites, so ask us for a quote. Contact us to talk it through.
How Forever Systems helps with SASE
Forever Systems supplies several SASE and Security Service Edge (SSE) platforms, so we can recommend the one that fits your sites, your people and the network and security kit you already run.
- Assess first: we look at your current VPN, firewalls, WAN links and identity set-up, and the applications people need to reach
- Help you choose: single-vendor or dual-vendor SASE, or Security Service Edge (SSE) first and SD-WAN later, matched to what you need now
- Pilots and phased roll-out: we can help you start with one group of users or one site, then extend policy step by step
- Licensing in one place: subscriptions can be billed monthly, with terms confirmed at quote
We work with businesses, schools, charities and public sector organisations. Pricing depends on users, sites, components and term, so ask us for a quote.
Frequently asked questions
Is Security Service Edge (SSE) part of SASE?
Yes. Security Service Edge (SSE) is the security half of SASE: secure web gateway, CASB and ZTNA, usually with firewall as a service and DLP. SASE adds SD-WAN networking so branch offices use the same security cloud and policy.
What is the difference between Security Service Edge (SSE) and ZTNA?
ZTNA controls access to your private applications. Security Service Edge (SSE) includes ZTNA and adds protection for internet, SaaS and AI use, such as a secure web gateway, CASB and data loss prevention.
Do I need SD-WAN to have SASE?
By definition SASE includes SD-WAN or equivalent branch networking. Without it you have a Security Service Edge (SSE), which may be all you need if most of your staff work remotely and your offices are simple.
Can I start with Security Service Edge (SSE) and move to SASE later?
Yes, and many organisations do. Choose a Security Service Edge (SSE) that accepts branch tunnels or integrates with SD-WAN, then add the networking when routers or WAN contracts come up for renewal.
Is Cisco Secure Access a Security Service Edge (SSE) or SASE?
Cisco describes Secure Access as its cloud-delivered Security Service Edge (SSE). Cisco SASE combines Secure Access with Cisco SD-WAN or Meraki SD-WAN, and Cisco publishes a guide for using Secure Access with third-party SD-WAN such as HPE Aruba Networking EdgeConnect.
Still deciding?
Ask us and a member of our team will get back to you.