Among small businesses, especially — security is crucial to your business model. Trust us. In those early days, one data breach could put your out of business for good: not only will you lose money, but customer trust, and the inevitable costs associated with workflow disruption and lost time. That being said, adequate security is a must.

You may have heard the buzzword thrown around — but there’s really not much to it.

Network perimeter security is the very first layer of defense that your network has against external threats. It’s a security fence that delineates your network perimeter, or the boundary between your internal, privately managed and owned network and its public, externally managed counterpart.

Like any fence, it also has a gate. The place where two networks meet, acts as the entry point between all forms of communication, both inbound and outbound. Unlike your standard gated-fence system, however, your network perimeter isn’t simply a singular layer.

A sound network perimeter security system involves multiple layers of defense working in tandem with one another. For instance, every computer has a firewall built into its hardware which filters web traffic, like a sieve, allowing only the good, secure Internet communications to take place between your company and the Internet.

Of course, overtime our firewall technology has evolved to include more advanced threat detection features such as anti-virus mechanisms. These software versions of firewalls can also detect malicious intrusions, inspect SSL security, ward off spam, and allow for virtual networking (secure access, off-site).

At its core, however, the firewall’s main function is to control access to your network from outside sources. And no, that function, has yet to be rendered obsolete by superior technology – which is a popular rumor.

Still interested in security systems? Your IPS is another network perimeter defense mechanisms that effectively catches attackers which have managed to slip past the firewall and router layers. In fact, IPS stands for “Intrusion Prevention System.” Essentially it’s the security line at the airport. With a firewall, you can check your bag with a proper ID and buy a ticket; it’ll let that through. But the security line is really where your identification and belongings are scrutinized. That’s the IPS, double-checking the work of the firewall.

You can also install a VPN or “Virtual Private Network,” on your system, which allows users to securely access a private network and share data remotely through public networks via encrypted communications. Given how most of us check our work email from our smartphones — VPN’s are a crucial component to any sound security system.

Again, all of these network perimeter security features work in tandem with one another to vet the legitimacy of your network communications. They’re control devices. They control traffic like customs officers, or airport security guards.

However, here’s the catch. The growth of virtualization has taken data out of the traditional scope of hardware-bound firewalls, designed to protect your physical servers. When it comes to cloud-based technology, the security of that data and your access to it, lies with a service provider on the outside of your internal network. Thanks to this technological development, our network perimeters have dissipated; decentralized, they’re beyond our control — to a point.

These days we have to trust and rely on the security measures taken by our service providers. For instance, cloud providers naturally deploy the best practices for network perimeter security and intrusion detection, yet, its interfaces are public and therefore, the data contained within the cloud system necessarily reside inside two perimeters. That’s a twofold increase in the surface area of that data’s perimeter, making it technically more open to attack. Make sense?

Furthermore, the consequence of BYOD, or “bring your own device” policies is that your network perimeter needs to open up pathways to certain services such as an intranet so that smart devices can stay connected to your corporate network. Even with a VPN, an uncontrolled device could very easily be infected with malware and act, unwittingly as a compromised conduit to its corporate network.

In short, defending your network perimeter in the face of unmanaged devices and trusting the security measures of cloud-based services is a challenge. Plus, the effectiveness of each layer of your security systems may be impeded if you fail to make updates or if a connected device is misconfigured.

Unfortunately, you may have every defense system in place, but a misconfigured system is a sitting duck for cybercriminals. That’s where your IT support comes into play, ensuring that your network systems are always up-to-date and properly configured.

Remember, no single defense system can get the whole job done, especially given the scope of your network and the amount of cyber threats out there; but we live in an age where there are plenty of solutions available to your company to keep that fence strong and sturdy.

Just know that your network perimeters are constantly changing but security is a challenge that you’re equipped to manage.

Today, your network perimeter security system should be designed flexibly to account for future threats. And while you can implement firewalls, routers, VPNs, and IPSs internally, you’ll want to supplement those efforts with added security mechanisms, especially when deploying cloud solutions and working with connected, smart devices.