How do I curb over-zealous barking?

We have two daschund adult dogs who get a little over-zealous with their barking.
I'm fine with them letting us know people have arrived at our house, but then they'll continue to bark after we have obviously welcomed the new people, and they'll often start up again as they leave the house.
We do have small puppies at the moment, which is making this whole situation worse as the parent protect them, but it was an issue prior to their arrival. It's getting a little frustrating!

 

The only thing i can suggest for this is when people arrive and they start barking, put them in a different room.
Once they stop you can let them out, If they start again but them in another room again.
Keep trying this and hopefully you should get a result where they do not do it.

Sorry i could not be of more help.

Mike