19/05/2005

BBC trials broadband broadcasting - silicon.com

BBC trials broadband broadcasting - silicon.com

Things are moving in the right direction. The Beeb are putting up various TV programmes so they can be downloaded and viewed up to 7 days after they've aired on TV. They've already done this successfully with radio programmes.

They say they're going to use a P2P system, so content is exchanged between users (BitTorrent?) but it will be DRM'ed such that only BBC license fee payers can use it (in the UK you need a license to watch any kind of broadcast TV). The license fees generate about £2.5bn annually for them.

If it all works, it might make PVR's a thing of the past ...

18/05/2005

Skype Supernodes

Imagine a normal broadband user, they've installed Skype on their PC and are happily chatting away. It's likely they're behind a NATted connection. They're probably talking to another user behind a NATted connection. In the IP world this makes life particularly difficult, so how do Skype get around it?

The answer is to use a man-in-the-middle who isn't NATted (I think what Skype call a Supernode).

So if 1st NATted user (a) calls 2nd NATted user (b) all their traffic goes through non-NATted user (c) who has twice the traffic going through their connection. Skype will actually try to put lots of connections through (c).

So if you're on a high bandwidth connection not using NAT and running Skype - you'll probably find it's not just your Skype calls you're handling. The traffic is encrypted, so the you cant actually intercept the voice traffic, but your bandwidth might diminish radipdly.

17/05/2005

Qinetiq to police the airwaves - Network IT Week

Qinetiq to police the airwaves - Network IT Week

It looks like Ofcom are going to get serious about spectrum pollution. They currently have very limited resource in monitoring and then actually doing something about radio interference.

They do go after pirates, but a lot of time is spent investigating industrial EMI that interferes with local services (i.e. say industrial relays arcing that splat over commercial radio).

One thing Ofcom hasn't really addressed is interference in the WiFi bands, either by people using high gain antennae (so putting out more than the allowed EIRP) or using frequencies they're not meant to (or without going through the proper licensing regime), the Quinetiq deal should allow them to police these band much more effectively.

As more of the spectrum is liberalised, it will allow for more flexible use and increased applications, however it will also lead to more people using it improperly.

Maybe this will give Ofcom the bite to police properly, rather than just barking occasionally.

16/05/2005

BT faces fresh competition from AOL in UK fixed-line telecoms mkt - report - Forbes.com

BT faces fresh competition from AOL in UK fixed-line telecoms mkt - report - Forbes.com

AOL are tempting residential away from BT. Unlimited national and local calls for £7.99 pm (these don't tend to include non-geographic numbers like 0844, 0845, 0870 etc, and mobile, premium rate and international numbers which will incur per minute charges).

The business models for flat rate services can work out on average, but copying US models is dangerous since termination charges can largely be avoided there. In Europe termination charges are the norm, which means if users actually make lots of calls or long duration calls - the service could work out unprofitable.

In the UK BT still has the bulk of connections into homes (over 85% of the copper into premises is owned by BT), so they charge other delicious for the priviledge of originating or terminating these calls (i.e. if a AOL subscriber is using AOL's carrier preselect service, when they dial out it has to get from a BT line to AOL and BT charge for that hop, the same for getting a call back to the subscriber). BT still get the line rental, but the CPS provider gets the call traffic.

In order to minimise the number of hops across BT's network you want to connect to as many BT exchanges as possible so hopefully it's only an internal (exchange) hop. However this is generally unfeasable as there are 5,600 digital local exchanges (BT) in the UK. So large providers like THUS, C&W, Energis and possible Carphone Warehouse connect to about 700+ which means that you're never more than 1 hop away.

The "hop" rates are determined by Ofcom (taking a daytime call for termination, BT will charge between about .25p for a local exchange to 1.02p for a "double-tandem long" hop - per minute, origination is about .27p for local exchange to 1.03p per minute). The telco will then put their own margin on top of. In fact they're likely to offer a blended rate, which will average the price to any UK geographic number.

Since AOL have as yet no UK specific telephony infrastructure, it's likely they're buying the service from someone else.

In future they've said they're going to offer a wholesale line rental (WLR) service, whereby they take-over the line from BT and the user no longer gets a BT "blue-bill" at all. However WLR still has issues and isn't that competetive (the operator has to pay BT near enough £10 per month). That may well change with Ofcom pressure.

AOL are also moving into LLU (local loop unbundling) in which case they can offer voice services directly either using traditional means or using VoDSL (which could be VoIP).

It's going to be an interesting time ahead, though voice will soon just be a give-away to complement other services.

Vonage - The Broadband Phone Company

Vonage - The Broadband Phone Company

The Vonage (Linksys) router and phone adapter arrived (it's a combined unit) with an "Internet" Ethernet connection, 3 LAN Ethernet connections and 2 phone sockets. The configuration is quite simple, but you have to be carefull, initially you can only configure the unit from the LAN ports which are set to a 192.168 private address.

Since there was already a DSL router there was no need to configure the Linksys router section (it's a shame they don't bridge between LAN and Internet - there seems no way to do it), which wastes the 3 LAN ports. Once the Internet side had a valid IP address it "just worked".

Plugging in a standard BT phone with CLI display worked too and you could instantly make phone calls (the units are sent out pre-configured to work with your Vonage account). The phone even showed a voicemail indicator when there waiting voicemail at Vonage. Very cute. Unfortunately it wouldn't go away, even when the voicemail was deleted.

After a bit more fiddling and allowing incoming traffic to the unit (through the firewall), the voicemail indicator worked properly too.

Vonage have done an excellent job making the system easy to use and functional.

It's relatively cheap at £9.99 per month for the residential service which includes unlimited UK local and national calls (you do have to pay for non-geographic/mobile and international calls). Calls to other Vonage customers are always free.

Sound quality at the user end seems to be pretty well near toll-grade quality, however other users (on PSTN or Vonage) complained of some echo. That could be because the upstream bandwith of UK ADSL is only 256Kb/s which could be the bottleneck of the call, while downstream is 2Mb/s. Of course most ADSL customers in the UK will be on 512Kb/s downstream and 256Kb/s upstream.

VoIP is starting to make a dent in the regular UK telephony market and the dent is soon going to be a gaping hole. Anyone relying on voice minutes for a business, isn't going to last long. When BT's 21CN comes on-line that will change things forever as the PSTN disappears and everyting is VoIP, but change is already occuring and if BT's promised QoS on DSL does happen, VoIP will rapidly take-over all UK telephony.

Some LLU entrants are already offering VoIP as part of their services (even though the end-user may not be aware of it), it makes sense to do so as it only costs about 40% to build packet networks rather than legacy TDM networks.

The migration to VoIP does introduce interesting challenges, like how to make money? More and more services are being bundled in, and the cost to transport packets from A to B or A to C is pretty well identical, so calls will no longer be charged by destination or even duration. Only time will tell.

D-Link G604T ADSL router

I've been having problems with the router, which turned out to be my fault. The configuration for the firewall and rules is non-intuative.

I had enabled the firewall (which stops things like smurf attacks, SYN flooding etc), but there are some check-boxes to let services in like ftp or telnet. That should have given the game away, in that ALL incoming traffic is blocked unless you specifically let things through (which is a good default). It's not stated anywhere though. Then there's another page called "filters" and this is where you set-up the services you want let through.

Anyway once I'd decided the services to let through, everything worked fine and downloads worked at full-speed.

It seems previously I'd mucked with the rules sufficiently that the router was getting confused and downloads were initially starting very fast, but then crawling to a few K/s.

I still like the D-link router, and hopefully some new firmware will support things like QoS (so I can prioritise my VoIP traffic) and better filter/firewall rules.

Ofcom Website | Powerline Telecoms

Ofcom Website | Powerline Telecoms

Powerline Telecoms, or broadband over powerlines has had relatively poor success in the UK and in Europe in general. It has found a home in places like the Australian outback. Looking at Ofcom's reports you can see why.

In short it looks like using powerlines for backhaul is bad, though there aren't any formal UK (or even EU) specifications the FCC have published emission standards as have the Germans, and the backhaul trials way exceed both of them.

However using broadband over powerlines into homes faired much better, with good results and very low emissions. So as long as the power company can get a decent connection into the electricity substation, it looks like they can safely get broadband into the home.

It wont work in built-up areas (like London) as multiple substations serve premises, so they'd interfere with each other, but then urban areas have probably got DSL or cable. Where it does work is in rural areas where one substation serves lots of premises (well multiple) and they are unlikely to have existing broadband services.