Is Edge Node different from Reverse Proxy?

[#1]

I am designing a distribution architecture for production environment. But due to little budget, I must cut some of machines, which are not required for production environment. So, I have a question on Edge Node.

Is there any difference between Edge Node and Reverse Proxy?

As I see the document of distribution architecture, Edge Node is a gateway to communicate between the cluster and outside its network. And, the idea behind Edge server is similar as Reverse Proxy. So, I was wondering why do we need Edge Node instead of Reverse Proxy.

[#2]

@Kosuke Kikuchi

Hadoop "Edge Nodes" are light weight nodes which has the Client Binaries basically the are not designed to store the data. The Clients running inside the Edge Nodes (like HDFS client) are actually responsible for performing the operations like copy/put of files to HDFS (metadata will be stored on NameNode and the DataNodes will actually store the data/content of the file.
To know more about the Edge Nodes please refer to:
https://community.hortonworks.com/questions/106800/role-of-edge-node-worker-node-in-file-copying.htm...
http://www.dummies.com/programming/big-data/hadoop/edge-nodes-in-hadoop-clusters/


However the concept of "Reverse Proxy" is very different. In general a reverse proxy is a type of proxy server that retrieves resources on behalf of a client from one or more servers. These resources are then returned to the client as if they originated from the Web server itself.
https://en.wikipedia.org/wiki/Reverse_proxy

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