How can a external caller join a conference?

Hi all,

I am new to asterisk. I can understand how a local user can join a conference by dialing extension, say 600 for the conference room. But if you have dialed in from the outside on one of the available zaptel lines how can one join a confernece? Just typing in the extension while talking to someone?

Basically the situation we have is when a client phones and start disucssing something a staff member and then I need to join in temporarily. How can I do this?

thanks

Direct dial would allow a caller form outside to dial in the conf.
(need to use password)

two ways i can thnk of-

  1. transfer the caller to a conference room, then both you and staff member dial into the same conference

or

  1. use a phone with conferencing features built in. both eyebeam and the polycom 501 phones have built-in conferencing features, and that would be my vote, especially if this is going to be only three users total.

there is probably another way to do it, but those are the two ‘easy’ versions.