connection XI to the Internet

Dear Guru's

We have to connect our XI server to the Internet and we are thinking about the following 2 solutions:

1./ Proxy server with a local adapter engine both in the DMZ which will be connected the Central instance of the XI server behind the DMZ.

2./ Not using a local apter engine but using only a proxy, which is placed in the DMZ (and connect this proxy to the XI server behind the DMZ)

questions:

1./ Which solution should we use ?

2./ Are there other solutions available ?

3./ Can a proxy handle all protocols ?

cheers

Richard