Updated October 2026. First published May 2025.
A business network connects your computers, phones, printers, cameras and Wi-Fi to each other and to the internet. Getting the installation right up front saves years of slow connections, unexplained dropouts and messy closets. This guide walks through each layer, from planning to testing.
Network basics
Devices on a network exchange data in small packets over cable or radio, using protocols such as TCP/IP. Each device has an IP address, and switches and routers decide where each packet goes.
| Type | What it is | Typical use |
|---|---|---|
| LAN | Local area network inside one building or floor | Offices, schools, small businesses |
| WAN | Links several sites over long distances | Multi-location businesses |
| Wired Ethernet | Copper or fiber cable to each device | Desks, phones, printers, cameras, access points |
| Wi-Fi (WLAN) | Wireless access over radio | Laptops, phones, meeting rooms |
Example: a retail chain with 20 stores runs a LAN in each store and connects them over a WAN or SD-WAN so inventory and point-of-sale systems report to head office.
Hardware you need
- Router or firewall: connects you to the internet and controls what comes in and out.
- Switches: connect wired devices. PoE switches also power phones, cameras and access points.
- Wireless access points: provide Wi-Fi. Placement matters more than the number of units.
- Cabling, patch panels and racks: the physical layer everything depends on.
- Servers or NAS if you keep files or applications on site.
- UPS battery backup for the network closet.
Choosing cable
| Cable | Max speed | Distance | Good for |
|---|---|---|---|
| Cat5e | 1 Gbps | 100 m | Basic small-office needs |
| Cat6 | 1 Gbps (10 Gbps to ~55 m) | 100 m | Most offices |
| Cat6A | 10 Gbps | 100 m | High-power PoE, Wi-Fi 6E and Wi-Fi 7, future-proofing |
| Fiber optic | 10 – 100+ Gbps | Hundreds of meters to kilometers | Backbones between floors and buildings |
See structured cabling and fiber optic installation.
Network layout (topology)
| Topology | How it works | Pros | Cons |
|---|---|---|---|
| Star | Each device runs to a central switch | Simple, easy to troubleshoot and grow | The central switch is a single point of failure |
| Extended star (hierarchical) | Floor or IDF switches link back to a core | Standard for offices; scales well | Needs planned backbone cabling |
| Mesh | Multiple links between core devices | Redundant and resilient | More equipment and cost |
Almost every modern office uses a star or extended star. Redundant links are added between core switches where downtime is expensive.
The installation process, step by step
- Plan.Count users and devices, map outlet and access point locations, and decide on IP addressing, VLANs (for example staff, guest, phones, cameras) and internet bandwidth.
- Survey the site.Walk the space to find cable paths, the closet location, power, cooling and building rules.
- Buy equipment.Size switches for today plus growth, with PoE budget for phones, cameras and access points.
- Cable.Run cable to TIA standards, terminate on patch panels, and label both ends.
- Install and configure.Rack the equipment, set up the firewall, DHCP and DNS, VLANs and Wi-Fi.
- Test and document.Test every drop, check Wi-Fi coverage and speed, and hand over a port map and photos.
Security from day one
- Use WPA3 (or WPA2/WPA3) for Wi-Fi, and keep guests on a separate network.
- Put phones, cameras and other devices on their own VLANs.
- Change default passwords and turn on multi-factor sign-in for admin access.
- Keep firmware updated on the firewall, switches and access points.
- Lock the network closet. Physical access is network access.
Testing before handover
- Test each cable for continuity and wiring faults, or certify it if you need a manufacturer warranty.
- Check link speed on each port and PoE power on powered devices.
- Walk the space to confirm Wi-Fi signal and roaming.
- Run speed and latency tests from the internet connection to a few desks.
What does network installation cost?
| Business size | Typical setup | Typical budget |
|---|---|---|
| Small (up to about 20 people) | Business firewall, PoE switch, 2–4 access points, basic cabling | $1,500 – $5,000 |
| Mid-size (25 – 100) | Structured cabling, managed switches, VLANs, VoIP | $6,000 – $15,000 |
| Large (100+) | Fiber backbone, redundant core, multiple closets | $20,000 – $50,000+ |
Typical market ranges, not quotes. For cabling costs per drop, see how much Ethernet installation costs.
Keeping it running
- Label every cable and port, and keep the port map current.
- Monitor equipment health (SNMP or the vendor's cloud dashboard).
- Replace switches and access points before they fall out of vendor support.
- Use ping, traceroute and packet capture tools such as Wireshark when you troubleshoot. See network switch troubleshooting.
Getting help
DC Metro IT Help installs business networks across Washington DC, Maryland and Northern Virginia: cabling, racks, switches, firewalls and Wi-Fi. Every job is tested and closes with photos and a written completion report. See our services or voice and data cabling.
Frequently asked questions
What does a business network installation cost?
Typically $1,500 to $5,000 for a small office, $6,000 to $15,000 for 25 to 100 people, and $20,000 or more for larger networks with a fiber backbone.
How long does a network installation take?
Usually 2 to 10 business days of onsite work, depending on the number of drops, the building and the equipment.
What equipment does a business network need?
A router or firewall, switches (often PoE), wireless access points, cabling with patch panels and a rack, and a UPS for the network closet.
Do I need ongoing maintenance after installation?
Yes. Firmware updates, monitoring and keeping the port map current prevent most problems.
Can I combine wired and wireless networks?
Yes. Most offices use Ethernet for fixed devices and access points, and Wi-Fi for laptops and phones.