Phishing Attacks Are Hard to Guard Against! The All-Optical Five-Tier Defense System Builds a Robust Corporate Network Barrier

An ordinary-looking email, a login page disguised as a business system, or a message appearing to come from an "acquaintance" can all become the starting point of corporate cybersecurity incidents.

In recent years, phishing attacks have grown increasingly deceptive. Attackers no longer merely send obvious spam emails. Instead, they may impersonate clients, partners, corporate administrators or even internal systems. Using meticulously forged links and webpages, they trick employees into clicking links, downloading files or entering account credentials.

For enterprises, the greatest difficulty in defending against phishing lies in this: the attack entry point is often not a network device, but people.

Firewalls can block some abnormal access attempts. But what if an employee actively clicks a phishing link? What if account passwords have been leaked? What if malware has penetrated the intranet?

This means enterprises cannot rely on a single perimeter defense line to fend off phishing attacks.

A truly effective security system must cover every stage after an attack is launched: blocking risks from entering, controlling unauthorized access, restricting lateral spread, protecting critical business operations, and promptly detecting and tracing abnormal activities.

Combining all-optical networks, secure access, business isolation and unified management capabilities, AINOPOL creates a multi-layered cybersecurity protection framework. Even when facing phishing attacks that cannot be completely avoided, enterprises can limit the impact scope of security incidents as much as possible.

I. Why Phishing Attacks Remain Hard to Prevent

1. Attack methods increasingly mimic legitimate business, making humans a vulnerable breach point
   In the past, many phishing emails had obvious red flags, such as unfamiliar senders, broken links or sensational content.

Today’s attackers, however, are highly skilled at disguise.

They may leverage public information to impersonate corporate clients, or forge internal notices, meeting invitations and file-sharing links. It becomes hard for employees to distinguish authenticity merely from surface details.

Once an employee clicks a malicious link, downloads a suspicious file, or enters login credentials on a fake webpage, attackers may gain access to corporate systems.

Therefore, phishing risks cannot be resolved simply by asking employees to "stay vigilant".

Enterprises must also prepare for this scenario: what happens if someone accidentally clicks the malicious content?

1. After an account or endpoint is compromised, risks may continue to penetrate the corporate intranet
   Once a phishing attack succeeds, the real danger often only begins.

Attackers may use stolen account credentials to log into corporate systems, or take control of endpoints via malware. They then keep searching for servers, shared files and other network devices.

If the corporate internal network permits broad interconnection by default, an infected PC may gain access to multiple business systems.

This is why many security incidents keep escalating in impact.

The initial trigger may just be an employee clicking an email. Yet without subsequent network boundaries and access restrictions, risks can spread laterally inside the enterprise.

1. Perimeter-only defense fails to address threats once they enter the intranet
   Many enterprises have deployed perimeter protection appliances such as firewalls and security gateways.

But cybersecurity is not only about stopping attacks from getting in.

Phishing attacks often bypass traditional perimeter entry points.

When employees actively visit malicious websites or download harmful files, such actions may appear as "legitimate connections". Once attacks enter the internal network through user behavior, the true test is whether the enterprise intranet retains sufficient security defenses.

Hence, enterprises need to move beyond single perimeter defense and build a multi-layered security system covering access, networks, business services and operation & maintenance.

II. How AINOPOL’s All-Optical Five-Tier Defense System Reduces Phishing Risks

Against phishing threats, AINOPOL holds that corporate cybersecurity should not count on blocking every single attack. Instead, multi-layered defense lines must be established.

If the first line fails to fully stop risks, subsequent network controls including identity recognition, network isolation, access control and audit management can limit attack progression.

Layer 1: Perimeter security defense to minimize incoming risks
Corporate networks first require fundamental security boundaries to defend against anomalous access and potential threats originating from the internet.

Leveraging Mengxiang gateways and other perimeter devices, AINOPOL centrally manages corporate network egresses and builds baseline network security boundaries for campuses.

Managing network exit points and access behaviors reduces direct exposure to abnormal traffic and centralizes internet gateways for easier administration.

Perimeter defense, however, is not the endpoint of the security system.

The defining trait of phishing attacks is that risks can bypass traditional perimeters through user-initiated actions.

The first defense layer aims to reduce risks, not assume threats will never penetrate.

Layer 2: Identity authentication to eliminate default trust for all network access
Phishing attacks may lead to account leaks and attempts by unauthorized endpoints to join the corporate network.

Enterprises therefore need visibility: who is using the network, and what devices are connecting.

AINOPOL unifies user and endpoint access management via identity authentication and access control. Different users and devices obtain access privileges matching actual business needs, rather than gaining broad network access automatically upon connection.

Identity authentication serves not only to verify "who the user is", but also lays the foundation for subsequent access control and security auditing.

Layer 3: All-optical micro-segmentation to restrict lateral risk spread within the intranet
If a phishing attack infects an endpoint, the most critical question for enterprises becomes:
What else can this compromised device reach?

AINOPOL all-optical networks, combined with micro-segmentation and business isolation, create clearer network boundaries for different departments, endpoints and business systems.

Network access for office terminals, servers, IoT devices and other business systems can be planned based on practical requirements to cut unnecessary direct communications between endpoints.

In this way, even if one device behaves abnormally, network boundaries can limit its reach and prevent risks from propagating across the entire corporate intranet.

Security defense is not merely about blocking incoming attacks; more importantly, it ensures threats cannot travel far after breaching the network.

Layer 4: All-optical hard slicing to protect critical business networks
Within corporate networks, business systems vary in priority.

General office networks, core servers, security monitoring systems and production workloads have distinctly different requirements for security and stability.

With all-optical hard slicing, AINOPOL independently hosts and segregates different networks according to business needs, establishing clear business boundaries on a unified all-optical infrastructure.

When security anomalies occur on office networks, the solution minimizes unintended impacts on other critical business networks.

This isolation is not simply splitting the network apart; it builds a more reasonable hosting framework aligned with real communication requirements of business services.

Dedicating distinct network spaces to critical services is a key measure to contain expanding security risks.

Layer 5: Full auditing and unified management for easier detection of abnormal behaviors
Security defense must not only "block threats", but also "see what is happening".

After a phishing attack occurs, enterprises need to quickly locate where abnormal activities took place, which endpoints are involved, and which network zones may be affected.

AINOPOL combines network management and log auditing to centrally oversee network appliances, user access and network operation status.

Log retention and network status monitoring provide a basis for subsequent anomaly investigation.

For large campuses with numerous network devices and endpoints, fully manual troubleshooting after security incidents is inefficient and prolongs response time.

The value of unified management and full auditing lies in making network activities visible, simplifying fault location, and supporting security incident analysis and response.

Phishing attacks are difficult to defend against because they exploit not just technical vulnerabilities, but people, accounts and normal business behaviors.

Enterprises cannot expect every employee to never click malicious content, nor rely on a single firewall to block all attacks.

By integrating all-optical networks with security capabilities, AINOPOL helps enterprise campuses build a more complete cybersecurity protection system spanning perimeter defense, identity authentication, micro-segmentation, hard slicing and full auditing.

FAQ

Q: What is the difference between gateway-level AV and antivirus software installed on PCs?
A: PC antivirus software scans threats after viruses arrive. Gateway-level AV intercepts threats before they enter. Malicious files are detected and blocked at the gateway before reaching employee endpoints.

Q: How do AI-generated phishing emails differ from ordinary phishing emails?
A: AI-generated phishing emails are highly customized with flawless grammar, formatting and tone, making them hard to spot visually. In December 2025, the proportion of AI-generated phishing emails surged from less than 5% to 56%, representing a 14-fold increase. Employees can barely tell the difference with the naked eye.

Q: Is a 4-million-signature virus database sufficient?
A: The 4-million-signature library covers mainstream virus strains. Paired with an intelligent detection engine, it performs real-time content inspection on files in transit. The signature library supports continuous updates to cover new viruses and variants promptly.