IEEE Sets New Ethernet Standard That Brings 5X the Speed Without Cable Ripping (networkworld.com)

Reader coondoggie writes: As expected the IEEE has ratified a new Ethernet specification -- IEEE P802.3bz -- that defines 2.5GBASE-T and 5GBASE-T, boosting the current top speed of traditional Ethernet five-times without requiring the tearing out of current cabling. The Ethernet Alliance wrote that the IEEE 802.3bz Standard for Ethernet Amendment sets Media Access Control Parameters, Physical Layers and Management Parameters for 2.5G and 5Gbps Operation lets access layer bandwidth evolve incrementally beyond 1Gbps, it will help address emerging needs in a variety of settings and applications, including enterprise, wireless networks. Indeed, the wireless component may be the most significant implication of the standard as 2.5G and 5G Ethernet will allow connectivity to 802.11ac Wave 2 Access Points, considered by many to be the real driving force behind bringing up the speed of traditional NBase-T products.

Comments

Re:Why not coax?

[udif]

No.

802.11ac gets its speed via multiple spatial streams, using more than one antenna on both Tx and Rx sides.
Besides, the coax is 100% available all the time, while the wirelsss protocol is based on half duplex transmissions, and can only transmit to N clients at any given time (on each subband) when you have N antennas.

So for wired transmission you better use something else like MoCa.

Cat 6 cable finally has a use

[enriquevagu]

This new standard is very interesting: it employs the same coding and spectral density as 10GBase-T (6.25 bps/Hz), but it employs the available bandwidth (Hz) depending on the cable category: Cat.5e (100 MHz) can provide 2.5Gbps and Cat.6 (250 MHz) can provide 5 Gbps.

Interestingly, before this standard there was no practical use for Cat.6 cabling: any speed you could obtain using Cat.6 cable (1Gbps) could be also obtained using cat.5e, and if you wanted something faster (10Gbps) you needed Cat. 6A (500 MHz BW). This newly ratified standard finally gets some use from those extra MHz you have in Cat. 6, if you have installed it. It will be interesting to know if 802.3bz ports will be able to measure link bandwidth to adapt speed accordingly to 2.5/5Gbps.

Re:Will this need Cat 6?

[enriquevagu]

It can work over cat 5e for 2.5Gbps and over cat 6 for 5 Gbps. There is a nice description in the Wikipedia entry

Re:Will this need Cat 6?

[Shimbo]

Wasn't clear from TFA if this would work on Cat 5e, or if Cat 6 is required.

For 2.5Gbps, it's just fancier encoding, so 5e should be fine for the full 100m. Cat 6 gets you 5Gbps. You might get 5Gbps over a shorter length of cat 5E but there are no promises as far as I know.

Re:What about 10Gbps ethernet?

[David_Hart]

Wasn't 10Gbps a thing already?

Yes, it's a thing already; so if you have cat 6A installed everywhere, you can forget about it. However, there is a lot of installed 5E and 6 where it makes sense.

10 Gbps on copper has a limited range of about 15m, which is why its primary use is for servers in a data center.

The 2.5/5 Gbps copper standard will work up the 100m. It was developed largely for WiFi Access Points. 802.11ac Wave-2 with MIMO can go up to around 7 Gbps.

I've been working with this for a while

[AaronW]

I have been working with 2.5G for around a year now using a 2.5G physical interface chip from Aquantia that seamlessly handles everything from 100Mbps to 10Gbps including 1G, 2.5G and 5G. If the cable isn't too long I've run 10G over cat 5. Hopefully the prices will drop quickly once more companies support this standard since I just bought the cheapest 2.5G switch I could find, 8 ports for around $1200 for development purposes. It also interoperates fine with standard 1G equipment.

Aquantia is also nice is that unlike many phy chip vendors their phy SDK is free as in beer and is fully GPL and BSD compatible, though it will need to be re-written for the Linux kernel to follow the guidelines. I re-wrote it for U-Boot though I won't be able to push it upstream for a while yet. The chip I'm using even supports MACsec in hardware. There were two different 2.5G proposals, one from Broadcom and one from Aquantia. The Aquantia is the one that ultimately got accepted as the standard.

Re:What about 10Gbps ethernet?

[bobbied]

10GIGE needs CAT 6A cabling.

Actually, you only need CAT6 if you want to go the full 180 foot distance. Cat5e, depending on the cable's specifics will work just fine, though usually at a reduced maximum distance. That means my home's cat 5 will likely work up to 10Gig as all the runs are considerably shorter than 100 feet.