Acer Veriton N2620G - Manual (Page 45)

Connections | 45
The Firewall Settings Section

Use alternative address for firewall connection-Mark this
checkbox if you need the ICA session to connect to the Citrix
server's external IP address. The external address for the server is
specified as the alternate address.

Proxy Settings-If your Citrix environment utilizes a proxy server,
then choose the appropriate type from the Proxy Type field. Enter
the address of the proxy server and port number in the Proxy
Address and Proxy Port fields, respectively.
The User Log On Section

User Name-Specify the name of a user account to log on as. This
is an optional field.

Domain-Specify the domain to log on to. This is an optional field.