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Explain SPI (Stateful packet inspection) firewall)


Explain SPI (Stateful packet inspection) firewall)

Can someone explain how SPI (Stateful packet inspection) firewall works and what are the benfits?

Do you need to run a software firewall if you have a router with SPI (DG834G)?

Community Veteran
Posts: 14,469
Registered: 30-07-2007

Explain SPI (Stateful packet inspection) firewall)

The following will hopefully answer your first Q (Hint... all found with a google search)

For your 2nd Q, it's entirely up to you. I still run ZonaAlarn even though my router has a hardware firewall. Like most things I prefer to double/triple protect my system to reduce the likelyhood of one failing for some reason.

Also a SPI firewall is only as good as the person who configured it. If the configuration is flawed, having a 2nd layer (software firewall) is a bonus.

The only drawback may be conflicts between the two firewalls and having to configure 2 sets of firewall rules etc to allow games and other apps through but I have ot found that to be a problem I could not resolve yet.

Explain SPI (Stateful packet inspection) firewall)

Thanks for your replies.

I wasn't being lazy, just looking a layman explanation.

After reading your links I think having a software firewall also is a good idea.
It would let me have some control over individual programs etc.


Explain SPI (Stateful packet inspection) firewall)

As you say, a software firewall will give you control of outgoing connection attempts, such as may happen with a virus.
An SPI firewall will not stop packets getting back to the PC if the connection has been instigated by a virus or malware programme on your PC. A Software firewall will alert you to this.