Tag: P2P

What kind of core do Kazaa and its supernodes have? Is it iron? Gold? Or is it more of an aluminum core because the cloud that supports the Kazaa P2P network is still malleable — the Supernodes that provide the cloud services are fluid and can change as well as go offline with little or no impact to the system.

I imagine, without going into the architecture of the system, that more than one Supernode is assigned to any particular subnet, others to act as backups, most likely pinging the primary Supernode to see if it’s still in operation. Out of operation, the backup Supernode(s) takes over and a signal is sent to the P2P nodes to get services from this IP address rather than that one. The original Supernode machine may even detect a shutdown and send a signal to the secondaries to take over.

Or perhaps the Supernode IPs are chained and the software on each P2P node checks at this IP first and if no response occurs, automatically goes to the second within the Supernode list and continues on until an active Supernode is found. This would take very little time, and would, for the most part, be transparent to the users.

Again without access to any of the code, and even any architecture documentation (which means there’s some guesswork here) the algorithm behind the Supernode selection list looks for nodes that have the bandwidth, persistent connectivity, and CPU to act as Supernodes with little impact to the computer’s original use. The member nodes of each KaZaA sub-net — call it a circle — would perform searches against the circle’s Supernode, which is, in turn, connected to a group of Supernodes from other circles so that if the information sought in the first circle can’t be found, it will most likely be found in the next Supernode and so on. This is highly scalable.

So far so good — little or no iron in the core, because no one entity, including KaZaA or the owner’s behind KaZaA, can control the existence and termination of the Supernodes. Even though KaZaA is yet another file sharing service rather than a services brokering system, the mechanics would seem to meet our definition of a P2P network. Right?

Wrong.

What happens when a new node wants to enter the KaZaA network? What happens if KaZaA — the corporate body — is forced offline, as it was January 31st because of legal issues? How long will the KaZaA P2P network survive?

In my estimation, a P2P network with no entry point will cease to be a viable entity within 1-2 weeks unless the P2P node owners make a determined effort to keep the network running by designating something to be an entry point. Something with a known IP address. Connectivity to the P2P circle is the primary responsibility of a P2P cloud. KaZaA’s connectivity is based on a hard-coded IP. However, small it is, this is still a kernel of iron.

We need a way for our machines to find not just one but many P2P circles of interest using approaches that have worked effectively for other software services in the past:

We need a way to have these P2P circles learn about each other whenever they accidentally bump up against each other — just as webloggers find each other when their weblogging circles bump up against each other because a member of two circles points out a weblog of interest from one circle to the other.

We need these circle to perform an indelible handshake and exchange of signatures that become part of the makeup of each circle touched so that one entire P2P circle can disappear, but still be recreated because it’s “genetic” makeup is stored in one, two, many other circles. All it would take to restart the original circle is two nodes expressing an interest.

We need a way to propagate the participation information or software or both to support the circles that can persist regardless of whether the original source of said software or information is still operating, just as software viruses have been propagated for years. Ask yourselves this — has the fact that the originator of a virus gone offline impacted on the spread of the said virus? We’ve been harmed by the technology for years, time to use the concepts for good.

We need a way to discover new services using intelligent searches that are communicated to our applications using a standard syntax and meta-language, through the means of a standard communication protocol, collected with intelligent agents, as Google and other search engines have been using for years. What needs to change is to have the agents find the first participating circle on the internet and ask for directions to points of interest from there.

A standard communication protocol, meta-language, syntax. Viral methods of software and information propagation. Circles of interest with their own DNA that can be communicated with other circles when they bump in the night, so to speak. Internet traversing agents that only have to be made slightly smarter — given the ability to ask for directions.

Web of discovery. Doesn’t the thought of all this excite you?

The Don Box discussion about HTTP was a good read with valid points.

From a P2P, not a web services perspective, we need to guarantee certain capabilities in P2P services that we take for granted in more traditional client/server environments. This includes the following:

• Transaction reliability — the old two-phase commit of database technology appears again, but this time in a more challenging guise.
• Transaction auditing — a variation of the two-phase commit, except that auditing is, in some ways, more fo the business aspect of the technology.
• Transaction security — we need to ensure that no one can snoop at the transaction contents, or otherwise violate the transaction playing field.
• Transaction trust — not the same thing as security. Transaction trust means that we have to ensure that the P2P service we’re accessing is the correct one, the valid one, and that the service met some business trust criteria (outside of the technology realm with the latter).
• Service or Peer discovery — still probably one of the more complicated issues about P2P. How do we find services? How do we find P2P circles? How do market our services?
• Peer rediscovery — this is where the iron hits the cloud in all P2P applications I know of. You start a communication with another peer, but that peer goes offline. How do you take up the conversation again without the use of some centralized resource? Same could also be applied to services.
• Bi-directional communication — This is Don’s reference to HTTP’s asymmetric nature. Peers share communication; otherwise you’re only talking about the traditional web services model.

The file transfer nature of Napster or Freenet, and the IM nature of Jabber don’t necessarily consume all of these aspects of P2P applications, so haven’t necessarily pushed the P2P bubble to the max. However, when we start talking about P2P services — a variation of web services one could say — then we know we’re going to be stretching both our technology capabilities, and our trust of the same.

Fun!