why does using web data sources require a gateway

[db042190]

hi i'm in the middle of a course and thought things werer really making sense.  but just learned today that connecting(perhaps refreshing) from web data sources requires a gateway.  that doesnt make sense to me when the gateway seems more relevant to on prem data sources.  can thge community explain this in simple terms?

[bcdobbs · Accepted solution]

Hi,

In general a cloud data source doesn't need a gateway. 
However...

1) If your dataset or dataflow uses some on prem sources and some cloud source then they all refresh through the data gateway. This is because the mashup engine is running on that server and it minimises data movement.

2) If your cloud source sits behind a firewall that's not accessible to wider internet then one solution is to host a gateway on a virtual machine inside that firewall.