The Newest Version of the Database Mirroring Whitepaper for SharePoint has been released

Using Database Mirroring with Office SharePoint Server and Windows SharePoint Services

 Wow! This one took a while to update. We added more prescriptive information on the type of supported topologies. It also recommends SQL connection aliasing for failover within a farm. We are still debating high performance mirroring (async) internally so you won't see any info on that. Also, the mirroring setup instructions talk only about certificate authentication. We use windows authentication internally and I think most people would be interested in windows auth as well. Here's how to setup mirroring with windows auth with a specific IP in SQL.

CREATE ENDPOINT Endpoint_Mirroring
STATE=STARTED
AS TCP(LISTENER_PORT=14999
 , LISTENER_IP = (10.0.0.X))
FOR DATABASE_MIRRORING (AUTHENTICATION = WINDOWS[Negotiate], ENCRYPTION = DISABLED,
ROLE=ALL); 

Run this command on both the principal and mirror. When configuring the witness (if applicable) replace ROLE=ALL with ROLE=WITNESS. The command will create the endpoint for mirroring listening on port 14999 (an arbitrary unused port) using IP 10.0.0.x (replace with your own IP). The endpoint will negotiate NTLM or Kerberos. Finally, encryption is disabled. Replace DISABLED with SUPPORTED if you need to mirror over a public network. See https://msdn2.microsoft.com/en-us/library/ms181591.aspx for a complete description of the create endpoint syntax.

I highly recommend having a back channel NIC for your mirroring traffic. Mirroring will definitely saturate a link and you don't want frontend and backend traffic sharing a single GB connection. Configure the above command to use that IP. See my previous post about mirroring and bandwidth.