Communications

3G's biggest success is as a dumb pipe

Thanks to Dean Bubley for pointing out this presentation by Antero Kivi on the use of 3G mobile networks in Finland.

92% of all data traffic is from PCs

Furthermore, of the 4% of traffic from Symbian devices, 79% of that is for web access and 10% is for email.  So users are paying for mobile data for the sole purpose of connecting to the Internet.

Put another way, mobile operators have failed to provide any operator-specific data application of any relevance.

Why invest another penny in IMS?

Voice telephony needs priority, but after that all people want is a dumb pipe. In a competitive market that what they'll get. So IMS is vastly more complex than appropriate.

The cost effective solution is simple (i.e. two) priorities on the radio link, softswitch-controlled circuits-over-packets for voice telephony and straight off-load to the public Internet for everything else. An IP/MPLS core network is more than sufficient.  And existing GSM voice telephony protocols are both adequate and appropriate for voice telephony.  Existing GSM signaling is already being carried over Sigtran over IP, so the pieces are falling in place.

What I've just described matches what I've seen of China Mobile's new 3G backbone.  If true, that means the Chinese network equipment providers (Huawei, ZTE, etc.) are well positioned to win 3G business in high growth emerging markets where costs are key.

It certainly sounds bad for IMS.

NGN ≠ the Internet, and never will

I see and hear a lot of confusion about next generation networks (NGN).  In most cases people are using the term roughly as the ITU-T defines it:

A Next Generation Network (NGN) is a packet-based network able to provide services including Telecommunication Services and able to make use of multiple broadband, QoS-enabled transport technologies and in which service-related functions are independent from underlying transport-related technologies.

but many people don't realize how little this has to do with the Internet.

The Internet is a "network of networks" that includes millions of smaller domestic, academic, business, and government networks interconnected using IP.  It is a hierarchy because there is a backbone of ~28,000 autonomous systems (ASs) which exchange IP packets using routes established by Border Gateway Protocol (BGP).  The remaining millions of networks connect to that backbone via hundreds of thousands of ISPs and other intermediaries who are ASs or connect to an AS.

All of the NGN proposals (Wikipedia has a good summary) involve sophisticated QoS.  But it is well established that there is no technical or commercial requirement for QoS on the Internet backbone (references discussed here and here).

The thousands of organizations that are ASs exist in hundreds of different jurisdictions.  While some ASs are heavily controlled by governments (there is basically one AS for all of China), AS interconnection is independent of any single government.  Interconnections occur based on tradeoffs between the cost of doing business locally and the cost of routes to other locations.

Indeed, to the extent Tier 1 ISPs have attempted to limit free peering, Tier 2 ISPs have established peering agreements that form a donut around the Tier 1s, thus cutting Tier 2s' transit costs to an absolute minimum.  So the effectively unregulated Internet backbone is working remarkably well based on commercial arrangements between thousands of parties, just as it has for 15+ years.

With no technical need for QoS on backbone routes (as discussed here) and no commercial reason that anyone has articulated, it's hard to see how the thousands of parties who make up the core of the Internet would agree to do anything with QoS, ever.

Established telephone companies will deploy NGNs for telephone service.  To the extent they have a monopoly on Internet access, they will be able to use their NGNs to block access to the Internet, but the existence of NGNs won't change the way the Internet core works or the way anyone else's network works.

So NGN's are an evolution path for existing telephony networks, not the Internet, and they will last as long as the existing telephone service model lasts and no longer.

Why there is no Internet QoS

In 2006, I wrote a short blog post on why there is no Internet QoS and likely never will be.  That post is a continuing source click throughs and email inquiries so, when Jon Arnold asked me to write a guest article for IP Convergence TV, I thought I'd tackle the definitive story on Internet QoS.

Here is the new article: Why there is no Internet QoS.  It may or may not be definitive, but I have filled in the engineering and economic background, and I investigate where QoS has been deployed in networks in order to identify where there may be QoS related opportunities for ISPs.

My conclusions:

• There is no Internet QoS today, and it’s unlikely any complex QoS scheme will ever be added to the Internet as a whole.
  
• To the extent next generation networks with rich QoS are deployed, this will only happen within walled gardens, not as part of the public Internet.
  
• But there may be opportunities for ISPs to create a simple premium service that could generate incremental revenue.

Tracing Internet connections by inter-packet timing correlation

Susan Crawford's post The Auction, the Cops, and Comcast, highlights a request from the US Department of Justice to the FCC that is likely to result in an FCC Notice of Proposed Rule Making (NPRM).  As I read her post, I recalled an interesting paper on surveillance.  Here's the relevant part of Susan's post (bold italic highlighting is mine):

The NPRM, if it follows the DOJ’s request, will suggest (among other things) that all of these providers should build their routers and network hardware to provide “packet activity reporting” for all packets crossing their networks, and physical location information for all of their customers at all times. It will also suggest that very fine-grained timing information is needed - something that the internet and its applications don’t provide at the moment. “Packet activity reporting” means that the broadband provider will need to know the destination IP address and port number for everything happening on its network.

The idea is that these designs will help law enforcement when they want to carry out a request for call-identifying information.

A few months ago I happen to read a 2002 paper by Xinyuan Wang, Douglas S. Reeves and S. Felix Wu entitled Inter-Packet Delay Based Correlation for Tracing Encrypted Connections Through Stepping Stones.

I should comment that, when I travel in China, I use TOR (The Onion Router)
to bypass the Great China Firewall.  TOR works by passing your traffic through a series of intermediate routers, with intermediate connections encrypted, so a third party observer can't tell whose traffic is going where.  This is mildly useful to me when I'm in China, but it can be life saving for dissident writers living in totalitarian states. 

So it was somewhat distressing when I read the paper by Wang et al.

From their abstract:

... we address the problem of tracing encrypted connections through stepping stones. The incoming and outgoing connections through a stepping stone must be correlated to accomplish this. We propose a novel correlation scheme based on inter-packet timing characteristics of both encrypted and unencrypted connections. We show that (after some filtering) inter-packet delays (IPDs) of both encrypted and unencrypted, interactive connections are preserved across many router hops and stepping stones.

and from their conclusion:

Our correlation metric does not require clock synchronization, and allows correlation of measurements taken at widely scattered points. Our method also requires only small packet sequences (on the order of a few dozen packets) for correlation. We have found that after some filtering, IPDs (Inter-Packet Delay) of both encrypted and unencrypted, interactive connections are largely preserved across many hops stepping-stones. We have demonstrated that both encrypted and unencrypted, interactive connections can be effectively correlated and differentiated based on IPD characteristics.

So it's clear what the Department of Justice has in mind.  Of course, if the Department of Justice gets this through, it will just be an added expense on all ISPs (and thus on their customers, i.e. you and me).  It won't actually work against the bad guys (or the good guys) as it's fairly simple to imagine an outbound packet scheduler that introduces jitter into each flow at each onion router.

Singapore's Next Generation National Broadband Network

My post on Tuesday was in response to a Singapore government press release that used the phrases "structural separation" and "passive network." 

Subsequently I've been pointed to this website where the Singapore government has posted the qualification documents, mainly document IDA(PQ)-010V2, dated 11 December 2007.  It appears the actual RFP is only available to qualified bidders, but the qualification document has good information on the project structure.

Here is their view of structural separation:

Here is the supporting text:

3.3.2  There will be three distinct types of functional entities operating on the NGNBN.  At the lowest layer, the NetCo would be responsible for the design, build and operation of the NGNBN's passive infrastructure, which includes ducts and wirelines.  The NetCo would offer this passive infrastructure at a wholesale, non-discriminatory and cost-competitive basis (Layer 1 Open Access) to the OpCo(s).  The NetCo's passive infrastructure would be rolled out extensively throughout Singapore.  The NetCo infrastructure is expected to be capital-intensive with massive implementation effort.

To me that implies multiple OpCos can get access to dark fiber.  Hopefully private companies, who want their own dark fiber from one building to another, would also be able to lease dark fiber.  However, they don't make this clear so we'll have to wait and see. 

Only the NetCo portion is covered by the current RFP.  The Singapore government expects the NetCo piece to be built and operated by a private company or consortium, and they are prepared to provide up to S$750M (US$521M) in grants to make this happen.  Responses are due 25 March 2008 and will be evaluated based on:

• Attractiveness of business plan to industry
• Quality of network infrastructure
• Level of Government grant
• Financial proposition and strength of bidder

This is one to watch!

Rate of growth of traffic at the Amsterdam Internet Exchange

Here's a great historical graph, from page 28 here, showing the growth in traffic at the Amsterdam Internet Exchange.

By my take off from this graph, there was 1000x growth in nine years.  That means traffic doubles every 11 months.  While this is only one data point, it's new to me and fairly up-to-date.  It's also roughly consistent with the 12 month doubling rate mentioned in my earlier post.

Managed Storage Futures

Recently I wrote about differences in the exponential growth rates of computing and networking and promised to say more about how these differences cause substantial shifts in the technology landscape.  Managed storage is one example.  The relevant doubling rates (from that earlier post) are:

Doubling Rates

Technology Measure	Months
Computing performance	18
Storage capacity	12
Networking performance	15
Access connectivity	20-26

The increase in storage capacity per dollar has been phenomenal and is one of the reasons that Google can offer Gbytes of free storage for email and that Amazon can offer their Simple Storage Service (Amazon S3) at extremely low rates.

But it's also caused headaches for IT directors, as installed equipment becomes obsolete long before it's fully depreciated, and employees and department heads grip about inflated internal billing rates for storage.  Pity the IT staffer who sends a broadcast message justifying corporate email storage limits because "it costs the company X cents per megabyte per month."  I've seen such messages, and the employee ridicule they engender.

This sounds like a perfect opportunity for a managed service — provide an interface that looks a storage area network or network attached storage, using multiple (for reliability and arbitrage) Internet-based storage services to provide the actual storage.  But now differential growth rates become a factor.

Storage costs decline a bit more rapidly than the cost of Internet transit.  So, already it's the case that network-based storage is extremely low cost for backup but less affordable for transactions.

But the real problem is the cost of access connectivity.  If you're selling managed services to IT departments, you need to provide services at their premises.  Local connectivity is not fast, cheap or reliable, and the pace at which it improves is glacial in comparison with storage or Internet transit.

Has this prevented the emergence of managed storage solutions?  Of course not.  But most existing solutions focus on remotely managing equipment that's physically on the enterprise premises.

Is there opportunity for network-based managed services.  Also, yes.  But you will need considerable focus on local connectivity, both for the numbers you use in your business plan and for the specifics of how you implement the service.  Some thoughts:  interface your managed service via a remotely managed on-premise box that includes caching?  use a dedicated access link to guarantee QoS?  ???

In any event, three years from now, you can count of disk storage being ~8X more affordable, Internet transit being perhaps 4x more affordable, but local connectivity only 2x or 2.5x.  Don't give up your great  business idea, but plan accordingly.

Communications' Exponential Growth Rates

Everyone in high tech is familiar with Moore's Law and most are aware that similar exponential growth occurs in many other measures of digital technology, for example disk storage.  What about communications?

Gordon Moore referred to the number of transistors that could be inexpensively placed on an integrated circuit.  The Wikipedia entry for Moore's Law mentions other measures that are increasing at exponential rates as alternate "formulations" of Moore's Law, e.g., computing power, hard disk capacity and pixels per dollar.  Unfortunately, Wikipedia (at least so far) doesn't have accurate doubling rates or supporting data for these other measures and they present little on the area that most interests me -— communications.

Why care?  Different rates of exponential growth can cause substantial shifts in the technology landscape, some of which I'll discuss in subsequent posts.

Here are the doubling rates for some measures I'm interested in:

Note 1:  Density at minimum cost per transistor, see the Wikipedia article on Moore's Law.

Note 2:  12-24 months depending on how computation is being measured.  See, for example, the arguments here.

Note 3:  Since the mid-1990s, disk capacity has doubled  every 12 months.  In earlier decades, it was more like 15 months (based on calculations from this data), but since 1995 (through today) the 12 month rule has held.

Note 4:  Based on these data points:

Note 5:  The classic reference is Odlyzko & Coffman (2001) (also 1998).

Note 6:  My personal Internet connectivity is documented here (for data to me).  For data rates from me to the Internet, the Feb 2007 value is 2.7 Mbps, which implies a 26 month doubling period (versus 20 months for data rates to me).

Off to Madrid for Connect 2007 Europe

The third and final Connect conference of 2007 is taking place in Madrid on Wednesday and Thursday, November 7th and 8th and I'll be there.  My blog comments on earlier conferences are here (& 1, 2, 3, 4, 5, 6, 7, 8).

Day One has a heavy focus on mobile industry issues and mobile applications. And, it's conducted as panel discussions with few or no slides.  Perhaps this only works because there are good speakers, chosen to promote controversy and discussion, but it really works!  In both 2006 and so far in 2007, the nature of the discussion has been much, much better than at a typical industry show.  The session descriptions for November 7th are here and the speaker bios are here.  If you can be in Madrid on Wednesday, you should attend.

Day Two is a more traditional developers conference focusing on NMS technology and products that are used to create many of the applications discussed by the Day One executives.  Check out the Day Two program.

The day the routers died (to music)

The RIPE 55 meeting in Amsterdam has ended and Raindeer just uploaded this summary to his blog Lunatic Thought:

"The RIPE 55 meeting has just concluded. There was much debate on what to do on the imminent depletion of the unallocated IPv4 pool in 2010. We could do nothing or we could create a market place and facilitate transfer of IP-adresses, but it's all a train wreck waiting to happen. This is best shown however by a beautiful song "The day the routers died" also available on Youtube written and performed by Gary Feldman. So please all upgrade to IPv6 soon, or else you will not get 40Gbit/s to your mother."

and points to this wonderfully funny video: