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tcp port 0 floodding

I found a peculiar problem in router. My log shows lots of incomming traffic from WAN(internet) to my router with TCP port 0. This is freezing my WAN link and giving DOS to my serial interface. How do we resolve the DOS attack of serial interface.

Thankx

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Accepted Solutions

Re: tcp port 0 floodding

Hi.

Regarding http://www.iana.org/assignments/port-numbers TCP port 0 is reserved.

So I think you can configure an incoming ACL on your WAN interface denying any TCP traffic with destination TCP port 0.

You should also ask your ISP to configure an outgoing ACL on his side of the line.

Regards,

Milan

1 REPLY

Re: tcp port 0 floodding

Hi.

Regarding http://www.iana.org/assignments/port-numbers TCP port 0 is reserved.

So I think you can configure an incoming ACL on your WAN interface denying any TCP traffic with destination TCP port 0.

You should also ask your ISP to configure an outgoing ACL on his side of the line.

Regards,

Milan

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