10Gb Ethernet Alliance is Formed

Lucas123 writes "Nine storage and networking vendors have created a consortium to promote the use of 10GbE. The group views it as the future of a combined LAN/SAN infrastructure. They highlight the spec's ability to pool and virtualize server I/O, storage and network resources and to manage them together to reduce complexity. By combining block and file storage on one network, they say, you can cut costs by 50% and simplify IT administration. 'Compared to 4Gbit/sec Fibre Channel, a 10Gbit/sec Ethernet-based storage infrastructure can cut storage network costs by 30% to 75% and increases bandwidth by 2.5 times.'"

Re:Fibre only?

[sjhwilkes]

Not to mention 10 gig CX4 - which uses the same copper cables as Infiniband, and works for up to 15M - enough for many situations. I've used it extensively for server to top of rack switch, then fiber from the top of rack switch to a central pair of switches. 15M is enough for interlinking racks too provided the environment's not huge.

Re:Block storage?

[spun]

SAN is block storage, NAS is file storage. Simply put, if you send packets requesting blocks of data, like you would send over your local bus to your local hard drive, it is block storage. If you send packets requesting whole files, it is file storage.

Re:Fibre only?

[mrmagos]

Don't worry, according to the task force for 10GBASE-T (IEEE 802.3an), cat6 can support 10Gbit up to 55m. The proposed cat6a will support it out to the usual 300m.

Re:Block storage?

[Guy Harris]

SAN is block storage, NAS is file storage. Simply put, if you send packets requesting blocks of data, like you would send over your local bus to your local hard drive, it is block storage. If you send packets requesting whole files, it is file storage.

No. If you send packets requesting blocks of data on a region of disk space, without any indication of a file to which they belong, that's block storage. If you send packets opening (or otherwise getting a handle for) a file, packets to read particular regions from a file, packets to write particular regions to a file, packets to create, remove, rename files, etc. that's file storage.

Most of the file access protocols out there (NFS, SMB/CIFS, AFP, NCP, etc.) permit you to read or write particular regions of a file (they don't even have to be aligned on block boundaries; they don't require whole file access. That's NAS, not SAN.

There are protocols used on SANs that mix file and block access, e.g. the protocols used by Quantum's StorNext, where create, delete, rename, open, etc. operations go to a metadata server and involve files, but reads and writes are done directly to the disk blocks in question over the SAN (you ask the metadata server for information to let you know what blocks on the SAN corresponds to particular data within a file).

Channel bonding

[h.ross.perot]

Sigh, Aggregating 2 or more 1 GIG adapters does not give you 2 GIG of throughput. It is a sliding scale; the more you add the less total bandwidth you see. The safest bonding scheme uses LACP; Link Aggregation Control Protocol. This protocol communicates member state and load balancing request to the link member. 10G over copper will be a good thing for VM's. Sad; that the current crop of 10G over copper adapters do not approach 5 gig throughput; raw. Give the industry time; this it just like the introduction of 1 GIG from fast Ethernet. It took 2 generations of ASICs to get to what we consider a GIG card today.

Re:Bonding for Unlimited Bandwidth

[imbaczek]

802.3ad [wikipedia.org]

Re:Math on /.

[rdebath]

Modern ethernet 100Base-T switched or 1000Base-T can work to 100%. With the switched medium all the links run full duplex and packets for busy links are stored in memory like a router. With a good switch packets for non-busy links get 'wormholed' to the output before they arrive (arrive completely that is).

Normally this means that modern lans won't lose any packets; if your lan is losing packets you have a hardware problem. Perhaps you have an unswitched hub somewhere or a seriously overloaded switch that's running out of memory. But even a low spec switch that can't keep up with the net speed shouldn't lose anything, it should just block the senders till it can deal with the data.

In fact 10Base-2 (cheapernet) was the last ethernet standard that that you couldn't avoid congestion collapse.

Re:Fibre only?

[segfaultcoredump]

I guess that is why we run 50/125 multimode everywhere. the 62.5 just didnt cut it anymore for higher bandwidth applications :-)

Maybe you are thinking about 9micron singlemode fiber?

Re:Math on /.

[gallwapa]

CSMA/CD still applies, except for the fact that on a switched architecture your collision domain is only a single port on the switch. Therefore the problem will lie between the switch and the device itself.

CSMA/CD is still important in modern ethernet networks, due to the fact that some devices do not properly auto-negotiate. Some devices doesn't obey the RFC's for interpacket spacing in an effort to improve their throughput that can wreak havoc on networks.

In many cases, if a link fails auto negotiation it will default to a half duplex link, where CSMA/CD is of vital importance.

Re:Math on /.

[petermgreen]

BTW 10 gigabit ethernet has completely dropped support for half duplex links.