HomePNA Achieves 320Mbps With Copper

illeism writes "Ars Techinca is reporting that the HPNA has made a significant stride in copper speed. From the article: 'The HomePNA Alliance, backers of a networking spec that works over coaxial or twisted pair wiring, has announced the release of the HPNA 3.1 specification. The big news comes in the form of a speed jump from 128Mbps to 320Mbps, which pushes it above competing networking standards HomePlug AV and MoCA (Multimedia over Coax) for the title of fastest networking tech outside of gigabit Ethernet and makes it a more attractive option for triple-play providers.'"

Re:What?

[Anonymous Coward]

Using legacy hardware in place in your home, such as coax or existing twisted pair.

Re:What?

[Kenja]

"What was wrong with gigabit ethernet?"

It requires CAT-6e certified twisted pair cables and wont run over existing house wiring.

Re:What?

[Anonymous Coward]

Not all houses are Cat5/6 wired (non-slashdotters) or want wireless. It's an alternative because you're taking advantage of existing wiring.

Re:Erm....?

[York the Mysterious]

You're assuming you can wire for Gig Ethernet. Many people out there have extensive installations that barely work with 100mbit. For instance the building I'm in was built in 1992 and wired for Ethernet EXCEPT (a big except) the installers stables the cabling the studs. Won't make it above 10meg and even 10 meg has errors left and right. The building had to be rewired so we could go 100Mbit, but that's 500 drops in 4 different structures with 4 wiring closets to pull back to. Stuff like this is a big deal for colleges. There's plenty of colleges that only have their internal phone lines the the rooms and are delivering internet connections via DSL technology from their closets. Schools with 2000 students on campus and sometimes in buildings on the historic registry. They REALLY want to be able to use that existing infrastructure to deliver a high speed connection.

GigE works fine over Cat5E wiring

[davidwr]

However, distance is severely limited. It works in a game-room just fine though.

I wouldn't recommend whole-house GigE with Cat5e. It might work, but only for a sufficiently small value of "house."

Re:But whats the latency?

[Fnkmaster]

Eh? A round trip through two HPNA 2.0 bridges adds about 2ms of latency to a packet from my empirical observations.

While I obviously wouldn't use a home networking standard for ultra performance critical networking applications, the latency of HPNA 2.0 is not something I ever perceptually notice, and I use it every day.

Re:GigE works fine over Cat5E wiring

[cheater512]

Guess what I'm using right now. :)

Yep. Gigabit over Cat 5e. Our entire house is wired up with the stuff.
I've maxed it out at 60MB/s before my CPU hit 100%.

Its not a small house either. The strech of cable my computer has to the server must be at least 10-15m long.
No packet loss, great ping and way too fast. :D

Re:GigE works fine over Cat5E wiring

[nixman99]

However, distance is severely limited. It works in a game-room just fine though. I wouldn't recommend whole-house GigE with Cat5e. It might work, but only for a sufficiently small value of "house."

For us commoners with houses under 4,050 m^2 (40,000 ft^2)*, cat5e [wikipedia.org] works fine.


* numbers based on 90x45 meter single story house, centrally-located core switch/router, and 65% efficiency of cable pulls.

Re:Erm....?

[GigsVT]

Uh, that's simply not correct. Analog phone is 2 wire, the audio signal is just superimposed over the DC bias, it's all done on two wires.

Re:Erm....?

[Anonymous Coward]

Uhhh... no.

The other two lines are traditionally used for a second line (or something else, like this HPNA technology). Power is modulated over the first pair (red/green) along with the voice signal. Google will enlighten you. If you only have one phone line, the black/yellow pair is totally unused.

Want more proof? (Assuming you only have one phone line in your house) Go out to the box where the phone comes into your house and you'll see that the black/yellow pair are either not connected to anything at that end, or if you disconnect them your phones will still work fine.

Want even more proof? Many (single-line) phones have only two prongs in the RJ-12 jacks on them... how does that power get to the phone if it only has prongs for the red/green pair?

Re:Erm....?

[Sj0]

Many people have taken issue with your first comment, but let me take issue with the second, lest I simply parrot the masses.

The phone is actually a single massive loop, which is terminated at the phone company central office. When the phone is on the hook, a very high voltage DC potential just sits there. When the phone rings, the central office sends an AC voltage over the DC carrier wave, which actuates the ringers in the phones. When the phone is picked up, the mic and headphone piece close the DC circuit. The Central office then detects the current (Which is very small compared to the voltage because it's being sent through kilometers of phone line) and switches to "off hook" mode.

Now, the reason this is at all relevant is DSL signals also live on this set of lines. That's why you need to install line filters in your house. HOWEVER, the DSL line can't be a low resistance device like the telephone, or your phone would be off the hook whenever you plugged your DSL modem in. Since the DSL modem would have to be a high impedance device capable of sustaining the massive DC voltage mentioned earlier, I know that 24VDC wouldn't hurt a DSL modem, and even in the worst case scenario of a 120VAC line connected directly to the phone (and why exactly would phone connectors be so tiny, with so little protection from electrocution or short circuits, if a 120VAC line voltage was present?), I'm pretty sure the DSL modem still wouldn't care, since the phone ringing voltage is about 90VAC. Some day I'll have to grab an old DSL modem and test my theory regarding the 120VAC, but I don't need to regarding the 24VDC. The line voltage used to test whether a phone is off the hook or not is about twice that.