We have HP Procurve 5400 series switches at an organization with about 500 IP devices spread across about 15 VLANs. We also have HP Procurve 2848 switches for the server racks. We have an issue where occasionally the network will perform very badly and we will find a device that seems to assume all IP addresses and MAC addresses. This fills the primary VLAN of the guest machine's DHCP pool with bad addresses and any server on that VLAN with an IP conflict. While the guest machine changes it is usually caused by a developer using a desktop switch or bridging with wireless on an entry-level wireless AP. We have recommended using better access points but the desktop switches are unavoidable. Is there anything on the HP switch that we can set that would prevent a single machine or desktop switch from taking down the network? I.E. maybe limiting the number of mac's or something?