DeF-Sec

(985)-635-9110

IT & Cybersecurity Solutions for Louisiana Businesses

One local expert for your network, your security, and your IT. We protect what you have, build what you need, and bring in trusted partners for the rest, so you never have to figure it out alone.

Our Services

What We Do

Cybersecurity and IT solutions for small businesses and homeowners across the Northshore and Greater New Orleans.

Rows of server racks connected by organized bundles of blue and yellow ethernet cables running through overhead cable trays in a data center.

Networks & Wi-Fi

Clean, documented installs and Wi-Fi built for coverage, speed, and security from day one.

Cybersecurity

It all starts at the network. We find the gaps and close them, and bring in specialists for penetration testing, threat detection and response, and security leadership when you need more.

IT Solutions & Support

Fast troubleshooting when something breaks, plus the right internet, cloud backup, and business phone providers when you need them, with one point of contact.

Learn More

Our Methodology

See how we design, implement, and secure your IT infrastructure with proven, industry-standard practices.

1. Scope & Documentation

We start every project by scoping exactly what you need, then map and document your entire network in a detailed plan for you to review before we deploy any changes.

2. VLAN Segmentation

We isolate critical devices and segment your network into VLANs to contain potential threats and protect sensitive data.

VLAN Segmentation Diagram

Swipe the diagram sideways · tap a VLAN to focus it

Network segmentation — flat vs. VLANs The same six device types on one network, and on a segmented one. FLAT NETWORK — ONE BROADCAST DOMAIN Internet Router + AP Front desk PC Guest laptop COMPROMISED File server Card terminal Smart TV Guest phone One infected laptop reaches all of it. SEGMENTED — SIX VLANS BEHIND ONE FIREWALL Internet Firewall Core switch Traffic between VLANs is routed by the firewall, so every crossing hits a rule. Traffic inside a VLAN never leaves the switch. VLAN 10 MANAGEMENT Firewall admin Switches Access points VLAN 20 SERVERS File server Domain controller Backups VLAN 30 STAFF Workstations Laptops Company phones VLAN 40 POS Card terminals Register PCs VLAN 50 IoT Printers Thermostats Smart TVs VLAN 60 GUEST Guest Wi-Fi Contractors WHAT IS ALLOWED TO CROSS Guest Internet only. Never sees a company device. IoT Firmware and time out. Nothing in. POS The payment processor. That is the whole list. Staff The file server, on named ports only. Management Reachable only from Management, over VPN. Illustrative reference design · every network gets its own plan DeF-Sec · def-sec.com

3. Firewall Configuration

We design and implement firewall rules based on the principle of least privilege, securing your perimeter against unauthorized access.

Firewall Methodology

Firewall methodology — how a rule earns its place

The order the work happens in, and what the finished ruleset looks like.

1

Inventory first

Every device on the network, and what it legitimately needs to reach. You cannot write rules for traffic you have not identified.

2

Start at default deny

The baseline is that nothing is allowed. Rules are exceptions you argue for, not defaults you inherit from the box.

3

Open the service, not the network

Staff get the file server. Not everything else that happens to sit beside it. The less a device can reach, the less it can damage if it gets infected.

4

Document the reason

Every rule carries why it exists. A rule nobody can justify is a rule that gets removed at the next review, not grandfathered in.

WHAT THAT PRODUCESa ruleset you can hand to the next person and have them understand it
SOURCEDESTINATIONSERVICEACTIONWHY
StaffServersSMB (v3), HTTPSALLOWStaff need their shared files. Being on the network is not enough — your group decides which folders open.
StaffManagement—DENYNobody should be able to change the firewall from a regular laptop.
POSPayment processorHTTPSALLOWA register only needs to reach the card company.
POSAny other VLAN—DENYA register has no reason to touch anything else.
IoTInternetHTTPS, NTPALLOWSmart devices get updates and the clock. Nothing else.
IoTServers, Staff, POS—DENYA smart TV should never reach your files or your registers.
GuestInternetWeb onlyALLOWVisitors get Wi-Fi, not your network.
AnyAnyAnyDENYEverything not listed above is blocked. That is the default, not the exception.

Everything not listed above is blocked by default — the last rule is what is really doing the work. And getting on the network is not the same as getting access: a staff laptop can reach the file server, but which folders open is decided by who the person is.

Illustrative reference design · every network gets its own planDeF-Sec · def-sec.com

4. WiFi Optimization

We analyze and optimize wireless coverage using precise heatmap analysis to ensure seamless connectivity throughout your facility.

Wi-Fi Coverage Slider

One router vs. three placed access points

Same building, same walls. Drag the handle to see what changes.

One consumer routerSignal falls off hard past the first interior wall. Two rooms sit below usable.
Three access pointsEach one centred in the space it serves and clear of walls. Nothing occupied drops below −60 dBm.
−30   −40   −50   −57   −65   −72   −80   −90 Voice and video need −65 dBm or better
Predictive 5 GHz model · illustrative example, not client dataDeF-Sec · def-sec.com

Your Local Cybersecurity and IT Partner

Founded by a Louisiana Army National Guard IT Specialist, DeF-Sec brings military discipline to protecting small businesses and homeowners across the Northshore and Greater New Orleans. Tell us what worries you about your network, and we’ll take it from there.