Of Twitter and RSS…
It’s not really a question of life or death. Perhaps it’s time to look for a metaphor that sheds a little more light. The frame that’s been most productive for me is one created by Clayton Christensen and put to work in his book, The Innovator’s Solution.
Specifically, customers—people and companies— have “jobs” that arise regularly and need to get done. When customers become aware of a job that they need to get done in their lives, they look around for a product or service that they can “hire” to get the job done. This is how customers experience life. Their thought processes originate with an awareness of needing to get something done, and then they set out to hire something or someone to do the job as effectively, conveniently and inexpensively as possible. The functional, emotional and social dimensions of the jobs that customers need to get done constitute the circumstances in which they buy. In other words, the jobs that customers are trying to get done or the outcomes that they are trying to achieve constitute a circumstance-based categorization of markets. Companies that target their products at the circumstances in which customers find themselves, rather than at the customers themselves, are those that can launch predictably successful products.
At a very basic level, people are hiring Twitter to do jobs that RSS used to get. The change in usage patterns is probably more akin to getting laid off. Of course, RSS hasn’t been just sitting around. It’s getting job training and has acquired some new skills like RSS Cloud and JSON. This may lead to some new jobs, but it’s unlikely that it’ll get its old job back.
By reviewing some of the issues with RSS, you can find a path to what is making Twitter (and Facebook) successful. While it’s relatively easy to subscribe to a particular RSS feed through an RSS reader— discovery and serendipity are problematic. You only get what you specifically subscribe to. The ping server was a solution to this problem. If, on publication of a new item, a message is sent to a central ping server, an index of new items could be built. This allows discovery to be done on the corpus of feeds to which you don’t subscribe. The highest area of value is in discovering known unknowns, and unknown unknowns. To get to real-time tracking of a high volume of new items as they occur, you need a central index. As Jeff Jonas points out, federated systems are not up to the task:
Whether the data is the query (generated by systems likely at high volumes) or the user invokes a query (by comparison likely lower volumes), there is nodifference. In both cases, this is simply a need for — discoverability — the ability to discover if the enterprise has any related information. If discoverability across a federation of disparate systems is the goal, federated search does not scale, in any practical way, for any amount of money. Period. It is so essential that folks understand this before they run off wasting millions of dollars on fairytale stories backed up by a few math guys with a new vision who have never done it before.
Twitter works as a central index, as a ping server. Because of this, it can provide discovery services on to segments of the Network to which a user is not directly connected. Twitter also operates as a switchboard, it’s capable of opening a real-time messaging channel between any two users in its index. In addition, once a user joins Twitter (or Facebook), the division between publisher and subscriber is dissolved. In RSS, the two roles are distinct. Google also has a central index, once again, here’s Jonas:
Discovery at scale is best solved with some form of central directories or indexes. That is how Google does it (queries hit the Google indexes which return pointers). That is how the DNS works (queries hit a hierarchical set of directories which return pointers). And this is how people locate books at the library (the card catalog is used to reveal pointers to books).
A central index can be built and updated in at least two ways. With Twitter, the participants write directly into the index or send an automated ping to register publication of a new item. Updates are in real time. For Google, the web is like a vast subscription space. Google is like a big RSS reader that polls the web every so often to find out whether there are any new items. They subscribe to everything and then optimize it, so you just have to subscribe to Google.
However, as the speed of publication to the Network increases, the quantity of items sitting in the gap between the times the poll runs continues to grow. A recent TPS Report showed that a record number, 6,939 Tweets Per Second, were published at 4 seconds past midnight on January 1, 2011. If what you’re looking for falls into that gap, you’re out of luck with the polling model. Stock exchanges are another example of a real-time central index. Wall Street has lead the way in developing systems for interpreting streaming data in real time. In high-frequency trading, time is counted in milliseconds and the only way to get an edge is to colocate servers into the same physical space as the exchange.
The exchanges themselves also are profiting from the demand for server space in physical proximity to the markets. Even on the fastest networks, it takes 7 milliseconds for data to travel between the New York markets and Chicago-based servers, and 35 milliseconds between the West and East coasts. Many broker-dealers and execution-services firms are paying premiums to place their servers inside the data centers of Nasdaq and the NYSE.
About 100 firms now colocate their servers with Nasdaq’s, says Brian Hyndman, Nasdaq’s SVP of transaction services, at a going rate of about $3,500 per rack per month. Nasdaq has seen 25 percent annual increases in colocation the past two years, according to Hyndman. Physical colocation eliminates the unavoidable time lags inherent in even the fastest wide area networks. Servers in shared data centers typically are connected via Gigabit Ethernet, with the ultrahigh-speed switching fabric called InfiniBand increasingly used for the same purpose, relates Yaron Haviv, CTO at Voltaire, a supplier of systems that Haviv contends can achieve latencies of less than 1 millionth of a second.
The model of colocation with a real-time central index is one we’ll see more of in a variety of contexts. The relationship between Facebook and Zynga has this general character. StockTwits and Twitter are another example. The real-time central index becomes a platform on which other businesses build a value-added product. We’re now seeing a push to build these kinds of indexes within specific verticals, the enterprise, the military, the government.
The web is not real time. Publishing events on the Network occur in real time, but there is no vantage point from which we can see and handle— in real time— ‘what is new’ on the web. In effect, the only place that real time exists on the web is within these hubs like Twitter and Facebook. The call to create a federated Twitter seems to ignore the laws of physics in favor of the laws of politics.
As we look around the Network, we see a small number of real-time hubs that have established any significant value (liquidity). But as we follow the trend lines radiating from these ideas, it’s clear we’ll see the attempt to create more hubs that produce valuable data streams. Connecting, blending, filtering, mixing and adding to the streams flowing through these hubs is another area that will quickly emerge. And eventually, we’ll see a Network of real-time hubs with a set of complex possibilities for connection. Contracts and treaties between the hubs will form the basis of a new politics and commerce. For those who thought the world wide web marked the end, a final state of the Network, this new landscape will appear alien. But in many ways, that future is already here.