Port Security Overview

When comes to online security there may not be anything more important than creating a “locked down” network that outsiders and attackers cannot breach just by detecting the network in the first place.

Unfortunately, even though we depend on the internet and connected networks today more than any time in human history far too many people are ignorant of proper internet security – like port security – and are leaving themselves open and exposed without even realizing just how dangerous a situation they are in the first place.

For example, you’d be surprised at the sheer volume of IT professionals that do not understand the extent of how vulnerable Ethernet LANs are when it comes to attack simply because the switch ports are left on as a default setting across the board.

We’ve gotten very complacent when it comes to network security and expecting the hardware and software solutions we take advantage of to be set up properly right out of the box, and that’s a major problem in and of itself.

Preassembled or preset security settings are going to be open to an extreme amount of vulnerabilities if they are left unchecked if only because cyber criminals and outside attackers are going to have ample opportunity to analyze those systems and their vulnerabilities – creating bridging solutions that work on any network that hasn’t changed these settings.

DOS attacks that occurred at Layer Two can leverage address spoofing to breach otherwise secure networks, and even if an administrator has complete and total control over the network that doesn’t mean that it is safe and secure in the future, either.

Port security is a big piece of the puzzle when it comes to locking down major vulnerabilities like switch ports, for example – and that’s where you’re going to want to focus at least some of your initial security audits when you are getting a new network up and running or analyzing an existing setup for vulnerabilities.

Analysis is the First Step

The fact that most modern cyber criminals are going to take advantage of some kind of port scanner or open port checker to spots vulnerabilities and conduct reconnaissance on your network is something that most port security specialists understand, but a lot of them aren’t using the same kinds of tools to analyze their own networks and spot vulnerabilities before they are under attack.

This has to be – HAS to be – one of the very first things you do when you are conducting an initial analysis and audit of your network.

Port security begins with using the same kinds of solutions that your potential attackers are going to use to spot flaws in vulnerabilities, getting a look at your network through the same tools and the same lenses that they are going to be using.

Not only will you gain a lot more familiarity with the kinds of port scanner and port checker tools cyber criminals are using to exploit your network, learning how they think and how they work, but you’re also going to spot the kinds of flaws that you might not have seen from your side of the fence (so to speak).

It’s important to remember that open port scanner and online port scanner solutions aren’t necessarily malicious in and of themselves. Sure, they can be used to “see behind enemy lines” by cyber criminals looking to find in exploit vulnerabilities. But they can also be used by port security experts to analyze their own setup, find their own flaws, and patch those holes in vulnerabilities before it is too late.

Focus on Switch Ports

Unless you are going with a 100% air gapped network (that’s not really practical for 99.99% of organizations out there) you’re going to need to employ switch ports and that means you have to focus on these areas first for your port security to be effective.

The first thing you want to do is minimize the number of MAC addresses that can connect to a single switch port. This allows you to limit damage significantly should a port be exposed as vulnerable or should a port be hijacked, as it will instantly trigger security actions as soon as more than the limit of addresses to a single port have been hit.

Secondly, you will want to automate a process with the help of your port scanner that allows your network to automatically discard ANY traffic that can be traced back to those compromised ports or systems. On top of that, a user generated log message should be recorded so that the breach can be further analyzed later down the line and that human port security experts are alerted to the breach in real time as well.

There are a couple of different violation modes that you can set for port security, ranging from Protect and Restrict or Shut Down options all the way up to Sticky options (which itself isn’t really a violation mode). You will want to learn how to leverage these different modes to create a bubble of port security and safety for your network, finding the right specific violation modes for individual switch ports so that you can allow for easy communication across your network without creating any potential security flaws that can be exploited later down the line.

As always, it’s a good idea to use port scanner/port checker and online port scanner tools a regular basis to analyze your network.

Cyber criminals are always on the lookout for the “next big thing” that allows them to breach a system and you want to be sure that you are staying as far out ahead of them as possible.

Make these kinds of analysis and audit procedures a regular part of your port security, along with the information we shared above, and you should have little problem locking down your network and securing the data that you contain within it more effectively.

There’s obviously a lot more that goes on behind the scenes and under the hood when it comes to port security than what we’ve touched on in this quick guide but if you focus on the details above you’ll be in a great starting place with a solid foundation.