What is SoGEA ?

[Jon Schneider]

It is now twenty years since I moved a customer from ISDN to what was
then called "wires only ADSL" and I plugged in an unfamiliar ADSL
router, did minimal configuration and it worked.

I have worked both in DSL chipsets and twisted pair and fibre Ethernet
TAPs but am completely baffled by the way some modern products are
described.

A customer in East Anglia recently got a connection sold as "Superfast
SoGEA 80/20" and I tripped connecting it failing to get any kind of
Ethernet link. (Yes various cables and devices tried.)

I thought the E in SoGEA was for Ethernet and the socket, an RJ45
provided PPPoE which would be fine. But it seems more like it might be
more like PPPoAoVDSL2 in other words not Ethernet at all. Nowhere seems
to describe it.

What _is_ SoGEA as presented at the BT wall socket ?

Jon

[Theo]

SOGEA = single order gigabit ethernet access

That's from the ISP/Openreach's perspective. AIUI, at handover to the ISP
the customer is represented by a single gigabit ethernet link - there is no
phone wiring involved. ISP places a 'single order', Openreach provisions a
gigabit ethernet link to the ISP (I assume it's trunked over
higher-bandwidth fibre links), that's it.

Unlike previous VDSL where you had a DSLAM in a street cabinet but the
copper pair went back to a line card in the exchange for the voice signal,
and provisioning of those two needed to be coordinated, SOGEA is a single
connection - just data, nothing else.

On the customer end it's the same phone pair as before, terminating in an
NTE5 with a BT phone socket on the front. None of this changes. The pair
carries only VDSL, no analogue voice frequencies. The modem decodes VDSL to
PPPoE and the router removes the PPP layer. I think the PPPoE goes back to
the ISP rather than being added by the DSLAM, but I'm not sure.

You can emulate your setup with a separate VDSL modem to get at the PPPoE,
but I'm not sure why you would want to if you can handle that in a router
(of your own choosing, perhaps)

Theo

[MikeS]

Its FTTC without the usual bundled voice services.

[Andy Burns]

Jon Schneider wrote:

> What _is_ SoGEA as presented at the BT wall socket ?

VDSL without any POTS, certainly not ethernet at the point of delivery.

[Andy Burns]

Theo wrote:

> SOGEA = single order gigabit ethernet access

s/gigabit/generic

[Andy Burns]

Jon Schneider wrote:

> it seems more like it might be more like PPPoAoVDSL2

Actually PPPoE (in the UK PPPoA was used on ADSL, but not on VDSL) usual VLAN
tag 101, and you can use RFC4638 baby jumbos, to avoid small MTU problems.

[Theo]

You're right, I'm not sure where I got 'gigabit' from. I doubt there is
actually any 1Gbps cabling on the OR/ISP end - all likely to be aggregated
over 10/25/40/100G fibre, I assume.

Theo

[Gordon Henderson]

In article <j01d2f...@mid.individual.net>,

Jon Schneider <j...@jschneider.tenreversed> wrote:

>What _is_ SoGEA as presented at the BT wall socket ?

A pair of copper wires. It's FTTC DSL without voice. "Dry copper" as
some folks may once have called it. Slightly cheaper although your ISP
may vary.

I have 80/20 SoGEA access via https://1310.io/ There is no voice
although there is a dial tone on the line, but none of the test numbers
do anything, so I have no phone number.

For me, it's plugged into a Vigor 130 modem and that gives me a PPPoE
link to my (Linux based) router.

VDSL2 Information (VDSL2 Firmware Version: 576D17_A/B/C )
Profile State UP Speed Down Speed SNR Upstream SNR Downstream
17A SHOWTIME 19999 (Kbps) 75759 (Kbps) 3 (dB) 3 (dB)

(Hmm.. Down speed is a bit slow this month. Ah well)

Gordon

[Graham J]

Does the term SOGEA only apply to DSL carried on a copper pair?

What about FTTP? Surely the same PPPoA interface is available?

--
Graham J

[Andy Burns]

Graham J wrote:

> Gordon Henderson wrote:
>
>> VDSL2 Information      (VDSL2 Firmware Version:   576D17_A/B/C )
>>    Profile    State        UP Speed    Down Speed    SNR Upstream    SNR
>> Downstream
>>    17A        SHOWTIME    19999 (Kbps)    75759 (Kbps)    3 (dB)        3 (dB)
>>
>> (Hmm.. Down speed is a bit slow this month. Ah well)

Mine's quite content :-)

17A SHOWTIME 19999 (Kbps) 79990 (Kbps) 13 (dB) 3 (dB)

> Does the term SOGEA only apply to DSL carried on a copper pair?

well, they call it SOGFAST for GEA provided over g.fast

> What about FTTP?

not sure they have a name like SOGFTTP though

>  Surely the same PPPoA interface is available?

PPPoE, not PPPoA.

[Graham J]

Andy Burns wrote:

[snip]

>
>> What about FTTP?
>
> not sure they have a name like SOGFTTP though
>
>>   Surely the same PPPoA interface is available?
>
> PPPoE, not PPPoA.

I stand corrected ...


--
Graham J

[Theo]

Graham J <nob...@nowhere.co.uk> wrote:
> Does the term SOGEA only apply to DSL carried on a copper pair?
>
> What about FTTP? Surely the same PPPoA interface is available?

FTTP is described as Openreach's 'Generic Ethernet Access over Fibre to the
Premises', product so GEAFTTP if you like :-)

https://www.openreach.co.uk/cpportal/products/fibre-broadband

I was interested to see there's also 'GEA multicast' over both FTTC and
FTTP, offering an extra multicast VLAN to reduce bandwidth for internet TV.
I wonder which if any ISPs use that?

Theo

[Tweed]

Is there much call for multicast anymore? Once you jump to having your
programmes delivered by Internet most people will start to watching a
programme at a time that suits them. Even if you watch it live, hitting the
pause button destroys any multicast benefit. And, amazingly, it all seems
to work fine right now.

[Andy Burns]

Theo wrote:

> I was interested to see there's also 'GEA multicast' over both FTTC and
> FTTP, offering an extra multicast VLAN to reduce bandwidth for internet TV.
> I wonder which if any ISPs use that?

I think that was a bit of a damp squib, ISTR plusnet tried it for iPlayer, but
it would only apply to watching live channels, not on-demand repeats.

[Theo]

That's what I thought. I think BT Sport used it for their TV offering, and
I suppose for competition reasons Openreach have to offer it as a whitelabel
product to everyone else. (Multicast for IPTV has a long history, back to
various prototypes in the mid 1990s)

What I'm curious about is how they use VLANs at the GEA interface (in
particular, for voice services), but all the technical docs for these
services are behind a login wall.

Theo

[Andy Burns]

Theo wrote:

> What I'm curious about is how they use VLANs at the GEA interface (in
> particular, for voice services), but all the technical docs for these
> services are behind a login wall.

My router can use multiple WAN IP addresses (not just a single external /29
subnet) but they can't each have different VLAN IDs, so I can't think of a way
to reach them even if I knew what they were ...

[Theo]

I assume it's something either underneath or inside the PPPoE layer. Once
it's gone out of the modem it's straight ethernet with no VLANs, but I don't
know what happens at the modem layer.

It could also be that the modem emits both VLAN tagged and untagged frames, and
the tagged frames get filtered off. This is the sort of thing I'm
interested in understanding.

Theo

[grinch]

On 24/11/2021 14:43, Theo wrote:

> Andy Burns <use...@andyburns.uk> wrote:

>>
>> My router can use multiple WAN IP addresses (not just a single external /29
>> subnet) but they can't each have different VLAN IDs, so I can't think of a way
>> to reach them even if I knew what they were ...
>

Vlans are layer 2 where as IP addresses are layer 3. See the seven layer
(ISO) model for more info.

> I assume it's something either underneath or inside the PPPoE layer. Once
> it's gone out of the modem it's straight ethernet

Ethernet is a type of transmission media only its layer 2

Vlans are frames which are sent over Ethernet but still layer 2 IP data
which is layer 3 in encapsulated within the frame

with no VLANs, but I don't
> know what happens at the modem layer.
>
> It could also be that the modem emits both VLAN tagged and untagged frames, and
> the tagged frames get filtered off. This is the sort of thing I'm
> interested in understanding.

VDSL routers in the UK use mostly vlan 101 and only send tagged vlans I
am not sure that for FTTP things are fixed vlan wise it depends on the CP.

It is unlikely that you could use multiple Vlan ID's on FTTP as its a
home user product .You definitely can on Ethernet leased lines I have
done it many times.

Try reading BT/openreach SIN 506 it tells you how FTTP works

>
> Theo
>

[Brian Gregory]

On 23/11/2021 14:59, Gordon Henderson wrote:
> I have 80/20 SoGEA access via https://1310.io/ There is no voice
> although there is a dial tone on the line, but none of the test numbers
> do anything, so I have no phone number.

Why?
The price on their site is more expensive than using a more usual ISP
such as Zen and having a phone connection as well.

--
Brian Gregory (in England).

[Plusnet Support Team]

Any provider that has offered/does offer a Youview service is likely to
deliver some of their subscription content over multicast.

That was certainly the case with Plusnet when they offered TV. All of
the non-Freeview content was delivered using multicast.

--
|Bob Pullen Broadband Solutions for
|Support Home & Business @
|Plusnet Plc. www.plus.net
+--------------- twitter.com/plusnet ----------------

[Chris Green]

Plusnet Support Team <sup...@plus.net> wrote:
> On 24/11/2021 09:58, Theo wrote:
> > Graham J <nob...@nowhere.co.uk> wrote:
> >> Does the term SOGEA only apply to DSL carried on a copper pair?
> >>
> >> What about FTTP? Surely the same PPPoA interface is available?
> >
> > FTTP is described as Openreach's 'Generic Ethernet Access over Fibre to the
> > Premises', product so GEAFTTP if you like :-)
> >
> > https://www.openreach.co.uk/cpportal/products/fibre-broadband
> >
> > I was interested to see there's also 'GEA multicast' over both FTTC and
> > FTTP, offering an extra multicast VLAN to reduce bandwidth for internet TV.
> > I wonder which if any ISPs use that?
>
> Any provider that has offered/does offer a Youview service is likely to
> deliver some of their subscription content over multicast.
>
> That was certainly the case with Plusnet when they offered TV. All of
> the non-Freeview content was delivered using multicast.
>

As I use PlusNet as my ISP does that mean I can turn off multicast in
the settings of my (Draytek) routers now that the BT extras have been
discintinued? Or are there things that still use multicast?

--
Chris Green
·

[Gordon Henderson]

In article <j0a549...@mid.individual.net>,

Brian Gregory <void-invalid...@email.invalid> wrote:
>On 23/11/2021 14:59, Gordon Henderson wrote:
>> I have 80/20 SoGEA access via https://1310.io/ There is no voice
>> although there is a dial tone on the line, but none of the test numbers
>> do anything, so I have no phone number.
>
>Why?

Because I can. It's nice to have the choice.

Gordon

[Brian Gregory]

On 27/11/2021 15:06, Chris Green wrote:
> As I use PlusNet as my ISP does that mean I can turn off multicast in
> the settings of my (Draytek) routers now that the BT extras have been
> discintinued? Or are there things that still use multicast?

It doesn't really matter either way.
Multicast should no longer have any way it can reach your router.