Giga Hub 2.0: PPPoE passthrough/2nd PPPoE session capped (average 330 Mbps) on 3 Gbps plan

[Velaris]

Hello,

I'm on a 3 Gbps plan and I'm seeing a repeatable/hard throughput cap only when using PPPoE on a downstream device (PPPoE passthrough / second session).

My setup:

- Bell Giga Hub 2.0
- Downstream router: UniFi Cloud Gateway Fiber (UCG-Fiber) connected to the Giga Hub 10G port

What works:

- If the UCG-Fiber WAN is set to DHCP (e.g. behind the Giga Hub 2.0/double NAT), I can reach full speed (~3 Gbps).
- If my PC is behind the Giga Hub 2.0 on DHCP, my PC (1GbE NIC) reaches the expected ~1 Gbps.

The problem (reproducible):

When I establish a PPPoE session from a device behind the Giga Hub, throughput is capped around ~300–330 Mbps.

Repro 1: PPPoE from UCG-Fiber

- UCG-Fiber WAN set to PPPoE using my b1 credentials
- Result: ~300–330 Mbps (repeatable), despite 3 Gbps plan

Repro 2: PPPoE from a Windows PC (bypassing UCG-Fiber)

- PC connected by Ethernet to the Giga Hub 2.0
- PC NIC: 1GbE, cable: Cat6A
- Created a Windows "Broadband (PPPoE)" connection using the same b1 credentials
- Result: same cap at ~300–330 Mbps (repeatable)

Because the same cap occurs even when PPPoE is established directly from a PC (*no* UniFi router involved), it points to the Giga Hub 2.0 PPPoE passthrough / secondary PPPoE session path rather than my router.

Can you confirm:

- Is this a known issue on the Giga Hub 2.0 (firmware-related)?
- Is there a firmware update or hardware replacement option to resolve PPPoE passthrough speed caps?

Thanks

[dks]

Thanks for your question. Have you tried using the 5G port as opposed to the 10G port? Bell does not support user installed equipment connected to the Giga Hub. The most recent firmware for the Giga Hub 2.0 is 3.11.3. If you do not have that firmware, rebooting the modem may force an upgrade. Bell does not comment on technical issues, generally. 

If you search "UniFi Cloud Gateway Fiber bell" you will find some useful threads in the Bell sub-reddit which may point you towards your goal. 

[Velaris]

Hello,

I have tried all ports. I am also on 3.11.3.

The issue is not third-party equipment. A PC connected directly to the Giga Hub 2.0 experiences the same speed cap when establishing a PPPoE session via Windows. Unless a user's PC is now considered "user installed equipment".

The Bell subreddit contains conflicting reports, deprecated information and unhelpful suggestions. A direct link to a thread/comment that can help would be appreciated.

Following a technician's visit this morning, it is clear that Bell now speed caps additional PPPoE sessions and prefers to remain ambiguous about this fact. A clear messaging would save a lot of people a lot of time.

[dks]

Thank you for the clarification. There is no reason to initiate or set up a PPPoE session in Windows. It is not necessary. The Giga Hub does all that work. If you have a separate Windows PPPoE session initiated, then you are likely double NATing, which might explain your speed.

Bell forum rules do not permit links to external web pages such as Reddit, so I can't provide you with more information than I have already offered.   

[Velaris]

Thanks for the reply.

> "There is no reason to initiate or set up a PPPoE session in Windows."

The Windows "Broadband (PPPoE)" test is not for everyday use. It's a diagnostic to remove the 3rd-party router from the equation.

Since the same ~330 Mbps cap occurs with PPPoE from both my UniFi gateway and a Windows PC directly connected to the Giga Hub, this points to the Giga Hub 2.0 PPPoE passthrough / additional PPPoE session path and not any specific third-party router.

Establishing PPPoE via Windows does not create double NAT. It receives a public IP and routes traffic over that interface. PPPoE doesn't "create NAT" and that argument is unrelated to the speed cap mentioned.

[dks]

I see you have posted on Reddit. There are good suggestions  and solutions there. I really can’t comment more as your equipment is beyond Bell’s Giga Hub. 

[Velaris]

Respectfully, this isn't "equipment beyond the Giga Hub."

As I stated in my original post and follow-ups, I can reproduce the same speed cap using a Windows PPPoE session from a PC directly connected to the Giga Hub. No third-party router involved.

If you can't comment further, that’s fine - but please stop implying this is caused or relates to third-party equipment, as it unnecessarily muddies the thread.

[Vanadiel]

PPPOE on Unify is hit and miss. My UDM Pro SE has issues with it, so I switched to a Mikrotik to solve those issues.

PPPOE creates a lot of overhead, so often the issue is processing resources.

I would check the CPU load on the home hub when establishing a second PPPOE session, to see if it's being capped out or not. I would also check the PC when using PPPOE, to check the processor usage.

Also check the route when using a PC PPPOE sessions, as it has to be set to 1 in order to avoid issues.

Also, the homehub does not support any form of bypass, so when using a secondary PPPOE session it's not a direct session the way it is with the homehub. session. I would also compare the routing between homehub sessions and PC sessions, to see what the routing is as it might cause an issue if incorrectly set up.

[Velaris]

The UCG Fiber has dedicated PPPoE hardware. Its CPU doesn't break a sweat (tested).

My PC's CPU is capable of handling a PPPoE session (5950X). CPU load is also minimal. The speed cap is identical to the UCG Fiber's, e.g. ~330Mbps down.

As for the Giga Hub 2.0, the load hovered in the 20-40% range during speed tests. Due to the refresh delay, it's hard to get an accurate reading.

I checked the routing and everything looks correct.

When PPPoE is connected, Windows gets a public IP and the preferred route is the PPPoE interface (metric ~26), while the DHCP default route via 192.168.2.1 exists but has a very high metric (~4250). Traffic is definitely going over PPPoE, not leaking to DHCP.

With traceroutes, DHCP starts with 192.168.2.1, PPPoE does *not* (it goes straight into Bell's network).

It doesn't look like a client-side routing issue. The upstream path is very similar once past the home LAN. PPPoE is not taking some wild route.

[Username959]

Seems to be a common issue with 2.0 gigahub. OG giga would get full speed PPOE pass through but would have its own issues, normally latency spikes