"iSCSI lets everyone leverage the developments of generic ethernet switches, routers, tunnels and bridges rather than having to develop new Fibre Channel ones from scratch."
One problem with this is the performance will be crap using existing ethernet host adapters. There are a few companies working on host adapters with TCP-offload engines. Putting the TCP packets back together and pulling them apart takes a lot of kernel/system CPU cycles and it severely slows the data transmission rates.
Initially, and probably for the next couple of years, host adapters or other hardware that can offload the TCP overhead from the system CPU will be very expensive (more than the current fibre channel HBAs) but overall not having to buy FC fabric switches from Brocade because you can use existing IP hardware infrastructure will be a cost advantage -- but not much. If anything, the prices for implementation will be close to the same for the next year or two and then it depends on how fast the FC stuff becomes cheaper and how fast the iSCSI stuff gets truly developed by hardware companies (Emulex, Qlogic, Adaptec, LSI Logic, etc.) whose R&D budgets are already squeezed tight by the current economic environment.
I works with multiple storage vendors' equipment and EVERYBODY tests using fiber-optic cables from the host/server to the switch/storage.
There are, however, a couple of storage vendors who run copper from the storage controllers to the actual disks.
The main issue with copper is length -- fiber-optic cables are the only media which can actually attain the distances specificed in the specification. (see the FC-PH spec for details)
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"iSCSI lets everyone leverage the developments of generic ethernet switches, routers, tunnels and bridges rather than having to develop new Fibre Channel ones from scratch."
One problem with this is the performance will be crap using existing ethernet host adapters. There are a few companies working on host adapters with TCP-offload engines. Putting the TCP packets back together and pulling them apart takes a lot of kernel/system CPU cycles and it severely slows the data transmission rates.
Initially, and probably for the next couple of years, host adapters or other hardware that can offload the TCP overhead from the system CPU will be very expensive (more than the current fibre channel HBAs) but overall not having to buy FC fabric switches from Brocade because you can use existing IP hardware infrastructure will be a cost advantage -- but not much. If anything, the prices for implementation will be close to the same for the next year or two and then it depends on how fast the FC stuff becomes cheaper and how fast the iSCSI stuff gets truly developed by hardware companies (Emulex, Qlogic, Adaptec, LSI Logic, etc.) whose R&D budgets are already squeezed tight by the current economic environment.
We'll see. NAS or SAN or iSCSI????
I works with multiple storage vendors' equipment and EVERYBODY tests using fiber-optic cables from the host/server to the switch/storage. There are, however, a couple of storage vendors who run copper from the storage controllers to the actual disks. The main issue with copper is length -- fiber-optic cables are the only media which can actually attain the distances specificed in the specification. (see the FC-PH spec for details)