[Chrysalis]

Originally Posted by TraxData

Yep, comcast are planning 20, 50 and 100mbit symetrical services for sometime late 2009.

I think the 100mbit will fall flat on its arse as their hardware isnt very good.

The rest are very viable though, the 50mbit symetrical is already being trialled (behind closed doors).

Just look at fios, 50/20 package...doesnt that make VM look pathetic?

I been wondering why the uk and usa markets are so different.

In the usa traffic shaping fell flat on its face with congress getting involved and there is clearly more investment going on in their broadband infrastructures (FTTH and DOCSIS3).

In the uk its quite the opposite we have providers falling over themselves trying to get the bottom customers (the ones who want the internet for nothing), there is no real investment going on other than in sales/pr departments and buying customers. Traffic shaping came without a bat from the media until it was already established, traffic shaping is now used by the majority of isps, sky are the only major isp not using it. In addition isps have got away with selling high speed products that in reality are not high speed. Because of this there is no motivation to upgrade the infrastructure to properly support high speed.

So why is this? Could be a few reasons here are some I can think off.

1 - Our consumers are stupid their main concern is price and as long as its cheap enough they fairly satisfied regardless of the impact on quality of service. Example talktalk starts free broadband suddenly people are ringing their current isp for a price match without understanding the economics of it.

2 - Lack of regulation/government/media attention, the ASA already gives isps the green light to call limited services unlimited, they consider a broadband connection that has a fibre backhaul but non fiber local loop to be described as a fibre connection. Both these things alone massively reduce the needs of an isp to upgrade its infrastructure as it now has a licence to missell its product, then we have ofcom who are only interested in a competitive market even if its means the consumer gets screwed. Example again, BT will not invest in FTTH or FTTC because ofcom want them to unbundle it cheaply which effectively makes it unviable to BT, if BT were rolling out FTTC/H then we can be sure VM would be reacting to it.

3 - Related to #2 somewhat our market is way too competitive, prices are too low, 8mbit broadband for £10 has no margins that can fund investment as well as making it no longer possible for light users to subsidise heavier users since there is no longer any profit on light users never mind heavy users, and VM is soon to be going down the same path when they upgrade all 3 of their tiers to faster speeds. It is basically mass selling of bargain basement broadband, quality goes hand in hand with price. Example, adsl prior to 8mbit adsl max was either 20:1 or 50:1 contention ratio and the 50:1 products were actually closer to 30:1, after adsl max launch we no longer see contention ratios defined in products and the reason for this is because now contention ratio is nearer 133:1 for a lot of adsl isps. There is no such thing as something for nothing, the price for increasing adsl speeds at no retail price cost was more people are now sharing the bandwidth. It will be the same on cable when the speeds go up.

4 - governments relationship with media copyright holders, we know they are backing them against the isps threatening to even legislate, so broadband packages with low upload limits make it harder to distribute copyright material.

Thanks to those who can be bothered to read it

---------- Post added at 02:13 ---------- Previous post was at 02:02 ----------

In regards to the turning off analogue.

Virgin was, however, unable to provide details of what will happen in individual areas where it currently provides analogue cable services but not digital. They include parts of Milton Keynes, Westminster, Southampton, Slough and Leicester.

I think VM may well withdraw from some areas especially now they ditched their LLU plans. It seems to make sense as to why they refusing to comment. Clearly they don't/can't upgrade these area to digital. I still remember the phone call I had with a VM exec PA who refused to say they will not withdraw from my area.

---------- Post added at 02:24 ---------- Previous post was at 02:13 ----------

Originally Posted by foddy

That DOES sound a bit simple ... at what layer were you measuring this bandwidth? From 1:46, I'd assume you're just measuring IP packets (40/1500 would be 1.15:46).

But, you probably performed this test over ethernet. On top of your IP packet, you have an ethernet frame plus additional protocol overheads. This would normally add up to 38 bytes (ethernet addresses, packet length, checksum, guard space, etc.)

38 bytes on top of a 1500 byte data packet is 2.5% extra. 38 bytes on top of a 40 byte ack packet is 95% extra, almost double.

So, for ethernet your measured ratio would be 1.95:49.025, assuming everything above; that's close enough to 2:50.

Now, there are two BIG caveats, and one little one.

Firstly, the cable modem is NOT ethernet. I really don't know enough about it to know what sort of overheads there are, but you can be sure there's a source and destination address. The fact that the cable side has MAC addresses which look just like ethernet addresses would suggest that they could be comparable.

Secondly, I've no idea at which protocol level the bandwidth limit is at. If it's discarding the lower-layer protocols before calculating the speed, then 1.33Mbps would be sufficient (although NOT enough to you to make best use of the bandwidth).

If the bandwidth limit INCLUDES the additional overheads (whatever they may be) then it's unlikely that 1.33Mbps would be enough: even 12 bytes (two mac addresses) is enough to increase the bandwidth requirement to 1.77M.

Thirdly, delayed-ack could reduce the ack traffic by half. It will for some people ... but from your calculations above, not you.

Of course, this is all academic if you want to do anything except downloading large files. Most people will be want do to things like check for e-mails, send e-mails, read web pages, have Windows doing updates, NTP updates, weather updates, RSS feeds.

More upload would be beneficial, but then again it's more than you'd get with 20Mbps so it's a move forward.

Yeah delayed ack is a big one, its on by default in windows XP and vista, I turned mine off for some reasons (mainly to decrease tcp latency) and I immediatly noticed my upload bw roughly double during downloading.