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[snadge]

the Gigabit port IS the Infinity Port though isnt it? - thats how they get away with that!! - 160Mbps+ Vectored VDSL , but your only gunna see 95Mbps of that cos of the 100Mbps LAN lol

[biohead]

Two Gigabit Ethernet ports (WAN and LAN), 5GHz 802.11n and a new faster processor make the BT Hub 4 the ideal partner for BT’s fastest Infinity fibre services providing a superfast connection that can be fully harnessed by a complete range of devices via the Hub’s superb connectivity options.

Two GigE ports. One WAN, one LAN 

Is the existing Hub3 like this (I don't have one to check)?

[kitz]

I really can't understand the mentality of putting 3x 10/100 and only one GbE

[snadge]

I really can't understand the mentality of putting 3x 10/100 and only one GbE

Cheaper?

Sent from my Sony Xperia Miro on Tapatalk

[kitz]

>>> Cheaper?


No that doesnt make sense either.  Surely the switch element would have to be Gigabit to serve the WAN and one LAN port.  So unless Im missing something why are the other 3 ports only 10/100. 

The Gb switch element is surely there anyhow (and has to be to support >300Mbps of 802.11n ?)
They are proudly claiming 802.11n, so we have the possibility of faster wi-fi than LAN depending on which port in use.
 
I havent looked into this so am happy to be corrected, but on home routers arent the ethernet ports 'part' of a switch which can route traffic correctly giving full bandwidth to each port, yet the wifi element (AP) acts more like a hub because its only able to share bandwidth.

So the only thing I can think of is the argument of processing power for GbE traffic!

If I am correct with the above, then surely the only reason for sticking in 3x 10/100 ports is purely to reduce/restrict the total amount of bandwidth being managed by the switching element in the router.

IMHO it isnt quite 'cutting edge technology' purely because of the lack of GbE ports, which is restricting the full capabilities of the LAN...  and therefore reducing processing power used by the router. 

I suppose the idea is if you want to use GbE then you add a separate switch letting that do all the traffic processing.

Rizla???  anyone else??   am I correct??

[Chrysalis]

it is cheaper I think but the amount they save will be tiny as the chipset needs to be gigabit capable for just that one port.  My guess is the savings are probably under £1, maybe £2 at absolute maximum.  BT are not unknown to skimp and save everywhere possible, and this shouts of that.

The practical use of it is stupid tho, so a switch with just 1 gigabit port is essentially a 100mbit switch, this leaves its use for FTTP infinity, which allows 1 machine only to get above 100mbit speeds.

I have seen one commercial router do something similiar, I believe the fritz 7360 has 2 100 ports and 2 gigabit.  However my guess is that wasnt done to save costs but more so to make people pick the 7390 over it, in other words to deliberatly make it worse than a higher cost model.  Of course the homehub doesnt have a higher cost model, BT just ship one version, so to me its a very silly design fault.

[burakkucat]

Two Gigabit Ethernet ports (WAN and LAN), 5GHz 802.11n and a new faster processor make the BT Hub 4 the ideal partner for BT’s fastest Infinity fibre services providing a superfast connection that can be fully harnessed by a complete range of devices via the Hub’s superb connectivity options.

Two GigE ports. One WAN, one LAN 

Is the existing Hub3 like this (I don't have one to check)?

Yes. I've just checked with both the HH3.0B and the BH3.0 that are lurking in my grotto.

[snadge]

I was just gunna say (but Bkat beat me..as always ) that the HH3b has 1Gb LAN port and 1Gb WAN Infinity port too - so they have followed on the internal design by the looks of it? well that said they have moved from Broadcom to Lantiq, dunno if that means they have to completely change board design?

I think its to do with price, it must be cheaper (pennies) as theres no other logic to it?

be interesting to find out.

[asbokid]

The lack of GbE ports may be down to the power of the CPU, or lack of it.   In the blurb, BT reports that the Lantiq CPU powering the Home Hub 4 is "faster" than the ones in earlier Hub models, but doesn't give any more details.

The CPU is a Lantiq ARX368. It is a 32-bit dual MIPS core System on Chip (SoC), integrating the ethernet switch, DSL front end line driver, and an 802.11n transceiver.

According to the Lantiq Product Brief [1], the second core, probably another MIPS 34Kc core, is called a Protocol Processing Engine. It is dedicated to handling the ethernet switching and the DSP coding and decoding at the DSL driver layer.    Leaving the first core to exclusively run the Linux operating system kernel.

"[T]he XWAYTM ARX300 family is supported by a Protocol Processor Engine which accelerates WAN-LAN-WLAN traffic, and thus guarantees Gigabit routing performance at zero CPU load.

From the same Product Brief, the GbE switch reportedly has 7 ports. 

Maybe switching seven ports at gigabit speeds is just too much for that lil' ol' CPU ?!

cheers, a

[1] http://www.lantiq.com/uploads/media//Lantiq_XWAY-ARX300_Product-Brief_02.pdf

[Black Sheep]

Beat me to it, Asbo. 

[asbokid]

Beat me to it, Asbo. 

 

[kitz]

The lack of GbE ports may be down to the power of the CPU, or lack of it.

Thank you - that is exactly what I thought in my earlier post.  I just didnt have the time to look into or search for any specs at the time, as I had to be elsewhere.

I dont see that it can be financial at all, because the Gb switch is already in there.  10/100 ports are no less expensive than GbE.   
By only having one LAN port they are forcing the EU to attach a separate switch to perform the network switch processing. 

OTOH it is financial because they are cutting back by not putting in a decent CPU...  which is poor because there are several routers on the market that can and do handle Gigabit switching... so if the CPU is a pile of crock, its hardly a 'cutting edge' router is it?

[snadge]

so it's still down to cost because they dont want to afford a better CPU to power all the Gigabit switches  - yup as you say kitz it must be crock if they had too "cut back" on hardware as to allow the CPU to 'cope'..!!

that CPU sounds similar to the BCM6358 in my Netgear DG834N which does the same sort of thing, one core powers the OS and the other the WAN/LAN/WLAN

http://www.linux-mips.org/wiki/Broadcom_SOCs#ADSL_series

[Chrysalis]

The lack of GbE ports may be down to the power of the CPU, or lack of it.   In the blurb, BT reports that the Lantiq CPU powering the Home Hub 4 is "faster" than the ones in earlier Hub models, but doesn't give any more details.

The CPU is a Lantiq ARX368. It is a 32-bit dual MIPS core System on Chip (SoC), integrating the ethernet switch, DSL front end line driver, and an 802.11n transceiver.

According to the Lantiq Product Brief [1], the second core, probably another MIPS 34Kc core, is called a Protocol Processing Engine. It is dedicated to handling the ethernet switching and the DSP coding and decoding at the DSL driver layer.    Leaving the first core to exclusively run the Linux operating system kernel.

"[T]he XWAYTM ARX300 family is supported by a Protocol Processor Engine which accelerates WAN-LAN-WLAN traffic, and thus guarantees Gigabit routing performance at zero CPU load.

From the same Product Brief, the GbE switch reportedly has 7 ports. 

Maybe switching seven ports at gigabit speeds is just too much for that lil' ol' CPU ?!

cheers, a

[1] http://www.lantiq.com/uploads/media//Lantiq_XWAY-ARX300_Product-Brief_02.pdf

possibly but 2 points I wish to make.

generally lan to lan traffic is far less cpu intensive than wan to lan, we know the homehub3 eg. can handle the 330 FTTP product, so it can do 300mbit wan to lan its almost certianly capable of handing gigabit lan data.
The 2nd point is that the hh3 has the same limitation but has a broadcom cpu.

I would be surprised if the hh4 cannot handle 300mbit wan to lan as BT need to make their CPE capable of the products they sell.

[guest]

There are two aspects in play here :

1) Overall router power consumption - last I remember all the major UK (EU?) ISPs had to* sign up to some sort of code for the power usage of such devices;

2) CPU.

Now what I can tell you about an old DG834GT on the old Sky 7dB (conservative) profile and the new 3dB (wtf go for it) profile is :

a) When the line is maxed out on 7dB then DMT Tool still works; maxed out on 3dB then DMT tool will time out. Difference is @ 7dB there's bugger all error correction needed and at 3dB there is;

b) this results in my DG834GT using nearly 20% more power (idle as well) and using one of those laser temp thingies the outside case is 8C warmer on 3dB margin.

So I reckon that until the (Broadcom) SoCs utilise one core for ADSL/VDSL WAN activities and one core for LAN/WAN switching/routing you aren't going to see much in the way of GigE ports.

Oh and the power usage needs to drop to "tick the regulatory box".


*or be castigated as GW deniers/evil/substitute whatever fits