What is Zscaler, How it Works, and What it Does for IT Leaders

What Is Zscaler?

Zscaler is a cloud-native security platform that delivers protection and access control from the cloud instead of through traditional on‑premises firewalls and VPNs. It sits in the Security Service Edge (SSE) category and is built around Zero Trust principles: no user, device, or app is trusted by default—every request is verified and evaluated in real time.

In practice, Zscaler:

• Sits between your users/devices and the internet, SaaS, and internal apps
• Authenticates identity and inspects traffic in the cloud
• Applies security and data policies inline
• Connects users and workloads only to the specific applications they’re allowed to reach—never to your entire network

It’s used heavily by mid‑ to large‑scale organizations with distributed workforces, significant SaaS and cloud adoption, and strong security or compliance pressure.

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How Does Zscaler Work?

At a high level, Zscaler replaces the “data center as the hub” model with a cloud security fabric called the Zero Trust Exchange. Instead of dragging traffic back to your network, you send it to Zscaler’s globally distributed cloud, where security and access decisions are made.

1. Traffic onboarding

You onboard traffic to Zscaler using:

• A lightweight endpoint agent
• Proxy/PAC settings
• Tunnels from branches or data centers (e.g., SD‑WAN / router integration)

All relevant traffic (internet, SaaS, private app) is steered to the nearest Zscaler data center.

2. Identity and context verification

Zscaler integrates with your identity provider (Azure AD, Okta, Ping, etc.) to check:

• Who the user is (identity, groups, role)
• What device they’re on (managed/unmanaged, OS posture)
• Where they are (location, network)
• When and how they’re accessing (time, behavior patterns, risk signals)

Every connection is evaluated per session, not just at first login.

3. Policy decision

Based on your policies, Zscaler decides, for each request:

• Allow, block, or require step‑up authentication
• Apply specific controls (e.g., DLP, read‑only, watermarking)
• Route via the appropriate path (internet/SaaS vs. private app)

Policies consider identity, device, app, content, and context, not just IP/port.

4. Inline inspection

Zscaler acts as a full proxy:

• Decrypts SSL/TLS where allowed
• Inspects traffic with multiple engines:
  • URL/category filtering
  • Malware detection and sandboxing
  • Command‑and‑control and phishing detection
  • DLP and data classification
• Re‑encrypts and forwards traffic

All of this happens inline in the cloud, close to the user and the destination app.

5. Application‑specific connection

For internet/SaaS:

• Zscaler forwards clean, policy‑compliant traffic to the destination service.

For private apps (ZPA):

• Connectors you deploy inside your environment make inside‑out connections to Zscaler.
• Apps are not exposed on the internet (no inbound ports, no VPN gateways).
• Zscaler brokers a connection from the validated user to the specific app—without ever putting the user “on the network.”

Result: users never gain broad IP‑level reach into your environment; they only gain access to the apps they’re allowed to use.

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What Zscaler Offers to IT Leaders

Zscaler is broad; for IT leaders, it’s helpful to look at what it offers through four lenses:

• Cyberthreat protection
• Data security
• IoT & mobile security
• Zero Trust for branch and cloud

Cyberthreat Protection

IT leaders are constantly balancing innovation against the fear of a breach that defines their career. Zscaler’s cyberthreat protection is designed to reduce that fear in practical ways.

1. Reduce attack surface

• App invisibility: Internal applications aren’t exposed on the public internet; no open inbound ports, no published VPN gateways.
• No network access: Users never join your network; they get brokered, app‑specific connectivity.
• Microsegmentation by design: Lateral movement is dramatically harder because there’s no flat, reachable network from the user’s perspective.

This directly cuts down the avenues for recon, scanning, and lateral movement.

2. Inline threat prevention at cloud scale

Because Zscaler sits inline for user traffic, it can:

• Inspect encrypted traffic without overloading on‑prem appliances
• Block malware, ransomware, phishing, and exploit attempts before they reach users
• Use global threat intelligence (from hundreds of billions of daily transactions) to recognize patterns your local stack might miss

Threat prevention is always on, for:

• Office users
• Remote/hybrid workers
• Branch locations
• Users on untrusted networks

3. Stronger incident detection and response

Zscaler’s logs and analytics help your SOC:

• See web/SaaS/private app activity from a single viewpoint
• Correlate user behavior, threat events, and DLP violations
• Use integrations with SIEM/XDR to enrich investigations

That shortens the “What actually happened?” phase and supports faster, more confident response.

Data Security

Most IT leaders are held personally accountable not just for keeping systems up, but for keeping data in. Zscaler’s data security capabilities are built to enforce your policies wherever data flows.

1. inline DLP across channels

Zscaler can inspect:

• Web traffic (uploads, posts, forms)
• SaaS traffic (file shares, chat, collaboration)
• Private application access
• Email (via integration)

and apply DLP policies in real time, such as:

• Blocking uploads of regulated data (PII, PHI, PCI)
• Preventing copy/paste into unsanctioned destinations
• Warning and coaching users on risky behavior
• Allowing but logging certain flows for audit

2. SaaS and cloud data posture

Through CASB and SaaS security posture controls, Zscaler helps you:

• Discover which SaaS apps are actually in use (sanctioned and shadow IT)
• Classify apps by risk and enforce access policies accordingly
• Check for misconfigurations that could expose data externally
• Apply consistent controls across multiple SaaS providers

3. Compliance‑aligned controls and reporting

Zscaler’s data protection features support common compliance needs by:

• Providing detailed logs of access, violations, and policy actions
• Enforcing location‑ and content‑based restrictions (e.g., EU data residency)
• Supporting reports suitable for auditors and regulators

This shifts you from “we hope our policies are followed” to “we can show how they’re enforced and monitored.”

IoT & Mobile Security

Your risk is no longer just laptops on corporate LANs. You’re dealing with:

• Mobile users on Wi‑Fi you don’t control
• Devices that aren’t full PCs (tablets, phones, scanners, rugged devices)
• IoT/OT systems that often lack modern security controls

Zscaler extends Zero Trust concepts into this territory.

1. Securing mobile users everywhere

With the Zscaler client on mobile devices:

• User traffic is steered to Zscaler regardless of network (home Wi‑Fi, hotel, cellular).
• The same security stack—SWG, CASB, DLP, threat prevention—is applied.
• Policies are user/identity‑centric, not tied to IP or physical location.

This means your mobile workforce gets:

• Consistent protection
• Consistent access experience
• Reduced need for separate mobile gateways/VPN logic

2. Visibility and control for “unmanaged” edges

For devices you can’t or don’t fully manage (e.g., some BYOD, contractor devices, or thin IoT/OT telemetry endpoints), Zscaler can help via:

• Network‑level steering (e.g., via SD‑WAN, router, or Wi‑Fi controller)
• Policy based on source network/zone, app, and content
• Central visibility into which devices/segments are communicating where

This doesn’t magically fix insecure IoT/OT design, but it gives you control points and visibility you’d otherwise lack.

3. IoT/OT access to cloud and internal apps

For IoT/OT devices that need:

• Access to cloud APIs or services
• Access to internal dashboards or control systems

Zero Trust principles mean you can:

• Limit each device or segment to only the minimum necessary destinations
• Apply inline inspection where feasible
• Monitor and log all communications for anomaly detection

Compared to “flat VLAN and ACL” approaches, this is a step toward constrained, observable access for inherently risky device classes.

Zero Trust for Branch and Cloud

For many IT leaders, the biggest structural headache is aligning branches and cloud with a Zero Trust model.

1. Branch transformation

Traditional branch model:

• MPLS or VPN backhaul to data center
• Local or centralized firewalls
• Complex routing and underlay/overlay management

With Zscaler in the mix:

• Branches can use local internet breakouts; traffic is sent to Zscaler instead of your DC.
• You can often reduce or eliminate MPLS for internet/SaaS access.
• Security stack (SWG/CASB/DLP/Threat Protection) is now cloud‑delivered.

Benefits:

• Lower WAN costs (depending on MPLS footprint)
• Better SaaS performance (no hairpinning)
• Uniform security across branches and remote users

2. Zero Trust access to internal apps (ZPA)

Instead of standing up VPN gateways in each DC/region:

• You deploy Zscaler connectors in your data centers or VPCs.
• Apps are published via ZPA, not exposed to the internet or tied to IP ranges.
• Users authenticate to Zscaler and get app‑specific connections.

This works across:

• On‑prem data centers
• Private clouds (AWS, Azure, GCP)
• Partner‑hosted environments

Result: a logical, application‑centric fabric over your hybrid/multi‑cloud footprint without having to tightly mesh all your networks for user access.

3. Multi‑cloud connectivity and workload‑to‑workload

Beyond user access, Zscaler can also support workload‑to‑workload connectivity:

• Microservices in one cloud securely talk to back‑end systems in another
• Policies govern which services can talk to which others (again: app‑centric, not IP‑centric)
• Inspection and logging apply to inter‑service traffic where configured

This helps you progress from:

“Cloud 1 talks to Cloud 2 over a big IP tunnel we hope is locked down”

toward:

“Service A is allowed to talk only to Service B on defined paths, controlled and logged.”

For an IT leader trying to put structure around accelerating cloud sprawl, that’s not trivial.

How IT Leaders Can Explore Zscaler Solutions on TechnologyMatch

Evaluating Zscaler (and its Zero Trust/SSE peers) can be noisy and time‑consuming if you do it through cold outreach and random vendor pitches. TechnologyMatch gives IT leaders a quieter, more controlled way to do this.

Key advantages you get:

• You stay anonymous until you choose otherwise
• Vendors—including Zscaler partners—don’t see your identity or get your contact details until you want to speak to them. That means no spray-and-pray sales spam just because you were curious.
• Matches are curated, not generic
• You describe what you’re solving for (e.g., “VPN replacement for 3,000 users,” “Zero Trust SSE across multi‑cloud, heavy SaaS”), and TechnologyMatch surfaces a small, vetted set of relevant vendors—Zscaler, where appropriate, plus realistic alternatives.
• You save time on the upfront legwork
• Instead of researching 20 vendors to find 3 worth serious evaluation, you start with a short list that’s already been filtered for fit. Calls you do take are with vendors prepared to focus on your architecture, constraints, and goals.

Here’s what the process would look like on TechnologyMatch:

1. After you signup to TechnologyMatch, search for “Zscaler” on the dashboard.‍

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2. Navigate through the solution providers and their offerings. Accept Match with the potential partner or vendor.‍‍

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3. The new match will show up in the “My Matches” section of your dashboard. You can now message them or schedule a meeting. The meeting then shows up in your calendar.‍‍

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We know how difficult it is to find and work with the right managed service providers in the market today. There’s too much noise and not enough reliable partners. Which is why we built TechnologyMatch:

• Our platform is buyer-first, so potential partners have no way of spamming you with cold outreach.
• Only you can make the first move by messaging them and scheduling calls.
• All your potential partners can be managed and evaluated from a single dashboard, without having to switch platforms or sift through emails.
• You get access to potential partners, resellers, vendors, and solution providers who have been verified through a strict vetting process.