Terra Nova Welcomes Jim Purbrick

One of the fortunate few who have been able, at this early stage, to acquire both academic and industry experience in analyzing and implementing virtual worlds, Purbrick hails from Nottingham UK. Primarily a network technologist but also a designer, his credits include experiments with time-linking in virtual worlds (recording and replaying events), persistence mechanisms (the PhD thesis), and real-world projects like Dragon Empires and the now-retired Warhammer Online. In the latter, we would have been treated to Jim's version of a seamless load-balancing technology - a holy grail for us lag-tortured players.

You can see a collection of Jim's writings at this link. Welcome!

Posted by Edward Castronova on August 30, 2004 | Permalink

« Are Virtual Worlds Blind? | Main | Virtual (Wikipediac) Worlds? »

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/t/trackback/5074/1069303

Listed below are links to weblogs that reference Terra Nova Welcomes Jim Purbrick:

» Three-armed boy to have surgery from in Shanghai are
in Shanghai are unsure how best to treat a baby boy born with two left arms. [Read More]

Tracked on Jun 7, 2006 11:07:06 AM

» What's Best For Bedwetting? from treatments. But
most effective way to cure bedwetting, according to a new review of available bedwetting treatments. But researchers say [Read More]

Tracked on Jun 18, 2006 11:59:13 AM

» Indian Muslims Deplore Terrorist Attempt to Attack RSS Headquarter from Tendency to Ascribe
riticizes Tendency to Ascribe Terrorist Act to 'Islam'.... [Read More]

Tracked on Jun 21, 2006 8:46:50 AM

» Bin Laden Hails Slain Zarqawi As 'Lion' from Friday. The 19-minute
shows an old still photo of bin Laden in a split-screen next to images of al-... [Read More]

Tracked on Jun 30, 2006 6:08:35 AM

» GaAs substrate vendors face capacity dilemma from semi-insulating
for RF device applications have to make sure that they don't expand their manufacturing [Read More]

Tracked on Aug 4, 2006 9:16:50 AM

» Brain Stimulation That May Boost Vision From The Corner Of Your Eye from brain function
their colleagues at University College London and appear in the August 8 issue of Current Biology, published by Cell Press. [Read More]

Tracked on Aug 9, 2006 7:34:47 AM

Comments

Betsy Book says:

Welcome Jim! I look forward to reading your comments on Terra Nova.


Posted Aug 30, 2004 10:09:50 AM | link

ren says:

Welcome aboard :)

Posted Aug 30, 2004 11:14:02 AM | link

Dave Rickey says:

Welcome to TN, Jim. If I could ask a technical question that occurred to me reading the paper on MASSIVE-3: When you're resolving a spacially oriented event, is the distance it propagates fixed, or based on the magnitude of the event, the sensitivity of the observer, some combination, or something I can't think of? The paper didn't seem to make it clear.

Also, does MASSIVE-3 have a means for resolving interests that are spacially based? For example, the team in your stadium example, can the agents only communicate via the spacial system, or can they have a direct channel?

--Dave

Posted Aug 30, 2004 5:14:45 PM | link

Dave Rickey says:

Welcome to TN, Jim. If I could ask a technical question that occurred to me reading the paper on MASSIVE-3: When you're resolving a spacially oriented event, is the distance it propagates fixed, or based on the magnitude of the event, the sensitivity of the observer, some combination, or something I can't think of? The paper didn't seem to make it clear.

Also, does MASSIVE-3 have a means for resolving interests that are *not* spacially based? For example, the team in your stadium example, can the agents only communicate via the spacial system, or can they have a direct channel?

--Dave

Posted Aug 30, 2004 5:16:47 PM | link

Cory Ondrejka says:

Welcome, Jim. Absolutely fascinating thesis that I'm looking forward to reading more carefully.

Posted Aug 30, 2004 9:11:23 PM | link

Jim Purbrick says:

Thanks for the warm welcome :-)

Nice to have some questions about MASSIVE-3 too! Events in MASSIVE-3 are propagated to every agent interested in the locale in which the event occurs. There are no restrictions on which locales an agent can be subscribed to. An agent with lots of CPU and bandwidth resources might subscribe to more locales than one running over a dialup connection. Locales don't need to be adjacent either. Entering a CC TV room might subscribe you to a bunch of locales in a distant car park for example. There are a number of general purpose policies in MASSIVE-3, which subscribe agents to the N-nearest locales or which use a cost benefit mechanism to subscribe an agent to a set of locales.

Locales needn't be spatial, so one way to get chat channels or other non-spatial communication mechanisms would be to set up chat locales, but in practice there are a lot of other technologies that can be used for non-spatial communication along side a virtual world infrastructure.

In general agents supply an interest expression which the framework uses to subscribe the agent to publishers. Virtual world literature calls this interest management or awareness management, but it's really just a special case of publisher/subscriber mechanisms.

One potential problem with locales is their granularity: when you subscribe to a locale you learn about everything going on in it. With MASSIVE-3 we added aspects on top of locales, so you could subscribe to certain aspects of a locale. With Warhammer we allowed agents to subscribe to individual items in the world, which gives the granularity you need for dealing with things like invisible characters.

Posted Aug 31, 2004 5:21:00 AM | link