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Comment by TheAdamist | Hacker News Reader

Other than reusing existing cables, how this is going to be cheaper than 10GBASE-T isn't clear to me.

Can they make switches & NIC's reasonably priced compared to 10G? If so what in the spec allows them to do that?

This technology isn't designed to compete with 10gbit in the datacenter. 10GBASE-T has very strict requirements that can't be met by most installed cable plants except for very short runs, and as a result is almost exclusively used within a single room/datacenter. The Netgear switch they call out near the beginning of the article hints towards the source of the problem: 802.11ac Wave 2 now allows for just over 2gbps of throughput for current-generation APs.

Access layer switches are generally already backhauled with 10gbit where necessary, and even if they aren't running a fiber pair into the IDF doesn't cost a lot. There is little call for 10gbit to the desktop for most fixed-station users. APs on the other hand are getting swamped and they are widely distributed and are almost universally connected into the access layer with cat5-class cabling. Existing Wave 2 devices on the market solve this by aggregating two cat5 cables but this isn't ideal and often times still requires running new cables.

The goal then is to provide a swap-out replacement for existing APs and switches over existing cable plants. Cisco, et al want there to be no friction to finally talking their customers into an upgrade for their existing gigabit switches, and Wave 2 provides a nice incentive to do so, but only if you can get that bandwidth to the APs when nobody is interested in running new cables across the entire building.

Hence, NBase-T.

Anecdotally, from the perspective of an ISP, I almost never see 10GBaseT. Even in the datacenter. I see a great deal of singlemode, and some special multimode cables for 100GbE intra-building links. And of course cat5e/cat6 for stuff like 1000BaseT top of rack switches to ordinary dedicated servers in colocation. If you tried to run cat6a or cat7 cable in some facilities here (or order your technicians to do it) you'd be laughed at and shamed by your peers for being wasteful of overhead cable tray space, and lacking the foresight to predict low cost 100GbE optical in a few years.

I've mostly seen 10GbaseT from top-of-rack to the server. Sure, you could go twin-ax copper too, but if your servers have 10GbaseT as an option, no need to go to SFP+. That's great if you're doing rolling upgrades of networking gear ahead of server refreshes so you need to support 1GbaseT at the same time, too.

I work as a datacenter consultant and I can count on one finger the number of customers I've seen deploy 10GBASE-T at any scale (and they aren't a customer I would hold out as an example for how to do anything right). As others have mentioned, 10gbit is almost exclusively deployed using optics or direct-attach twinax.

Your point about upcoming fiber technologies is well taken and I hadn't considered the situation in that light.

I wouldn't discount the potential huge cost wins of reusing existing cables, both from a cabling installation cost perspective, and from the ability to perform a phased migration. Even at cost parity w/ 10G Ethernet it would still be a net savings versus re-cabling.

The cost to re-cable an old building that has cat5e trapped in the walls and inside suspended ceilings is immense. There are a LOT of buildings that were cabled with ordinary cat5e UTP by low voltage contractors in the 1999-2002 era.

In theory there's less signal processing required for the lower throughput, but I doubt that translates to much savings in practice (and the Aquantia PHY still supports 10G mode so there's no savings there). The price may come down due to higher volume, though. The perception that 2.5G/5G is only for APs may mean that few or no NICs will ever be released.

Everything can be a bit slower and I think it is using a simpler encoding scheme on the wire, but even if that doesn't translate to a noticeable price difference on switch ports it still has a lot of benefit for the target market (which for now is pretty clearly wireless). 10GbE switch ports are cheap in comparison to large-scale cabling changes, or even worse running power to all those spots served by PoE before.

My employer still runs a 100Mbit network. Which is actually fine since the network drives top 3MB/s when everyone's not using them... At least they upgraded me from Windows XP last month. It was kind of overdue, not because it wasn't supported, but rather because I had more RAM available on my smartphone than on my $2000 workstation.

I like to think the IT department sources our hardware on flea markets.

> I like to think the IT department sources our hardware on flea markets.

For the really old legacy systems, NASA actually searches (online) flea markets: http://www.geek.com/chips/nasa-needs-8086-chips-549867/

That raises interesting "chain of custody" problems if some of these chips are reprogrammable and are coming from obscure online resellers.

Why? It doesn't even save money to use 100Mbit. You could argue staying on XP is actually costing more money.

Bureaucratic processes, low work standard, "good enough for the business". IT in a large financial company is a pretty appalling thing to observe. Everything that would take minutes to fix in a small organisation is taking years.

For instance the network drives hang regularly, sometimes for several minutes. That affects everyone on the floor. Because of a bug in Windows that was never fixed that also causes windows to hang for minutes, basically when it happens it is coffee time. Everyone I know in the organisation is affected, and has been for years. One would have thought that IT would do something about it, not the least because they must experience that themselves. That's counting without the "I don't give a shit attitude" that I pretty much always see in that part of the organisation.

It's not about money. If we need to make even the most minor changes, it becomes multi-year projects costing millions. As far as I can tell these millions are spent in project managers who understand neither the tech nor the business and ensure that the maximum amount of confusion is maintained. They are spent on paying salaries matching industry standard to bottom of their class developers who were not smart enough to work for google or facebook, and have no idea of what they are doing. Some of the things I see are pretty shocking. I faced developpers who are litteraly mild amateurs. And I would say developers are the "elite" of the IT crowd in these organisations.

Outsourcing didn't help with the I don't give a shit attitude. I doubt that the fact that a guy in London has to make 10 unecessary clicks everytime he needs to do something frequently, or has his computer completely unusable for minutes affects much a contractor in Bangalore. One would assume that a guy who would actually meet his "victims" would have a little more compassion, but as thing stands these problems are very much virtual to these guys.

100Mbit can save loads of money if you're fine with used hardware. You can get old Dell Powerconnect 3548s for next to nothing and it's a decent managed switch for SMB use. They're cheap to the point where you don't care too much if they ever do break because you can easily buy double for very little cash and always have hardware on hand to replace anything.

I'm not saying it's worth it but if 100Mbit works for you and you're short on cash you can get decent managed switches for very little cash. Gigabit switches aren't really at rock bottom prices for somewhat obvious reasons.

From the article it sounded like PoE, general power consumption and cable length were the issues.

Quite right, but those points seem more like PR 2.5G/5G group. Does anyone really need PoE and >1GB speed? Or care that copper cable lengths are limited to 100M?

802.11ac APs need PoE+ and 2.5G. That's really the only purpose of the standard.

Not all 802.11ac APs. Just the more expensive dual radio/3x3 MIMO and dual band ones. Most 802.11ac ordinary APs never get anywhere near 650Mbps real world speeds. Not even 1000 Mbps by far.

When you start looking at things like higher cost Ruckus and Xirrus APs that might have four independent radios operating in one physical unit, on the far end of a 1000BaseT link and PoE, it absolutely can approach 1.5 Gbps aggregate throughput.

I think when you serve multiple users, it is much easier to serve up 1gbs bandwidth wirelessly.

The target is pretty clearly wireless. We are reaching a point in WLAN tech where a 1Gbit uplink is starting to become a bottleneck (especially if an AP is creating multiple networks, or one cable serves multiple APs, but in theory a single 11ac network can do >1Gb/s).

APs commonly use PoE, might be in locations where there is no external power available and are connected with lots of individual cabling in often awkward spaces.

I don't think this is meant solely for data centers, more like offices, branches and home where it'd be cheaper to simply replace the switch/NICs than to rewire the entire place where they're in the walls. The savings are in the labor costs.

The article mentions power usage, and I would bet cost is also a factor - this is the reason many cheap SoCs only have USB2. One day I'm sure the cost will be low enough such that it will start appearing on "prosumer" equipment, then filter down.

However sometimes cost isn't the only factor, like in the case of two-pair gigabit https://en.wikipedia.org/wiki/Gigabit_Ethernet#1000BASE-TX.

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