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Checking router for security issue

Is there any way to check cisco 871 router.As my router is directly connected to DSL modem and i want to know who is using my router to access Internet

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Re: Checking router for security issue


I am not entirely clear what you realy need. It sounds like you want to see what traffic is passing through the router to the Internet. If that is the case there are several things that you could do:

- you could put an access list on the router interface with a statement permit ip any any log. This will permit traffic to pass and will create log records with source address and destination address. You could look at the log records on the router or could send them to a syslog server.

- you could turn on ip accounting and look at the accounting records to see what the traffic is.

- you could turn on flow switching on the router interface and look at the netflow records to find source and destination addresses, port numbers, etc. If you look at the netflow records on the router you will get a snapshot of traffic at that particular time. If you export the flow records to a netflow collector then you can analyze traffic over longer periods of time.

So there are several alternatives. Which one would be best for you depends on exactly what you are trying to achieve.