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[sevenlayermuddle]

I'll cross my fingers for you

Thanks, that tactic seems to have worked.  I may ask you do to it again! 

Worth confessing my actual goal in all of this skullduggery is to evaluate the option of moving my modem onto a shelf  near centre of the house where my old ADSL router lived, which is the best place for my wireless AP, and is the place where my central Cat 5 'patch panel' and gigabit switch lives.  That would entail a 7 metre-ish modem patch lead to connect the SSFP to an RJ45 faceplate across the room, then about 8 to 10 metres of existing concealed Cat 5 cabling, then another metre or so patch cable at far end, to modem/router.

I may be making a bold assumption, but I really would not expect that to work at all well with flat untwisted 'modem'  patches.   I'm making no predictions as to whether it will prove satisfactory even with Cat 5 throughout, I suspect it won't, but I'll be interested to try it and see. 

If it proves too detrimental I will abandon the experiment and leave the ECI modem where it is and use ethernet to link the modem to router.

[les-70]

   There is no reason why that should not work.  Your adding about 7+ 9m to your line length which will have a definite small negative impact.  I would recommend using a solid copper cable to BT spec  CW1308 over the whole length.  That should just extend the line.

 If you use CAT 5 it will also work, and quite probably well enough for you to be happy, but the impedance mismatch between the BT drop wire which is CW1308 (CAT 3 i think) and the Cat 5 risks some extra degradation due to reflections at the point of mismatch. If any of the run will be Cat 5 then it would be best to be all Cat 5.   The amount of degradation could be calculated but I would not like to do the sums.

[loonylion]

leave the ECI modem where it is and use ethernet to link the modem to router.

This is how I would do it.

[roseway]

The SSFP has unfiltered A/B terminals on its front side, so the most straightforward solution would be to wire up an unfiltered extension using CW1308 (or Cat5) from these A/B terminals to a socket near where you want to put the modem. This would minimise the number of plug/socket interfaces in the link.

[sevenlayermuddle]

I will also be trying my old DSL1 configuration, which is to remove the SSFP, disconnect ring wire, and allow the DSL signal to travel with the telephone extension wiring to an extension socket near the router.  That socket is equipped with an ADSLNation filtered faceplate, thus isolating the remainder of the extension wiring from DSL.   Electrically, I have always argued, disregarding the slight percentile  increase in line length, that is pretty much equivalent to connecting directly to a master socket with SSFP.   It remains to be seen however whether the ADSLNation filter works as well with VDSL.

My own money/hunch is on the Cat 5 solution doing better by benefiting from increased twist spec, and the fact I have no confidence that the extension wiring (installed by builder) really meets BT's specs.   But we shall see.   For sure you could argue that any 'damage' done by CW1308 will already have been done by the 550  metres between cabinet and home, and another 20m or so is irrelevant.

That said, another downside of the Cat 5 solution will include the fact that the SSFP internal filter (it is a mk3) will be some distance upstream from it's ideal location close to modem, as recently discussed in other threads.

leave the ECI modem where it is and use ethernet to link the modem to router.

This is how I would do it.

Me too but, if I want to get line stats from a bridge-mode modem I'll need a second LAN.   And unfortunately owing to my cabling layout, only one was going spare in that room, all others are spoken for.  It would be nice to avoid needing another switch, just on principle.

[sevenlayermuddle]

The SSFP has unfiltered A/B terminals on its front side, so the most straightforward solution would be to wire up an unfiltered extension using CW1308 (or Cat5) from these A/B terminals to a socket near where you want to put the modem. This would minimise the number of plug/socket interfaces in the link.

Agreed that might work well.   But some years ago I took the trouble of installing concealed Cat 5 wiring everywhere with neat surface mounted RJ45 faceplates in all rooms.   I really don't want to start tearing out holes in the walls again, and it would be a big admission of defeat to end up with wires tacked to the skirting boards through two rooms after all that effort. 

[loonylion]

leave the ECI modem where it is and use ethernet to link the modem to router.

This is how I would do it.

Me too but, if I want to get line stats from a bridge-mode modem I'll need a second LAN.   And unfortunately owing to my cabling layout, only one was going spare in that room, all others are spoken for.  It would be nice to avoid needing another switch, just on principle.

There's another option but its a bit of a hack. Cat-5e has 4 pairs, only two of which are actually needed for 100mbps. You can actually buy/build splitters that will run one LAN port on 2 pairs and another LAN port on the other 2 pairs, thereby only using one structured cable run for two LAN ports. So you have a splitter at each end of the run (one in the wall jack, one in the patch panel).

[sevenlayermuddle]

There's another option but its a bit of a hack. Cat-5e has 4 pairs, only two of which are actually needed for 100mbps. You can actually buy/build splitters that will run one LAN port on 2 pairs and another LAN port on the other 2 pairs, thereby only using one structured cable run for two LAN ports. So you have a splitter at each end of the run (one in the wall jack, one in the patch panel).

Actually, that is an interesting idea, very few things really need gigabit speeds.    Thanks, I'll add it to my growing list of options. 

Even so, I can't resist putting on my pedant's hat and pointing out that it should not need Cat 5e, as Cat 5 also has four pairs.  Thanks again, though. 

[sevenlayermuddle]

The postman just bought me a bag of RJ11 plugs, and I have spent a happy half hour playing with my rarely used crimp tool, making up patch cables.   Result of effectively extending the modem patch cable to circa 20 metres in three sections of identical Cat 5...? 

A small but measurable drop in downstream speed test, from circa 46-ish to 42-ish.    Sounds like that idea's dead in the water then. 

Purely for interests' sakes, I now look forwards to directly comparing the Belkin screened Cat 5 patch with an unscreened one I have made myself, of similar length, with modem back at the SSFP.  But as noted by Eric I must tread carefully so as not to upset DLM.  The excitement of that experiment will have to wait until tomorrow.   

[Dray]

You might try one length of solid copper cat5 instead of three stranded patch cables

[sevenlayermuddle]

You might try one length of solid copper cat5 instead of three stranded patch cables

Thanks, but check out reply #35 

Purely for interests' sakes, I now look forwards to directly comparing the Belkin screened Cat 5 patch with an unscreened one I have made myself, of similar length, with modem back at the SSFP.

Impatience got the better of me   

I have now replaced the modem close the the SSFP and tried a side-by-side comparison of similar (normal) length screened and unscreened modem cables.  The unscreened one was made DIY, but has all four pins connected for fair comparison with the Belkin.

It transpires that the Belkin screened (ungrounded) Cat 5 patch gave similar results as posted earlier in thread and is distinctly inferior to an otherwise similar unscreened Cat 5 cable.  The unscreened Cat 5 is pretty much as good, but no better than, the untwisted freebie that came with the install.

I really will wait til tomorrow before trying the CW1308 options.  At least, I'll try to wait.....

[Dray]

I'm not sure screened patch cable would be any different to unscreened, it's the twisting that gives the noise rejection. Solid copper works better than stranded for analog transmission.

[sevenlayermuddle]

As update to all this, I have decided to adopt the obviously better solution of leaving modem by the master socket, with ethernet over the Cat 5 link to the router.  It means I can't use a combined modem/router but that doesn't really worry me, and the modem can't be eating much power as it runs stone cold.

As well as being technically more elegant, I also like the idea that the installation is exactly as left by the installing engineer.   Deviating from that situation, whilst legal, might lead to arguments if any line faults were to need investigated by OR or their subcontractors.

The compromise is that I can't get modem stats with that single cable.   That could be addressed using Loonylion's suggestion of cable splitters.   But in any case I have discovered I already have access to the most interesting stat of all, connection sync rate history, without even unlocking the modem... it's available for viewing in Zen's customer portal!

[les-70]

   You could used a combined modem router but as only one port would be used you most likely need the second router.  With a combined device you would get access to the modem and stats over the single Ethernet cable.

[sevenlayermuddle]

I'm far more awkward than that.

I want the wireless AP to be at the centre of the house for best coverage, whereas the master socket is on an outside wall.  So yes, I could go for a combined modem/router, but then I'd want a separate AP and nothing really gained.

Also, the router supplements an 8 port switch in its current location, I'd be short of ports at that location if the router were moved and want a bigger switch to make up for it, so it's getting expensive!