Node.js client connection and Azure Transaction billing cost

Question

I am quite new to Node.js usage inside Azure platform. What I understand is , Node.js technology is like broadcast event model from "Server---->to-->Client" data push. Technically, node.js client is connected to node.js(Server) via long polling permanent connection. It means, node.js(Server) keep sending some heart beats to client to maintain the connection alive.

In such cases, if we deploy node.js server in Azure webrole/workerrole, if 100 browsers are connected to node.js server HTTP url, there will be always http heartbeats flowing from Azure server to client browsers. If my assumption is correct, does azure take this heartbeats as transactions into total billing. Can anyone help to get some inputs on how node.js impact the billing for 1000s of browsers/http clients connected to a node.js running inside azure.

I tried running fiddler web traffic tool in node.js/Client PC and observed that, every one minute one HTTP is invoked. Does this mean, HTTP handshake happening every minitue between client PC and node.js/server machine while node.js server is idle. If yes, how node.js help reduce the traffic between client and server ( like Periodic Polling Vs Long Polling).

Two different questions :

1) billing cost of using node.js inside azure ?

2) why I see http reply signal in node.js client PC while server is idle ?

Thanks Veda

Answer 1

I'm not sure about the second part of your question, but as far as billing goes, transactions only apply to Azure storage, CDN and access control. In your case all you are charged for is for the data volume of the responses from your servers (data that comes into the data centre you're not charged for). The most this will cost you is $0.19 per GB if you're hosting out of Asia Pacific. It's only $0.12 per GB if you're hosting out of the US. You will be spending much, much more money on compute instances.