Re: z/OS DFS SMB Performance

Smith, Sean M wrote:

Yes I believe that is the case. We are not using z/OS for the VPN
service.

In that case you should notice similar speeds on same speed link, with or without VPN.
I know your non-VPN connection is LAN connection, probably much faster than VPN connection.
If possible try to connect via VPN locally and compare the speed with direct connection.
Don't compare i.e ftp speed to SMB speed, SMB is not fast.

How can VPN influence SMB performance (my guesses):
1. Different (smaller) IP packets causing worse performance.
2. Additional data in packets causing overhead: you SMB transmit 100kB, VPN transmit it as 130kB.
3. VPN devices are CPU-overloaded with encryption/decryption.
4. "VPN does not like SMB" <vbg> It Windows-like technology...

--
Radoslaw Skorupka
Lodz, Poland

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