2. SRDF – or, Symantic Remote Data Facility. This replicates data from different cities (for example). You can have 3 or more data centers replicating symaltaneously. They are working more with ORCL and MSFT here. Currently, he says that all competition is only at point of doing 1 replication symaltaneously. What that means exactly, I have no clue. Would love to hear more opinions on this here?????
Thanks, Pigboy.
One of the two beta sites for SRDF over IP was MCI. SRDF over IP is based on CNT's SAN over IP technology. When the SRDF over IP product was announced last year, there was a ZDNET article that quoted MCI as saying that they were already working with EMC on directory and policy services so that MCI could basically backup from disk arrays anywhere in the world on its advanced IP network. This would allow MCI, of course, to streamline the data management model used for internal purposes and for its corporate data services. From the technical description in your narration, the ability to replicate data simultaneously (synchronous mirroring) at multiple sites is part of that data management model. As you know, synchronous mirroring is very sensitive to latency, which is the time it takes a signal to go from point A to point B. It also requires a very reliable box and director switches because of the parallel operations inside the source and target disk arrays that have to occurr in a highly coordinated fashion (with automatic failover) to move the data around. Right now if you look beyond the specmanship, only EMC, Hitachi and IBM currently have the mature disaster-tolerant boxes for this type of large scale application and the gap between EMC and IBM/Hitachi is even wider than the gap between IBM/Hitachi and the other server vendors. Compaq, for example, has a remote mirroring solution that uses the same underlying technology from CNT, but do not quite have the same capabilities as EMC's SRDF which EMC started to develop in 1994.
This is a case study from the CNT website describing the transatlantic mirroring milestone that EMC/CNT recently achieved that gives you an idea of the degree of difficulty involved.
cnt.com |
