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Fibre Channel Standards, Speeds and Feeds, and Generation "X"

Mar, 27, 2013 Hi-network.com

Okay, I have a confession to make.

I've been somewhat amused by Brocade's recent "Gen 5" Fibre Channel campaign. After all, the idea that "we're going to simply call 16G Fibre Channel somethingotherthan 16G Fibre Channel and pretend that people will not figure out that it's really just 16G Fibre Channel" is, well, amusing!

Youmustgive credit where it's due: it's brilliant! How else can you convince an entire market to ignore the very obvious comparison between 16GFC and 40GE? For that matter, how do you deal with the fact that not only are there (currently, as of this writing) no major storage manufacturers with 16G FC arrays, but that even when you get them you've only got about 33% more bandwidth on the network than 10G FCoE?

Marketing Versus a Standard

I started to realize that maybe my amusement was going to be short-lived when I read an article from Chris Mellor in The Register about "Brocade's Fat Pipes." It's not surprising that Brocade would be pushing Fibre Channel more than Fibre Channel over Ethernet, as reported in the story. (Yeah, likethat'sa surprise!) After all, Brocade has less than 1% of the FCoE switching market, according to current analyst reports. Why would they bother to promote something that isn't their strong suit? That's like asking Microsoft to comment on Apple's iPhone in 2007. What do you think they're going to say?

Even so, it was this paragraph with which I had major issues:

Faster Fibre Channel is coming with a 32Gbit/s standard being developed, the Gen 6 standard. The International Committee for Information Technology Standards (INCITS) T11 Technical Committee is working to finalise the standards for this by the end of 2013. Brocade claims technical leadership of this committee and says it has already initiated research and development for 32gig Fibre Channel technology. Vulture Central suggests we might see initial product appear in mid to late 2014.

This is a huge problem, because there is no such thing as a Gen 6 standard. To conflate Brocade's marketing campaign with a standard is an outright falsehood. While it is true that Brocade holds the chair of the INCITS T11 Technical Committee, Mellor's reporting implies that Gen "6" is being promoted within the standards body. However, this simply isn't true.

In fact, it runs contrary to the INCITS antitrust guidelines:

Sensitive Topics

With rare exceptions that should be made only upon the advice of INCITS counsel, there should never be discussion of the following topics at any INCITS or an INCITS subgroup meeting:

  • Any company's prices or pricing policies;
  • Specific R&D,sales and marketing plans; [emphasis added]
  • Any company's confidential product, product development or production strategies;
  • Whether certain suppliers or customers will be served;
  • Prices paid to input sources; or
  • Complaints about individual firms or other actions that might tend to hinder a competitor in any market.

From a marketing perspective, Brocade is free to say whatever it wants, of course. If they wish to bend reality a bit, it's their prerogative. The argument is made that this focuses on value rather than speeds, but it's not really clear how: the naming criteria for these generations is based on the speeds, which can handle all of the various features as described in different standard documents.

Brocade makes the claim that customers are looking for a more holistic solution (a view of which I've long been a proponent!), but when you narrow the topic of conversation down to a single storage protocol it seems far more straightforward.

I disagree that speed isn't top of mind when comparing 8GFC to 16GFC to 32GFC because the feature set is exactly the same from one speed to another. That is, when we change the physical layer of Fibre Channel the upper layers of the protocol don't necessarily change. In fact, it's because Fibre Channel uses a layering system (similar to the OSI model, for instance), that we can modify the speed of a link without affecting other features of Fibre Channel.

Look at it this way: the T11 Technical Committee of INCITS is broken down into different working groups:

  • T11.2 Physical Variants
  • T11.3 Interconnection Schemes

Inside these different working groups there are several different committees, each working on various projects. Some have to do with management, some have to do with physical speeds, some have to do with switching, some have to do with security, etc. But apparently Brocade wants to cherry-pick what it wants to include and what it doesn't:

A little from here, a little from there...

What's more, Brocade claims that their new "Generation" of Fibre Channel switches (which makes far more sense if you're talking about a product line than a protocol) includes proprietary features that are not part of the standard. To that end, if Brocade wants the "ecosystem to follow," they may have shot themselves in the foot.

Fibre Channel Standards and the Gen n Problem

Because there are proprietary features in Brocade's "Gen 5" campaign, the fact that The Register is promoting this as a standard and that Brocade is driving it as such, is problematic at best.

One of the things about standards is that they provide a means to determine what can be done and how a standards-based solution can be implemented. Because of this, the standards themselves allow for testing criteria to measure against. That is, it is possible for a third party testing group to read the standard doc, understand how something works, and then independently measure whether or not a vendor's claim of compliance is truthful (or not).

As we can see, though, Brocade's usage of "Gen 5" and "Gen 6," while excellent marketing, is too arbitrary to measure any realistic qualification or testing criteria. How do you know that something is Gen 5? Who makes that determination? Brocade? Well, we've seen how well that matches up with the actual standards, haven't we?

Imagine that you built trains for a living, and different railroad lines had different width tracks (this happened, by the way, in the US in the 1800s). You would much rather prefer to build the widths of your trains to a standard size so that you could run on any track, right? Imagine a company that says they've standardized on the "next generation of tracks" but didn't actually follow an agreed standard? Hilarity ensues.

If a vendor wishes to claim that they adhere to a standard, they must identify where deviations occur, if such deviations exist. For instance, on Brocade's FCoE VCS switches they support the FC-BB-5 standard except when dealing with ISLs. In their VCS FCoE data sheets, for example, they call this out specifically as requiring Brocade's FCS technology as opposed to FC-BB-5's VE_Port technology.

And of course, there's nothing wrong with that from a standards point of view. They claim "FC-BB5 [sic] compliant Fibre Channel Forwarder (FCF)" which we can assume (rightfully so, I think) that the FCF handles fabric and FLOGI duties according to the spec. Works for me.

What does this mean in the 'real world,' though? Take a look at it from a potential customer's perspective:

Suppose I'm a government vendor and need to determine if bidders on networks can interoperate because it's part of my charter, and I want to avoid vendor lock-in. How does this solution accomplish this? Generally I look to standards-compliance as my criteria, because there are good quantifiable tests that the standards provide for ensuring that vendorsactuallydo what they say they do.

At the same token, how do they permit new vendors to bid on contracts that wish to upgrade/expand existing networks? What happens if a company goes out of business? How can a customer move to a new vendor (i.e., "product portability")?

In short, what good is a standard that isn't, well, standard?

Why Create Confusion?

Well, look at how difficult Brocade's job has got to be.

I mean, I've talked about this before, comparing the throughput of FCoE as we get into higher bandwidth speeds, and it's hard not to sit up and take notice that there are reasonable comparisons to be made -especially when you take into consideration thatmoststorage networking environments do not saturate classical 8G Fibre Channel lanes.

I know I put a graph up before about this, but look at the throughput differences between various storage protocols that are availableright now.When you take into consideration the encoding elements of the technologies, theactualbandwidth picture looks a bit different:

 

 

Okay, so that's what's available now. But 32G Fibre Channel is around the corner, right? It's going to give 40GbE a run for its money, right?right?

Umm...

 

Hmmm... well that's interesting...

 

Uh oh.

I see the problem here. After all, it's an issue that Cisco has been mulling over as well: Would people really want to move to 32G when it's likely that 100G FCoE will be available at roughly the same time, and 40G FCoE is availablenow?What possible use would people have for a dedicated 32G link for FC over a higher-bandwidth 40G link that can be used forany storage traffic?

It's a conundrum, to say the least. After all, the actual Fibre Channel stack isn't changing as the speeds increase. That is to say, there's nothing "special" with Fibre Channel as a protocol that adds anything of value when you move from one speed to the next.

In my head it's a conversation with the overachieving teacher's pet:

"I know! Pick me! Pick me! You gotta give 16G another name!"

"But wait, I wonder. Does it include all of Fibre Channel?"

"Naaaaah, ofcourse not. Only what we want it to include!"

"But it's only going to be stuff that's actually part of the standard, right?"

"Why on earthwould we want to do that? Throw in the kitchen sink, damn the torpedos!"

"Aren't people going to see through this?

"Hmmm, good point. I know, we'll convince people that it's such a great idea that it's going to bestandardized!"

Oops. Hold on a minute there, Sparkles. You've just gone a wee bit too far.

General Thoughts

As I mention above, you gotta give props to the "Gen 5" campaign. Personally, I see it as a somewhat dicey proposition considering the question of compatibility ("Will Gen 5 work with Gen 4? Can I mix-and-match Gen 6 switches with Gen 3 storage arrays and Gen 4 optics in my servers? Is there aninteroperability matrixI can look at? Wait, I needanotherinteroperability matrix? How do I know what's supported?").

Brocade says that their customers love the name change. If they do, they do; personally I tend to gravitate towards "more simple" rather than "more complex" as a general rule. That is, if I move from 8G to 16G, I know my throughput has changed, but that doesn't mean my fabric, my zoning my logins, or my designs have to change. With the new "Generation" moniker, how can I be sure?

I can't help but wonder how many conversations go something like this:

"Tell me about 16G Fibre Channel."

"Instead of that, let's talk about Gen 5!"

"What's Gen 5"

"16G Fibre Channel!"

"Um, okaaay..."

At the end of the day, of course, Brocade's done a fantastic job convincing people that the 16G FCelectronicsare the same thing as 16G Fibre Channel. Hell, they got Chris Mellor to advertise their entire marketing campaign for them. Pretty impressive, considering that they don't have 16G Fibre Channel actually running end-to-end, but they're already talking about32G!

Slow clap.

No, I'm not being sarcastic. I'm serious. This is impressive stuff here. It's one of those things that you see and think, "Daaaayum." If I had said to myself that I was going to be able to go out and sell an entire technology that wouldn't be able to be used as designed for overtwo years, I would have to wonder who spiked my drink. And yet, this is precisely what Brocade has done. Kudos.

At the same time, it's always been known that the runway was coming up short. Looking at the amount of bandwidth Ethernet is going to provide -and be used for more than just one type of traffic -it's a fight to stay pertinent.

 

Pretty soon you're talking real bandwidth!

Let's not start confusing the issue with standards, however. Thereis no"Gen 5" Fibre Channel standard, and there is no "Gen 6" Fibre Channel standard. Yes, advances are being made to specific parts of the standard, some have to do with speed, some do not. Some have to do with FCoE, some do not. What you cannotdo is cherry pick what is convenient to your marketing goal and confuse people into thinking that this is astandard.

Sorry, it just doesn't work that way.


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