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BLOCK BROADCAST

Hi.

My problem is this:

My net (net 1) is connected with 2 wan over a 2 serial (net 2 and net 3) v35 (HDLC).

Many Pc on Net 2 and Net 3 was infected by oplaserv worm.

This worm search other pc to infect with udp broadcast.

How can i prevent udp broadcast to pass over serial lines?

I tried "ip forward-protocol udp" but nothing ....

Can you help me?

Thanks.

  • Other Network Infrastructure Subjects
1 REPLY

Re: BLOCK BROADCAST

All you need to do to block broadcast forwarding completely is to remove the helper adress from the LAN interface.

The forwarding of UDP broadcasts works as follows:

On the routers LAN interface you configure a helper-address. This is typically a unicast adress. This enables a standard, but limited range of UDP ports to be forwarded to the selected adress. You can reduce the number of forwarded protocols by configuring no ip forward-protocol udp (protocol). To forward additional protocol ports, you use the ip forward-protocol udp (protocol), without the no command.

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