best practives multi-homed BGP 2 physical locations

[source_route at yahoo.com (Philip Lavine)]

Easy part:
I need to provide my users acces to the internet from my HQ site via a local Internet connection or via a?colo.? 
?
Hard part:
I also need to provide incoming access to hosted apps (HTTP, FTP, SMTP) from either location, so if the colo internet connection goes down the traffic can re-route to the HQ server farm and visa versa.
I am in the process of purchasing an AS and ip space. Is it advisable to use the same IP space at both locations and run iBGP over a dedicated L2 connection between the sites.
?
P
? 

________________________________
 From: Mick O'Rourke <mkorourke at gmail.com>
To: Philip Lavine <source_route at yahoo.com> 
Cc: "nanog at nanog.org" <nanog at nanog.org> 
Sent: Thursday, June 14, 2012 2:48 PM
Subject: Re: best practives multi-homed BGP 2 physical locations
  

As in 
- use of multi or single AS?
- private, vpn or other dci?
- etc 
What's the purpose of the site? Or what end result are you trying to achieve?
 
On Jun 15, 2012 6:04 AM, "Philip Lavine" <source_route at yahoo.com> wrote:

?Is there any best practices documentation on how to run BGP multihoming accross two phyiscally seperated sites.
>