Using CAS without modify existing applications?

[hezjing]

Hi!

After a very brief look at CAS, am I correct to say we cannot avoid to
customize the existing applications to run Single Sign On using CAS?

For example, there are currently few legacy web applications running
in my environment, each application has their own login page and
method. I have to modify all the login module of all these
applications to have the Single Sign On feature, correct?


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Hez