Communication between Logstash and Redis is encrypted or not?

I have many log sources with a huge number of log data, so I'd like to add Redis as message broker to avoid back-pressure and data loss. My architecture is:

Filebeat -> Logstash -> Redis -> Logstash Indexer -> Elasticsearch

I know it supports encrypted communication between Filebeat and Logstash, but I don't know if it's secure and encrypted between Logstash and Redis. Someone said Redis doesn't support encryption. If that's true, how do people use it in an enterprise log solution? Is there any ways to secure the communication between Redis and Logstash?

I'm quite new to ELK stack, hope getting your help on it. Thanks a lot!

http://redis.io/topics/encryption

You could secure the connection between logstash <=> redis using stunnel. But I would rather suggestion, using filebeat output to redis directly. And setup redis mentioned here, https://medium.com/@jacoelho/secure-redis-dff568ef0ea0#.z1rise9ya.

So you data generating nodes will be configured with filebeat writing to stunnel locally, and stunnel will transmit data across through haproxy to you redis nodes. And on the otherside you will have logstash-indexers reading from local stunnel, which contact redis for data.