There has been a sea change on this in the last year or so. 2.5gbe is really starting to hit the market in a big way, multi-gig has gone from "why would you need that" to "in systems by default", and it did it all of a sudden. I did a mITX build on a B550 board last summer (so, not the super premium high-end boards) and all of the options I was looking at had 2.5gbe ethernet.
Going forward, both AMD and Intel have built 2.5 gbe controllers into their cpus and chipsets, so if partners want to use it, it's there. As such you will see it start to be rolled out even in consumer products over the next couple years. The initial rollout was hampered by a few "light errata" with intel's controller implementation (basically it didn't work at 2.5 gbit speeds at all, oops) but we're a couple gens into it now and it's going forward. AMD has one on their chips as well (if not faster, I want to say AMD has 10gbe in their dies for Ryzen Embedded usage).
(expecting it in a 2020-era product, however, is perhaps not reasonable, like I said this is something that has changed mostly in the last year or so. Although granted a Thinkpad is not a consumer product so maybe it should have been ahead of the curve. But I don't think multigig had penetrated even professional spaces that well in 2020, except perhaps 10gbe in certain high-end segments.)
The gotcha with multi-gig has always been switches, very few cheap switches existed and the ones that did were mostly SFP+ and not 10GBase-T (i.e. you either need new wiring anyway, or you pay $50 a set for SFP+ adapters). This is somewhat better with 2.5gbe, there are now some 8-port switches under $200, but it's still a long way from 1gbe where you can get a nice 8-port for like $25. Hopefully it is a matter of volume and prices come down over time.
I'm a little miffed that 10gbe got passed over - 2.5gbe seems like a half-measure, and the wiring argument isn't very compelling to me. If they implemented 10gbe you could always allow fallback to 2.5gbe if that's what the signal quality can support (many <10 meter Cat5e runs are good enough for full 10gbe anyway) and it's a much more significant step than 1->2.5gbit. And the economy of scale here is significant, if consumer stuff goes 2.5 then that's what gets made and 10gbit remains expensive.
Anyway currently I am eyeballing the Netgear MS510TXM - this does pretty much what I want in terms of giving me a few SFP ports for fiber links (or server usage - SFP does have lower latency), a few 10gbase-T links for consumer PCs with Aquantia 10gbit nics, and a few 2.5 gbit ports for consumer junk. At $500 it would be nice if it was a 12-port, but it checks most of the boxes at least.
I had know idea it was finally starting to appear on the scene - with even some WiFi adapters pushing past 1Gb, it's about time!
Still, as much as I'd like it myself, I can't imagine there is any push at all from consumers, and very little from prosumers. I guess it's a bit of a chicken and egg thing.
Yeah, to put it another way, consumers aren't going to notice the difference, and prosumers probably would rather have had 10gbe. 2.5gbe is an awkward compromise imo, where the only real argument for it is strict observance of the cat5e rating over very long runs (that aren't super likely in consumer usage anyway, and could be accommodated by 5gb/2.5gb fallback speeds).
It's not every day you need multi-gig, but it is very nice when you do end up doing something big that hammers your network hard. You do need to be serving from a SSD or a NAS, neither of which are particularly unusual anymore, but I guess for most consumers they don't really work with "their media" at all anymore, everything has transitioned to the cloud for average consumer. Everything is streamed, and if you want to back up a steam game or something, you just delete it and re-download it if you want it later.
Bet that kinda sucks for people in Canada or australia on super limited data caps though, it's kind of a weird US- and euro-centric perspective.
As a prosumer, it's a bit of a mentality change, but for things like photo or video editing, you don't need to have tons and tons of fast storage on your local machine, you can push it off to to your NAS and just manage it like the rest of your data, which is a huge convenience thing (in terms of backups, and in terms of capacity). 4-drive or 8-drive NAS can push a ton of data even if random isn't quite as fast as a SSD (and that's why files get cached in RAM anyway).
> Bet that kinda sucks for people in Canada or australia on super limited data caps though, it's kind of a weird US- and euro-centric perspective.
What?!? I live in Canada and have not had a data cap in over 10 years. They might exist for some ISPs but they are generally high enough that I've never heard anyone complain or get charged.
I wonder how practical it would be to have SFP+ slot in a laptop. I guess they are bulky comparatively, but you'd get great flexibility wrt. 10gbe. Power consumption might be bit of a problem though?
of course, but then you don't get the power advantages of copper SFP+ cabling. The 10gbase-t spec is the same spec either way, the reason it takes so much power is due to the length of the cables and the signal quality required of base-T cable, so it doesn't magically take less power because you run it through an adapter module.
(SFP has a limit of 7 meters for copper cables, I think it can go higher for active cables, but most people use fiber for longer runs)
If you just wanted to plug into a switch that was like 5 feet away, SFP copper cabling would actually reduce power a fair bit. Not really sure where fiber falls, but as far as copper, the problem is specifically the 10GBase-T leg, and if you include a 10GBase-T leg then you pay that power penalty regardless of whether it's via a native NIC or whether it's a SFP NIC with a module.
I do totally agree it would be a nifty idea though. It actually would bring down power for short connections, and a lot of laptop ethernet connections are "plug me into my desk switch" type use-cases anyway. Meanwhile, if you do want a longer connection, it doesn't limit your options because you can use a module.
But I suppose a lot of that has been subsumed into docks anyway. Thunderbolt 3 is absolutely fine for that hop to your dock. Related discussion but as a weirdo, I would actually rather have a more robust connector with longer distance support than Thunderbolt natively allows - if I could plug a cable and get 10 meters or so, that would solve some use-cases for me. Currently the only option is Optical Thunderbolt cables and everything I've heard is that they are absolutely flaky as hell and usually die after a year or so. I would love if I could use QSFP copper or something.
(my use-case is I want to have an external PCIe enclosure with the adapter for my Vive Wireless so the PC doesn't have to be in the room, but that would involve at least a 10 meter run for me realistically. Being able to run HDMI 2.1 over QSFP would also be neat because I could have my desktop run a 4K120 TV properly without having to have a dedicated HTPC there...)
Anyway back to SFP in laptops - you're right that it's pretty bulky. Even the "box" is big but it's also a very long connector physically, and the tab that protrudes even farther. The other thing that may not be immediately apparent is that it's not rated for all that many plug/unplug cycles. My QSFP cables have a "10 cycles" tag on them. Obviously they don't instantly die after 10 cycles, but still it's not something you are going to plug and plug every day for years. I don't remember if my SFP cables have one but I don't think it's significantly different. The SFP series are not a "consumer" connector, they are for servers that get racked once in a datacenter and then sit for 5 years, maybe have the cables re-organized once or twice.
It might well be something that you could fix with a "micro SFP" connector though. Slightly smaller box, much shorter, try to aim for higher cycle life. I think you would still retain a lot of the electrical benefits of SFP.
It's not very relevant for laptops, but SFP adapters also have an order of magnitude lower latency than base-T adapters. For things like your fileserver, it's preferable to use SFP if possible, that's why I mentioned I liked the Netgear MS510TXM above, 2 SFP links gives you one for your fileserver and one for a fiber link (to another switch perhaps), or you could do two SFP links and bond. There's some nice flexibility there.
Going forward, both AMD and Intel have built 2.5 gbe controllers into their cpus and chipsets, so if partners want to use it, it's there. As such you will see it start to be rolled out even in consumer products over the next couple years. The initial rollout was hampered by a few "light errata" with intel's controller implementation (basically it didn't work at 2.5 gbit speeds at all, oops) but we're a couple gens into it now and it's going forward. AMD has one on their chips as well (if not faster, I want to say AMD has 10gbe in their dies for Ryzen Embedded usage).
(expecting it in a 2020-era product, however, is perhaps not reasonable, like I said this is something that has changed mostly in the last year or so. Although granted a Thinkpad is not a consumer product so maybe it should have been ahead of the curve. But I don't think multigig had penetrated even professional spaces that well in 2020, except perhaps 10gbe in certain high-end segments.)
The gotcha with multi-gig has always been switches, very few cheap switches existed and the ones that did were mostly SFP+ and not 10GBase-T (i.e. you either need new wiring anyway, or you pay $50 a set for SFP+ adapters). This is somewhat better with 2.5gbe, there are now some 8-port switches under $200, but it's still a long way from 1gbe where you can get a nice 8-port for like $25. Hopefully it is a matter of volume and prices come down over time.
I'm a little miffed that 10gbe got passed over - 2.5gbe seems like a half-measure, and the wiring argument isn't very compelling to me. If they implemented 10gbe you could always allow fallback to 2.5gbe if that's what the signal quality can support (many <10 meter Cat5e runs are good enough for full 10gbe anyway) and it's a much more significant step than 1->2.5gbit. And the economy of scale here is significant, if consumer stuff goes 2.5 then that's what gets made and 10gbit remains expensive.
Anyway currently I am eyeballing the Netgear MS510TXM - this does pretty much what I want in terms of giving me a few SFP ports for fiber links (or server usage - SFP does have lower latency), a few 10gbase-T links for consumer PCs with Aquantia 10gbit nics, and a few 2.5 gbit ports for consumer junk. At $500 it would be nice if it was a 12-port, but it checks most of the boxes at least.