“We only have a few dozen people. Do we really need a firewall? Isn’t a router enough?” This is a common question from SME owners. The answer: as long as your company has internal systems, external-facing services, and cares about data security, a firewall is not optional. But don’t let big-vendor salespeople talk you into a heavy-duty appliance you will never use. Today, based on company size and real needs, let’s lay out clearly what a firewall actually does, how SMEs should choose one, and how to deploy it.
First, the conclusion: a router is not a firewall
A home or consumer router only handles “can we get online,” while a firewall handles “who can get in, who can get out, what is allowed, and what is blocked.” The limited protection built into a router is essentially useless against port scans, intrusions, ransomware, and employees wandering onto whatever sites they like. Companies with internal business systems, financial data, or externally accessible services should deploy a professional firewall.
What a firewall actually blocks for you
- Blocks attacks from outside: automated programs scan your IP and probe your ports on the public internet every day. A firewall hides services that should not be exposed and allows only necessary access, greatly reducing the risk of intrusion and ransomware.
- Controls access from inside: which devices can reach the internet, which internal systems they can access, and separating guest networks from office networks are all governed by firewall policies.
- Filters threat traffic: a good firewall can identify and block viruses, trojans, malicious websites, and phishing links, stopping threats at the traffic level before they get in.
- Internet usage management: how bandwidth is allocated during working hours, whether video streaming is permitted, and who is consuming the network can all be managed by policy, saving bandwidth while supporting compliance.
- Keeps audit logs: who accessed what and when is recorded and traceable if a security incident occurs. This is also a requirement of MLPS 2.0 (China’s Multi-Level Protection Scheme) compliance.
How SMEs should choose a firewall
| Company size | Typical needs | Recommended direction |
|---|---|---|
| Fewer than 10 people | Basic protection, guest isolation | Enterprise-grade router with security features / entry-level firewall |
| A few dozen people | Threat protection, internet usage management, logging | SME-class next-generation firewall (UTM/NGFW) |
| Hundreds of users / multiple branches | High performance, multiple WAN links, centralized management | Mid-to-high-end firewall + unified policy management |
When selecting, focus on these points:
- Is the throughput sufficient? Firewall performance drops once security features are enabled, so leave headroom. Don’t buy something with impressive specs that bogs down the moment you turn features on.
- Do the features match your needs? SMEs need practical functions such as threat protection, internet usage management, VPN, and logging. There is no need to pay for a pile of advanced features you will never use.
- Is it easy to manage? If you have no dedicated security staff, choose one with a visual console and straightforward policy configuration. Something so complex that it needs a full-time person watching it daily becomes a burden instead.
- Does anyone help you configure it? Buying a firewall is only the first step. Misconfigured policies are as good as having no firewall at all, and can even block legitimate business traffic. Having reliable people to plan and maintain it matters more than the appliance itself.
The most common pitfall: installed does not mean secure
On site visits we often see two extremes: one is no firewall at all, with business systems and finance computers sitting wide open next to the public internet; the other is a good firewall bought but left entirely on default settings, with ports that should be closed still open and networks that should be isolated still connected, turning a device worth tens of thousands of yuan into a router. A firewall’s value is 70% in policy configuration and 30% in the hardware itself. Buying the right one is not enough; it has to be configured properly and maintained continuously to actually do its job.
Frequently Asked Questions
Q: We already have antivirus software. Do we still need a firewall?
A: Yes. Antivirus runs on the computer and detects threats after the fact; a firewall intercepts at the network entry point before the fact. They operate at different layers and work best together.
Q: Will a firewall slow down our network?
A: Not if the model matches your needs and is configured properly. Slowness only happens when the model is undersized and the features enabled exceed its processing capacity, which is why you should leave performance headroom when choosing.
Q: Once we have a firewall, are we absolutely secure?
A: There is no absolute security. A firewall is an important line of defense, but it must be combined with internal network segmentation, data backups, employee security awareness, and timely patching to form complete protection. One device alone is not enough.
Q: We have no dedicated IT staff. Who will configure and maintain it?
A: You can hand it to a professional network security operations provider, which manages everything from model selection, deployment, and policy configuration to routine maintenance and log inspection, paid as needed. That is more cost-effective than employing a full-time security engineer.
Want a firewall but worried about buying the wrong one, not knowing how to configure it, or having no one to manage it?
Siwenlide provides firewall selection, deployment, and operations for SMEs in Beijing and surrounding areas: we choose the right model for your size and business, configure policies, threat protection, internet usage management, and log auditing properly, and keep maintaining and inspecting them, so your firewall genuinely blocks risk instead of sitting there as decoration. We ourselves have long-term operations responsibility for the firewall equipment of multiple enterprises. Visit siwenlide.com or call 400-686-2011 to talk about your current network security situation.
