Couchbase LITE Replication design(when network down and up / when Replication is stopped and started)?

Hi Folks,

Trying to understand this use case behaviour in Couchbase Lite and SGW.

1)Insert a big doci.e 10 mb, replication is ongoing and 5b is reached SGW.
2)Pull a big doci.e 10 mb, replication is ongoing and 5b is reached CBLite.
3)Now networks goes down and comes up or.
4)Replication is stopped and restarted.

On #3 and #4 what does replications module do?Does it

" Before it starts the transfer/Download does it do a full hash check to find out which parts of the file it needs to get/put.Hence not syncing available data?

Note:yet to analyse CBL logs or code work through.

Thanks
Nithin