Centrend, Inc.

Is My Internet Service Provider’s Firewall Strong Enough?

When an Internet Service Provider (ISP) installs internet access in your business, you are usually provided with a router/firewall combination. Do you need to invest in a commercial-grade firewall, or is the ISP’s firewall sufficient?

Let’s start with a simple description of what a firewall is and how it protects your network from intruders.

The role of a firewall is to determine what data can come in, and what data will not be allowed. The pieces of data that arrive at your firewall are called packets. For a basic firewall, the rule is simple:  If somebody requested the packet, it is allowed into the network. If the packet was not requested, the firewall burns the packet. The graphic below shows a typical small business network.


When a packet approaches the firewall, It is analyzed to see if it should be let in. A basic firewall is only going to ask one question before deciding to let the packet of information into the network: Was the packet requested by someone inside the firewall?


When a packet approaches a commercial-grade firewall, it is scrutinized much more carefully and in BOTH directions – IN and OUT, When it decides to let the packet pass through, the decision is logged in a database. The activity log proves invaluable in chasing down and isolating data breaches. Here are some of the things a business-class firewall considers before letting a packet pass:

  1. Was the password Requested?
  2. Is the packet SAFE to let in or does the packet contain a virus, malware, or other malicious code?
  3. Is the destination internet address listed on any “blacklists” due to bad activity coming from there?
  4. Is traffic from the country of origin allowed?
  5. Does the corporate policy for content filtering allow access to the material that is on the destination website?

The chart below shows examples of the types of traffic that are allowed or blocked by the different firewall options.

Effectiveness of Commerical Grade Firewalls

The commercial-grade firewall is not only a strong defense against unsolicited traffic, but it also gives business control over what content is allowed on their network. Business-class firewalls are surprisingly affordable. If you would like help evaluating whether it’s right for your home or business, please give us or fill out the contact form below.

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