IP Security have a range of application specific security mechanisms eg. S/mime, Pgp, Kerberos, Ssl/hTtps however there are security concerns that cut across protocol layers would like security implemented by the network for all applications Q: If security mechanisms in app layer have implemented. Security is needed in network level? Or vice versa? 復大软件学院4 IP Security • have a range of application specific security mechanisms – eg. S/MIME, PGP, Kerberos, SSL/HTTPS • however there are security concerns that cut across protocol layers • would like security implemented by the network for all applications • Q: If security mechanisms in app layer have implemented. Security is needed in network level? Or vice versa?