Listening Channel vs. Host TP Channel in Oracle B2B 11g

In 10g era of Oracle B2B, we had two kinds of channels to send/receive documents –


1. Internal Delivery Channel – IDC’s (Internal Delivery Channels) are used to enable Oracle B2B to communicate with backend applications. When I say backend, then it may be any application/product running behind Oracle B2B within same enterprise network. 

In case of an outbound flow, Oracle B2B receives documents from backend applications through an IDC and sends it to the targeted remote trading partner after required processing. 

In case of an inbound flow, Oracle B2B receives documents from remote trading partners through a Delivery Channel and sends it to backend application through an IDC. 

In Oracle B2B 10g, there were only two default IDC’s - IP_IN_QUEUE and IP_OUT_QUEUE(both are AQ’s) where as in Oracle B2B 11g, we have two more default IDC’s which are B2B_IN_Queue and B2B_Out_Queue (both are JMS) however at a time either of JMS or AQ IDC’s may be active.

2. Delivery Channel – DC’s (Delivery Channels) are used to enable Oracle B2B to communicate with remote trading partners. 

In case of an outbound flow, Oracle B2B sends the document to remote trading partner using the remote TP’s DC selected in the agreement, however in case of an inbound flow, Oracle B2B receives a document through a Host TP delivery channel. 

In Oracle B2B 10g, there is one default Host TP delivery channel – http://host:port/b2b/transportServlet and similarly in Oracle B2B 11g, we have one default Host TP delivery channel – http://host:soa_server_port/b2b/httpReceiver 



Now after brief introduction of IDC and DC let’s come back to our topic – Listening Channel vs. Host TP channel. 



Host TP Channels – Channels defined under host TP configuration can be either used as an IDC (if “internal” checkbox is checked) or it can be used as a shared delivery channel for all remote TP’s (if “internal” checkbox is NOT checked).



The first use is something which you are very familiar with, but second one is a new feature. If you mark a channel, defined under host TP configuration, as external then it serves as a common delivery channel that all remote trading partners can use as their delivery endpoints and will appear in the list of channels under the remote trading partner in the agreement(as this is considered outbound delivery channel).



Listening Channels – A listening channel listens on an endpoint for messages from remote trading partner or backend applications hence it can be used as an IDC or as a DC, depending upon the “internal” checkbox selection but in both the cases it is used to send messages to your Oracle B2B system. When a Listening Channel is marked as External (Internal checkbox not selected in the channel attributes), then it can be used by Remote Trading Partner(s) to send messages to your B2B system (Inbound). 



When a Listening Channel is marked as Internal, then it can be used by backend application(s) to send messages to your B2B system (Outbound). 



A listening channel never participates in any agreement hence it can be modified or deleted without affecting any existing deployments.



There is one more thing very important here that the channel’s marked as internal can be of “Generic Protocols” only. No internal channel can use any other protocol except “Generic” ones however Oracle B2B allows to select any protocol for an internal channel.

http://anuj-dwivedi.blogspot.sg/2010/10/listening-channel-vs-host-tp-channel-in.html