LTO with Encryption Appliance

I'm considering the purchase of a Neoscale CryptoStor Tape appliance
for use with an Ultrium 4 tape drive (SCSI). The CryptoStor has an
Ultra320 interface and the U4 (IBM TS2340) is Ultra160. LTO-4 is
rated at ~120 MB/s native and ~240 MB/s compressed so the CryptoStor
should have no problem keeping up. Eventually though I will upgrade
to LTO-6 which is 270/540 MB/s. Assumming there are no other devices
on the SCSI bus and the best case scenerio with regards to
compression, could the CryptoStor become a bottleneck with the LTO-6
or do I need to consider only the native transfer rate? (320 is
between the native/compressed estimated transfer rates of 270/540 for
LTO-6)

Thanks

"Madcap" <madcap@jerryslab.com> wrote in message
news:1192830172.616479.122870@v23g2000prn.googlegr oups.com...
> I'm considering the purchase of a Neoscale CryptoStor Tape appliance
> for use with an Ultrium 4 tape drive (SCSI). The CryptoStor has an
> Ultra320 interface and the U4 (IBM TS2340) is Ultra160. LTO-4 is
> rated at ~120 MB/s native and ~240 MB/s compressed so the CryptoStor
> should have no problem keeping up. Eventually though I will upgrade
> to LTO-6 which is 270/540 MB/s. Assumming there are no other devices
> on the SCSI bus and the best case scenerio with regards to
> compression, could the CryptoStor become a bottleneck with the LTO-6
> or do I need to consider only the native transfer rate? (320 is
> between the native/compressed estimated transfer rates of 270/540 for
> LTO-6)
>
> Thanks

If it does do 320MB/s and when (if ??) LTO-6 makes it to the market then the
box will indeed become a bottleneck. Likely one of many...

You should ask Neoscale what encryption/decryption rate you can expect from
their appliance. The fact that is has an Ultra320 SCSI interface doesn't
mean the appliance is able to encrypt data at 320MB/s. Since they have Fibre
Channel based versions that are 2 Gbps FC, I wouldn't be surprised when
their top rate will be below 200MB/s. Ask them, and ask for references of
actual users.

Also, you are planning to start with LTO-4 which has encryption features
built right into the hardware of the drive. Do you really need to add an
external encryption system?

Rob

On Oct 20, 2:08 am, "Rob Turk" <wipe_this_r.t...@rtist.nl> wrote:
> "Madcap" <mad...@jerryslab.com> wrote in message
>
> news:1192830172.616479.122870@v23g2000prn.googlegr oups.com...
>
> > I'm considering the purchase of a Neoscale CryptoStor Tape appliance
> > for use with an Ultrium 4 tape drive (SCSI). The CryptoStor has an
> > Ultra320 interface and the U4 (IBM TS2340) is Ultra160. LTO-4 is
> > rated at ~120 MB/s native and ~240 MB/s compressed so the CryptoStor
> > should have no problem keeping up. Eventually though I will upgrade
> > to LTO-6 which is 270/540 MB/s. Assumming there are no other devices
> > on the SCSI bus and the best case scenerio with regards to
> > compression, could the CryptoStor become a bottleneck with the LTO-6
> > or do I need to consider only the native transfer rate? (320 is
> > between the native/compressed estimated transfer rates of 270/540 for
> > LTO-6)
>
> > Thanks
>
> If it does do 320MB/s and when (if ??) LTO-6 makes it to the market then the
> box will indeed become a bottleneck. Likely one of many...
>
> You should ask Neoscale what encryption/decryption rate you can expect from
> their appliance. The fact that is has an Ultra320 SCSI interface doesn't
> mean the appliance is able to encrypt data at 320MB/s. Since they have Fibre
> Channel based versions that are 2 Gbps FC, I wouldn't be surprised when
> their top rate will be below 200MB/s. Ask them, and ask for references of
> actual users.
>
> Also, you are planning to start with LTO-4 which has encryption features
> built right into the hardware of the drive. Do you really need to add an
> external encryption system?
>
> Rob

Thanks for the input Rob.

I haven't spoken with Neoscale yet but their literature claims "media
speed AES 128 or 256 tape encryption". They also mention
"integrated compression" but NOT "integrated compression at media
speed".

IBM doesn't offer the TS2340 with FC, only LVD SCSI or SAS. IBM does
not (yet?) offer an SAS adapter for my host system (iSeries aka AS/400
aka System i aka...) and the SCSI model doesn't support encryption.
They have the TS1040 with an FC interface but I think it requires a
library (will check with my IBM rep to see if that can be used as
internal drive on the 400). So I think it's either SCSI with
something like the Neoscale or step up to a library which IS offered
with FC or go with a non-IBM standalone LTO-4 drive w/FC and
encryption (if they exist). The real kicker is my DR vendor. They
will support a Neoscale solution for no extra charge but want an
outrageous annual fee to support the IBM libraries. I imagine that
their supporting a non-IBM solution will cost me as much or more than
what they're quoting for the IBM libs.

Being that I don't need a library, I can't justify the extra
investment, DR fees, and hardware maintenance of the TS3xxx libraries
unless it comes with a performance gain. The Neoscale and standalone
drive should be much less expensive. Not only that but I may get away
with just getting the Neoscale now and postponing the drive upgrade
for a year or so (using Ultrium 2 now).

What would be interesting is if I could backup using a TS3xxx library
and IBM's key manager and be able to export (and convert?) keys for
restore using my DR site's Neoscale and TS2340 . Something tells me
that isn't possible though.

The good thing is that my DR site already has the Neoscale and TS2340
so I can probably run some tests myself. They will likely give me the
time and resources for free if they want to sell me the hardware.

Back to my original question but forgetting about the encryption - if
the Neoscale were receiving uncompressed data from an LTO-6 at 240 mb/
s and were acheiving 2:1 compression, would my throughput to the drive
(also with U320 interface) keep up or would U320 become a bottleneck
since the effective transfer rate due to compression would exceed 320
mb/s?