Seems very limited if you can't get any switches that support 2.5GbE. Makes more sent to just go the full 10GbE route, though 10GbE switches are still very expensive.
Anybody recommend a better option than the Ubiquiti ES‑16‑XG[1]. Unfortunately most of the ports are SPF+ with only 4 ports being RJ45 10GBASE-T.
IIUC, the 2.5Gbase-t will work w cat5e cables, which is the highest signalling (or lowest cable spec) to fulfill building out a network. If you’re stuck w or otherwise committed to Cat5e, 10GbE isn’t an option. I guess it’d be a case-by-case decision whether that’s a blocking consideration...
In practice a lot of Cat5e cabling can support 10Gbe up to ~40m.
I guess the standards folks are hoping future equipment just supports 2.5Gb, 5Gb, and 10Gb then auto-detects the link quality and scales to whatever the cabling can support.
It’s really odd to me that 2.5G was seen as the next logical consumer step forward in Ethernet tech. Especially since “consumer” grade 10G cards have been available for some time.
Granted, I’m a bit out of the consumer use case for this stuff since I’ve transitioned my home to 10G fiber (in many cases easier to run and cheaper than 10G copper Ethernet cable).
For those confused as to why this exists, it's about cabling. It simply isn't possible to run 10Gbase-T over most existing structured cabling. Even with new cabling the network closet is often too far away. But 2.5GbE works in many situations.
If you're doing new cabling go multimode OM4 fiber. It isn't that expensive (buy factory terminated, use MTP trunk patching) and it supports stupendous data rates.
Thanks for the first hand China knowledge. The patch cable price is about a fifth of what I last paid for locally made and large qty (>100), but that was a couple of year ago. You can buy probably the same cable for US$5 here:
https://www.fs.com/products/40220.html?currency=USD
But most US retailers (BlackBox, Amazon, many others) seem to be price gouging massively, US$30 range.
I just read https://baike.baidu.com/tashuo/browse/content?id=82a3cad5ed1... which is hilarious in the Google translate version, containing many strange wrong takes on Western culture. It seems partially inspired by https://en.m.wikipedia.org/wiki/Mods_and_rockers but not a straight copy, more like a content for hire piece with extra moralising. Makes China seem very like the West in the late 50s. The site seems very much about product placement too. IDK if it's because I'm from outside but I didn't see any edit links (not that I can write anything except the most basic Chinese, and by hand because it was a long time ago).
Yes, for "just above 1G, and must reuse existing copper wiring, and both sides take PCIE", the card from the article will do. But it's a pretty narrow use case.
I agree with the notion of using fiber. I would certainly stay away from hardwired copper NIC's for anything except 1G, especially rarity ones like the one in the article. Rather, get 10G NIC's with SFP+ cages. Doesn't have to be a pricey Intel card, the cheap Melanox ones are acceptable for most users.
I disagree about OM4. If you're doing new fiber runs, singlemode (OS2 fiber) is the way to go. It's not really expensive anymore. But yeah, OM4 rather than OM3 for all fiber runs (for back to back patches, it doesn't matter ofc).
(Also, since we're talking about fiber networks... my personal lessons learned are: buy reflashable transceivers, especially when that's the difference between having DDM (Digital Diagnostic Monitoring) on all long runs and running it blindly. Standardize on a connector, hopefully LC. Be consistent which side TX and which is RX. Keep a 100-pack of dust caps around. And clean your fibers before inserting, especially patch fibers that get thrown around (they can look pretty bad on the fiberscope). Don't bother with Direct Attach Cables. Stay away from NICs with fixed 10G-Cu ports. Visual fault locators are cheap. BiDi SFP's are wonderful in one-fiber-run-broke or need-another-link-now type emergencies, so keep a few in reserve. And lastly, since all of this costs money, it's easier to beg for reimbursement than to ask for a purchase order.)
Hmm, lots more transceivers support multimode (not just Ethernet, serial/video etc) and a lot cheaper too. Direct attach is the only way to go for in-rack, both cost and cooling effects. Probably not the best in an office environment though.
In the desktop, QNAP recently released 8/12 port SFP+/T switches starting at US$500, which is the sort of pricing that will push this tech into small business. Probably buggy as hell at saturation and no features, but who cares, these are for doing occasional file transfers instead of passing around USB3 SSD drives.
I agree MM is more widespread, but I thought we were talking about new cabling (and I took that to include the transceivers). (Serial over fiber? Nice, didn't know that existed.)
Compared to the cost of actually running the fiber through the building, that's not too bad for trunks. As I said, I don't mind multi-mode for the last hop, which is where price is a larger concern due to quantity. And in organizations where OEM pricing is used as baseline, relative to that a resourceful admin can go to single mode and still come out ahead (it's not a fair comparison, but reality in some places). Sure, things are probably different in an actual DC.
Direct attach is certainly cheaper (at first), but it can be a hassle compat wise, and I've never had quite the right length available. I can't speak to cooling, that's never been my department.
Every SFP adds about 1W, but 10Gb-T ports are particularly thirsty, they were 5W when first introduced, still in that ballpark. It all adds up.
Another reason to prefer fiber/DA is 10Gb-T has shit latency, it has a modem doing QAM, hence the power consumption. Probably only relevant for HPC or HFT, but just inelegant.
22 comments
[ 3.0 ms ] story [ 55.0 ms ] threadAnybody recommend a better option than the Ubiquiti ES‑16‑XG[1]. Unfortunately most of the ports are SPF+ with only 4 ports being RJ45 10GBASE-T.
[1] https://www.ui.com/edgemax/edgeswitch-16-xg/
I have an 8 port SFP+ 1 port Gbe switch and it works well for a homelab.
I guess the standards folks are hoping future equipment just supports 2.5Gb, 5Gb, and 10Gb then auto-detects the link quality and scales to whatever the cabling can support.
Granted, I’m a bit out of the consumer use case for this stuff since I’ve transitioned my home to 10G fiber (in many cases easier to run and cheaper than 10G copper Ethernet cable).
[0]: https://en.wikipedia.org/wiki/10BASE5
[1]: https://en.wikipedia.org/wiki/10BASE2
If you're doing new cabling go multimode OM4 fiber. It isn't that expensive (buy factory terminated, use MTP trunk patching) and it supports stupendous data rates.
Someone should make https://en.wikipedia.org/wiki/OM4 redirect to https://en.wikipedia.org/wiki/Multi-mode_optical_fiber via #REDIRECT [[Multi-mode_optical_fiber]]
Can't log in right now due to China-ness.
- Is there a VPN that allows you to experience the GFW from inside China?
- Is there a Chinese equivalent to Wikipedia yet, i.e. non-profit & editable, or is it just the commercial and govt versions?
Good question, I guess they don't see foreign users as a real market.
What is the RMB price for e.g. 2m OM4 patch?
USD$3.5
Is there a VPN that allows you to experience the GFW from inside China?
Maybe. Anyway it sux.
Is there a Chinese equivalent to Wikipedia yet, i.e. non-profit & editable, or is it just the commercial and govt versions?
Many wikis but generally only Baidu Baike is popular. https://baike.baidu.com/
But most US retailers (BlackBox, Amazon, many others) seem to be price gouging massively, US$30 range.
I just read https://baike.baidu.com/tashuo/browse/content?id=82a3cad5ed1... which is hilarious in the Google translate version, containing many strange wrong takes on Western culture. It seems partially inspired by https://en.m.wikipedia.org/wiki/Mods_and_rockers but not a straight copy, more like a content for hire piece with extra moralising. Makes China seem very like the West in the late 50s. The site seems very much about product placement too. IDK if it's because I'm from outside but I didn't see any edit links (not that I can write anything except the most basic Chinese, and by hand because it was a long time ago).
I agree with the notion of using fiber. I would certainly stay away from hardwired copper NIC's for anything except 1G, especially rarity ones like the one in the article. Rather, get 10G NIC's with SFP+ cages. Doesn't have to be a pricey Intel card, the cheap Melanox ones are acceptable for most users.
I disagree about OM4. If you're doing new fiber runs, singlemode (OS2 fiber) is the way to go. It's not really expensive anymore. But yeah, OM4 rather than OM3 for all fiber runs (for back to back patches, it doesn't matter ofc).
(Also, since we're talking about fiber networks... my personal lessons learned are: buy reflashable transceivers, especially when that's the difference between having DDM (Digital Diagnostic Monitoring) on all long runs and running it blindly. Standardize on a connector, hopefully LC. Be consistent which side TX and which is RX. Keep a 100-pack of dust caps around. And clean your fibers before inserting, especially patch fibers that get thrown around (they can look pretty bad on the fiberscope). Don't bother with Direct Attach Cables. Stay away from NICs with fixed 10G-Cu ports. Visual fault locators are cheap. BiDi SFP's are wonderful in one-fiber-run-broke or need-another-link-now type emergencies, so keep a few in reserve. And lastly, since all of this costs money, it's easier to beg for reimbursement than to ask for a purchase order.)
In the desktop, QNAP recently released 8/12 port SFP+/T switches starting at US$500, which is the sort of pricing that will push this tech into small business. Probably buggy as hell at saturation and no features, but who cares, these are for doing occasional file transfers instead of passing around USB3 SSD drives.
https://nascompares.com/2018/04/12/unboxing-the-qsw-1208-8c-...
Pricing-wise, what I meant is:
$18: 10G-SR (MM): https://www.fs.com/products/11552.html
$24: 10G-LR (SM): https://www.fs.com/products/11555.html
Compared to the cost of actually running the fiber through the building, that's not too bad for trunks. As I said, I don't mind multi-mode for the last hop, which is where price is a larger concern due to quantity. And in organizations where OEM pricing is used as baseline, relative to that a resourceful admin can go to single mode and still come out ahead (it's not a fair comparison, but reality in some places). Sure, things are probably different in an actual DC.
Direct attach is certainly cheaper (at first), but it can be a hassle compat wise, and I've never had quite the right length available. I can't speak to cooling, that's never been my department.
Every SFP adds about 1W, but 10Gb-T ports are particularly thirsty, they were 5W when first introduced, still in that ballpark. It all adds up.
Another reason to prefer fiber/DA is 10Gb-T has shit latency, it has a modem doing QAM, hence the power consumption. Probably only relevant for HPC or HFT, but just inelegant.