Teiid only uses Infinispan to cache the cache keys and references to data in the buffer manager.
To further what Ramesh is saying, the cache key for result set caching contains the user sql, so that may need to be secured in a WAN/Cloud deployment. The replication of data/buffer entries is done directly over JGroups, which can be secured as well. See the note at the bottom of the Infinispan security link that talks about using an ENCRYPT protocol. I believe SSL is also supported.