Hello Vijay,Just go through this short cisco doc regarding generating CSR for Third-Party Certificates and Download Unchained Certificates to the WLC:http://www.cisco.com/en/US/tech/tk722/tk809/technologies_configuration_example09186a00806e367a.shtml
Hello,Like Viren said mac-address filtering is not the most secure way as they can be easily spoofed.Why don't you try Peer-to-peer blocking.Peer-to-peer blocking is applied to individual WLANs, and each client inherits the peer-to-peer blocking set...
Hello,It could be that DHCP failed because the encryption between the access point and phone do not match.For more clarity please refer to the troubleshooting guide for 7921:http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7921g/6_0/english/admin...
