[Asterisk-Users] Sip Registrations

[jamesm]

    My question pertains to having people from random IP addresses log 
in to my Asterisk system using SIP.
I would like to be able to have a SIP phone log into my system using 
nothing but a username and password.
Based on the username the phone would be placed in a context and be 
asigned an extention.

    I was hoping something like this would work but it does not seem to:

[example1]
type=friend
authuser = example1
secret=1234
regcontext=testcorp
regexten=405
host=dynamic
disallow=all
allow=g726
nat=no
mailbox=405 at testcorp
dtmfmode=rfc2833
canreinvite=no
   
    any ideas?