Thanks to the DS1517+ built in encryption engine there's only a 14MB/s drop in performance writing an encrypted folder to the NAS. Reading the encrypted data back there's hardly any loss in performance.
When tested with the various workloads that the DS1517+ might be used for in a RAID 5 setup, the NAS shows strong and very consistent performance across the workload scenarios.
Somehow the benchmark results do not make a lot of sense to me ie looking at the throughput benchmarks most of them hover around 100 MB/sec despite the different RAID set-ups ie one would expect for example a noticeable difference between RAID-0 and RAID-5….
My guess is that you connected the NAS and/or workstation via a standard 1 Gigabit Ethernet to the Network and therefore the LAN became the bottleneck at around 100 MB/sec ie 1 Gigabit …
In a 10 Gigabit LAN with 5 HDs installed I would expect that you should get close to 400 – 500 Megybytes/sec (at least thats my experience with Synology although I am not familiar with this specific model, so there might be otehr bottleneckes in the specific set-up, also 10 Gigabit needs a little bit of tuning until you get good throughput).