Brocade has introduced pipelining technology for transferring data from a mainframe across a WAN and FICON (fibre connectivity) link to IBM and Sun virtual tape libraries. It says this can increase backup speed by up to 70%.
Mainframes can use FICON, a channel architecture, to transfer backup data to tape or to virtual tape libraries (VTLs). If compressed, the data can be sent across a wide area network (WAN) link but the latency of the link is much longer. Packets of data will be sent across the link and the next set of data held in a queue until successful receipt of the preceding packet is confirmed.
Too long a latency will convince devices at either end of the link that it is down. This limits the distances at which such remote vaulting can be implemented.
Pipelining breaks a communications link into stages and sends data across the link stage-by-stage. In a three-stage pipeline, three packets of data can be in transit simultaneously instead of just one, increasing the speed of the link.
Brocade’s M3000 and USD-X products are placed between the mainframe FICON channel and the wide area link, and also between the target virtual tape library and the WAN. When a mainframe sends out a packet of data the Brocade device confirms receipt and sends it on across the WAN whilst the mainframe sends the next packet out. If the transmission of a packet across the WAN fails then the Brocade box resends it using a copy stored in its memory buffer.
In effect, the mainframe and the virtual tape library devices are spoofed into thinking they are local to each other instead of being hundreds or thousands of kilometres apart.
Such pipelining increases link speed by 200% and the backup time to IBM’s VTS (virtual tape server), Peer-to-Peer VTS, or Sun/StorageTek’s VSM5 FICON-connected virtual tape libraries can be cut by almost 60%. It means remote vaulting can cross continental distances allowing for business continuity and disaster recovery operations between widely-separated datacentres.
Tom Buiocchi, Brocade’s global marketing vice president, says: “High-performance tape vaulting over distance allows customers to extend the affordability and reliability of tape to provide a robust and affordable business continuity solution for today’s largest global companies.”
That should increase the attractiveness of virtual tape libraries to mainframe users. Brocade’s tape pipelining, immediately available for Sun and IBM mainframe VTLs, works with all industry-leading tape, virtual tape, and enterprise backup software solutions.