When writing a layered channel, sometime you want to decouple processing without changing the channel shape. One example would be for layered demux purposes. When layering your IInputChannel on top of a "lower" IInputChannel, you have a few options for lifetime management and pumping that are worth noting:

1. When your innerInputChannel.Receive call returns "null", that means that no more messages will arrive on that particular channel. You should Close that channel and then Accept a new one.
2. If the innerListener.AcceptChannel call returns null then your inner listener is completely done providing messages and you need to follow suit when you are through with any added messages that you may have buffered.
3. If someone calls Close/Abort on your IInputChannel, you have the option of holding onto the inner channel within your listener (and providing a new facade on top when a new channel is accepted). Alternatively, you can close the inner channel and create a new one with your new channel. That choice is entirely at your discretion (and at the mercy of your perf tuning results :))