Question : Need to get to intranet on different addresses in and out of LAN

Hi Experts. I'm running a site with over 100 users on laptops. The shortcut for their intranet is addedd through the domain log in and is a shortcut to https://intranet.company.com.  
This is fine when they access the intrant from outside the lan, but very slow when they are on the LAN as they are going out via our internet connection and then back in via another ADSL.
They need to be able to access normally from outside but directly when on the LAN.  SHould I be adding something in the local DNS perhaps?  I'm using DHCP with a local DNS server on the LAN.   Thanks

Answer : Need to get to intranet on different addresses in and out of LAN

If the website is hosted on ur local lan create a cname in dns. Ask the user to browse using cname & internall if the website is hosted in local lan it should be access in intranet not through internet.
You need to open port to browse the site for local lan most probably port 80.
For Https, you need enable SSL & create a certificate.