. Another solution is to perform a password recovery on the router. You can manage access control and policy, create separate collision domains, and implement port security at this layer. from venturebeat.com I have 1 layer 3 switch 3550 and i created on this switch 02 vlans , vlan 192 and vlan 137 and assigned both. You can manage access control and policy, create separate collision domains, and implement port security at this layer. All products are designed and built with security in mind.