The limitation naturally comes when torrenting / using newsgroups, or when someone is browsing while someone else is gaming etc (small family environment).
I've considered upgrading the router to something with more powerful QoS abilities, but suspect i would struggle to find any router that is able to implement downstream QoS effectively enough to notice the impact; due to the inability to prevent the data coming down the line (i'm sure a half-way house solution would be for it to delay ACK packets and perhaps even drop excess low priority packets to let TCP windowing slow down that particular session – but again, I can't see it being terribly effective as QoS is only really able to handle upstream data with any precision, which is not the problem in this home environment).
So the only realistic option I can see, is to get a second ADSL2+ line installed, and use load balancing or ADSL bonding to do the rest. There does usually seem to be larger additional service costs with bonding over and above those of load balancing, with only one provider I can find that doesn't seem to charge extra for bonding the two lines together (who shall remain nameless for now as I don't want to break any anti-spam policies). And i don't much like the prospect of the 2nd line potentially being a poor one and thereby reducing the speed gains by potentially slowing down the speed of the primary line due to MLPPP limitations - and that's without the fact that it's unlikely to cure latency issues in games nearly as well as load balancing could if i set it up right (In an extreme example: Line 1 (with a low latency gaming focussed provider): Games, Line 2 (with a cheap provider): Everything else).
Obviously whichever way I go, i'm going to need a replacement modem-router (i'm trying to resist having a separate device for the modem and router capabilities because i want a separate wireless access point too). I'm thinking I could keep using the current ISP router as the separate wireless access point to reduce costs, as its performance in the wireless respect has been fine. I'm very conscious that asking for a single device to be a multiple WAN port modem, router and wireless-N access point all in one is likely to be too much for any affordable devices.
I'm not very sure of exactly which routers I should be looking at, even after hours of reading. I hear Draytek aim at this kind of market, but was a little taken aback at finding something of theirs that looked suitable, then finding out it was retailing at £200! (and not much cheaper second hand). However on the other hand i'm very conscious that something underspecced/too cheap will lead to disappointing performance, particularly with 2 lines of ADSL data, expected to be around 32-38Mbps, incoming.
So i'm looking for a dual WAN modem-router on the 'cheaper' side, hopefully commonly available second hand, that will work just fine with 32Megs+ over two ADSL2+ lines, or a brand new but much more future proofed device that I can keep for many years to come to recoup the outlay. I'm leaning towards the former idea over the latter, but would really like to hear about both.
Edit: One thing i should point out, is that i'd be willing to consider replacing all the potential networking hardware with a single PC - i'd have to find something small and discrete and quiet, and then put ADSL2+ PCI cards and wireless and ethernet cards in it too. But i'm concerned about how expensive this may be both to build, and to keep powered up. It would be fairly easy to upgrade it to any future requirements though!
Edited by BloodRazor (Sat 26-Jan-13 19:24:59)