HG612 faster than HH5

I was predicted 11.4-17.2 down (mbps) at order for FTTC. Yes, fairly low but the line length is about 2k. I previously got 7.1 Mbps over ADSL max, but mainly wanted the increased upload. The PCP wires only install happened and the initial speeds were around 9/1 (down/up). I was expecting higher, but was fairly satisfied. But then the upload speed dropped to 0.5 mbps with the upstream SNR going to 15db a few days later.

On recommendation, I purchased a HG612 as my cabinet is Huawei and after hacking it and plugging it all up, I got...11/1.1. I've heard various suggestions about why this is happening from interleaving effects to fortnightly reset of the HH5 causing the MSAN to think fault. But surely this can't be right? The HH5 is BT's flagship home router/modem/gateway? The hack is just to gain access to the interface, it's not an updated firmware.

HH5: IP Profile 8.57mbps
HG612: IP Profile 11.03 mbps. ftp://pedrosmisctech.zapto.org/xdsl.JPG for detailed stats fromt elnet

Once again today, I decided to swap around the modems and the HH5 immediately started connecting at 9mbps max, with about 8 real, whereas the HG612 despite many many reboots by this point was still happy to connect at 14 max, 11 real.

Edited by deleted (Sat 10-Jan-15 22:52:42)

Do you think it's down to differences in the chipset used, one being Broadcom and the other Lantiq?

Broadcom chips are allegedly the best, but BT doesn't want its customer to get too far below the estimate I would think. I had planned to test this on someone who was predicted a solid 80, but gets 65 to see if it helps on shorter lines...but lest I didn't have the time.

Apparently BT are currently implementing PhyR, a Broadcom invention.

Every modem will be slightly different - the complex termination impedance can effect the level of received signal and thus the signal available to the demodulator.

I have both Huawei and ECI modems here and speeds vary by several Mbps. You could get another HH5 and find it syncs faster and another HG612 which syncs slower.

Openreach are also implementing ReTx from this coming Wednesday, it will be rolled out presumably as a firmware update to the cabinets. Might help people with longer lines. Although is PhyR a brand name for retransmission? I guess it probably is.

Edited by deleted (Sun 11-Jan-15 13:12:40)

In reply to a post by Icaras:

Openreach are also implementing ReTx from this coming Wednesday, it will be rolled out presumably as a firmware update to the cabinets. Might help people with longer lines. Although is PhyR a brand name for retransmission? I guess it probably is.

And the relevance to this thread is ... ?

What is ReTx?

In reply to a post by Icaras:

Openreach are also implementing ReTx from this coming Wednesday, it will be rolled out presumably as a firmware update to the cabinets. Might help people with longer lines. Although is PhyR a brand name for retransmission? I guess it probably is.

really?

ReTx is physical retransmission (aka PhyR). I don't know where or how someone here found out that it would be Wednesday, but I'll be keenly watching my local cabinet for G.INP to be enabled on that day. Most probably isn't a firmware update that's needed, but a change of settings on the DSLAM (or profiles on the DSLAM). I presume G.INP will be enabled on all VDSL2 connections by default, this would make sense imo as it's a dynamic form of interleaving/error correction - unlike the current traditional one at the moment.

Anyway, that's all of the off-topic from me.