SPAN enables you to capture traffic on one or more ports, including VLANs, and to redirect the captured traffic to a port with a protocol analyzer or probe connected to it. RSPAN has the destination port located on a different switch. You can capture traffic from Layer 2 and Layer 3 interfaces, including EtherChannels. Use the monitor session command to set up SPAN. The NAM is an RMON probe that fits into the chassis of a Catalyst 6500 switch. It has no physical ports, but two logical ports. It requires an RMON management station to process the captured traffic.
You should assign passwords to your switch with the password and enable secret commands as well as restricting telnets with the access-list and access-class commands.
You can ...