Pete Dapkus: /dev/

How to count NATted boxen

Thu, 06 Feb 2003 15:52:30 GMT

An AT&T researcher has presented a paper detailing a technique for counting the number of hosts behind a NAT box (a router that shares a single IP address among multiple machines). Very interesting stuff -- there's a lot of work being done in P2Pland on traversing NATs and allowing machines wiht "private" IP addresses to participate as full-fledged Internet hosts. 644k PDF link Discuss (via /.) [Boing Boing]

Fri, 10 Jan 2003 08:33:13 GMT

Cryptosystems: Debugging IPSec. You've learned about cryptosystems. You understand VPNs. You've installed IPSec. You'd like it to work. Take heart, Dru Lavigne's final installment of "Cryptosystems" explains how to debug IPSec. [O'Reilly Network Articles] someday, I'd like to try to hook up to the VPN in the office using the IPSec impl that is apparently dormant on my mac.

Wed, 13 Nov 2002 19:39:45 GMT
Sony, Philips to buy InterTrust. Companies snag DRM vendor [InfoWorld: Top News] Intertrust gives up on going it on their own after over a decade -- not surprising because since there's no business there. However, the sale price is still pretty high, given the times -- $453mm. No crying for them.

Tue, 12 Nov 2002 06:12:14 GMT
Another Axis customer.
David Watson: I am pleased to report that my migration from Mind Electric Glue to Apache Axis is well under way.
[Sam Ruby]

Wed, 16 Oct 2002 16:09:26 GMT
Java Persistence Frameworks, again.

2002-10-12: Rebelutionary - Re: OFBiz Turning OO on its head?
2002-10-10: James Strachan - Commons SQL
2002-10-10: Jason Carreira - Commons SQL
2002-10-10: BeBlogging - Java Persistence Frameworks
2002-10-10: ::Managability:: - OBiz Turning OO on its head?
2002-09-23: Rebelutionary
2002-09-22: Joe's Jelly: ROI on O/R bridges
2002-07-19: Rebelutionary - Portable CLOBs
2002-07-15: Blogging Roller - Java Persistence Frameworks

... and that is just a few of the recent posts ...

The topic of Java persistence frameworks just keeps on trucking through the Java blogs. I think that the reason the topic keeps coming up is that there is no clear concensus on the "right way" to do persistence. I certainly don't know the right way. But anyway...

I'd like to understand the available tools a little better, so I've started looking at the tools mentioned in the above posts. I found the feature comparison on the Cayenne project's Wiki to be helpful and I also found a very nice set of Java persistence framework development scenarios on the Hibernate website. The Hibernate folks have outlined four development scenerios for using a Java persistence framework: top-down, bottom-up, middle-out, and meet-in-the-middle. Here is my generalized description of these four scenarios, plus a fifth "generic-object" approach that I have added to accomodate OFBiz-EE:

Top-down: Start with an existing JavaBeans object model, develop a mapping that maps those objects to tables in your database, generate DDL to create your database, and then use a persistance API to persist those objects to that database.

Bottom-up: Start with an existing database schema, describe your database schema using using XML or some other meta-data representation, generate your JavaBeans object model, optionally add business logic to those objects, and use a persistence API to store and retrieve your objects.

Middle-out: Start with a meta-data description of your object model, generate your JavaBeans object model, generate DDL to create your dataBase, and use a persistence API to store and retrieve your objects.

Meet-in-the-middle: Start with an existing database schema and an existing JavaBeans object model, develop a mapping to map between the two, and use a persistence API to store and retrieve your objects.Generic-object: Start with a meta-data description of your desired database schema, generate DDL to create your database, and use a persistence API to store and retrieve generic data objects, with values stored as a hash of name-value pairs, to and from your database.

I think the Hibernate guys have really nailed it. Every tool I have seen supports one or more of these scenarios. So I decided to use these scenarios as a way to compare the available Java persistence frameworks. I started to build a table to compare the scenarios supported by the various persistence frameworks and some other factors that I think are important interesting (thanks ceperez): support for the JDO API, support for ODMG API, development activity, and database support.

Here is the first cut of my comparson table, I will be trying to complete it over the next couple of days:

Abra

Castor
JDO
Cayenne Commons
SQL
Hiber
-nate Jakarta
OJB OFBiz
EE Jakarta
Torque
TJDO

Top-down Y
Y
Y
Y
Y
Y
N
N
Y

Bottom-up
Y

Y

N
Y

Middle-out Y
Y
Y
Y
Y

N
Y

Meet-in-middle
Y

Y

N N

Generic-object

Y

JDO API
N
N
N
N
N
soon N
N
Y

ODMG3 API

subset
N
N
Y
Y
N
N

License BSD BSD BSD
APL
LGPL
APL
BSD APL APL

Last release 0.9.6
Sept
2002
0.9.3.21
August
2002
1.0a3
Sept
2002

1.1.4-b
Oct
2002

2.0-b2
July
2002
2.0-b
Sept
2002

SF Activity
19.4% -
98.3%
- 99.9%
- 98.9% - 95.3%

SF Downloads 7
-
2698
-
775
- 86869
- 278

Developers 3

3
3
11
17
11 (1)
10 (2)
7

MySQL Y
Y
Y

Y
Y
Y
Y

PostgreSQL Y
Y

Y
Y
Y
Y

HSQL
Y

Y

Y
Y

Oracle Y
Y
Y

Y
Y
Y
Y

SQL Server
Y

Y

Y
Y

DB2 Y
Y

Y
Y
Y
Y

Sybase
Y
Y
Y

Y

Y
Y

Footnotes:

There are 11 developers on OFBiz, not sure how many really work on the Entity Engine
There are 10 developers on Turbine, not sure how many really work on Torque
Other notes:

I took JGrinder and JRF out of he mix because they seem to be a little too intrusive. They force your to make your persistent objects extend framework objects and they don't seem to offer any tools to help you generate DDL or persistent objects.
I'm going to limit myself to open source frameworks for the time being, but I'd also like to consider Oracle's TopLink, CocoBase, Oracle's BC4J, and the commercial JDO implementations.
I'm also going to ignore EJB CMP for now.
Blank cells still need to be filled in and hints are appreciated
A dash "-" indicates "not applicable.
By the way, Roller uses the bottom-up approach. Roller uses Castor, but not the Castor Source Generator. Instead, Roller uses XDoclet to generate the persistent data objects, Struts form beans, and the Castor Mapping file all from the same source meta-data. The Castor/XDoclet combo is not perfect, but I still don't know that moving to a new framework would be an improvement. We might just be exchanging one set of idiosyncracies for another set. [Blogging Roller]

Film vs Digital

Thu, 26 Sep 2002 02:15:25 GMT
It is often asked if digital cameras meet or exceed the imaging quality of film. Often the discussion about this issue is heated with both sides claiming their point of view is right. Is there a clear answer? In the experiments I've done, using a variety of films and digital sensors, my data and test results show quite a range of answers. [Clarkvision] [Jinn of Quality and Risk]

Olympus sucks.

Thu, 12 Sep 2002 03:40:03 GMT

So, I bought this Olympus Camedia C3020z. Mostly a nice camera. To go with it, I bought a 128MB smartmedia card for around $100.

I formatted the card in my PC using a smartmedia reader after my first use. Despite the fact that it was easy and even natural to do this (I think I was even prompted for it), this was a mistake. Apparently, an unrecoverable one -- according to Olympus, you can never recover the original format of the card once you've formatted on a PC via a reader.   That card works fine, but neither the camera or the bundled software can recover the format required by the camera.

After *much* searching, it appears that if I could write out a nice 128MB FAT12 filesystem (an odd combination to say the least), the camera might be happy again. So far, no luck finding the magic combination of tools, drivers, and operating systems that allows me to do this with my current hardware.

I'm trying to imagine what would make this an acceptable state of affairs for Olympus to subject their customers to this. At the very least, they should have had lots of flashy red warnings on the camera, the manual, and the box they came in.

Tue, 03 Sep 2002 04:21:55 GMT
Disk drives and Moore's law. The bit density of disk drives is doubling every year, which means that it is growing faster than the transistor population of microprocessor chips (which still obeys Moore's law, i.e. doubling every 18 months). By 2010, a single disk drive will hold 50 terabytes, the equivalent of 8000 DVD movies. By that time, PDAs will be more powerful than today's desktop computers. If the duration of copyright protection had remained 14 years (as it originally was) all movies (and TV programmes) made until 1995 would be in the public domain in 2010, i.e. they would be freely viewed and copied. [Jinn of Quality and Risk]
so, the interesting problems then will be: finding enough data to take advantage of your drive -- attention will be the limiting factor...what problems could you solve that you can't solve today if you could just throw diskspace at it (e.g. indexing, tracking all the usage of file, storing every revision); finding a way to organize that doesn't take so much effort (how much time do you spend shuffling files into directories?); finding a way to dive/browse/search an archive of personal data so large you simply could not search it all by hand.

Burn a DVD-AC3 Compatible CD-R

Thu, 29 Aug 2002 07:31:48 GMT
[Slashdot] I'd been trying to find something like this...

blogs amplify

Wed, 21 Aug 2002 16:46:47 GMT

The great thing about a topical community of webloggers is not that it doesn't just filter, it selectively amplifies.    First order, it will pick up and repeat interesting news and ideas -- if you are subscribed to a handful of the blogs in the community, even it's a small subset, you'll likely see everything interesting, and the really interesting things you'll see several times -- because interesting ideas at the shared "frequency" of the community make the network resonate.   Second order, not only do the interesting bits get widely broadcast, they also get refined as they travel -- as add comments or criticism or just add their own riff to the item.

This is not just collaborative filtering. I think Dave Winer calls this "triangulation".   That didn't really make the idea register for me.

Wed, 21 Aug 2002 15:13:23 GMT

I'm a keen advocate of 'less is more' when it comes to web page design. Understated and simple. A bit like me. Thanks are owed to Open Source Web Design for the original template. [Pushing the envelope]

Kool page. Just downloaded a new layout for my weblog.
[Gerhard Froehlich]

Mon, 19 Aug 2002 13:27:30 GMT
Entourage wins again.
I tried to use MailSmith as an Entourage replacement for about an hour this evening. It's very cool, I love the scriptability, the powerful text editing and the lightweight - but I've thrown it away already.

Entourage (despite all it's failings, like the inability to export, to sync with Palm etc) is still the best mail app I've ever used. In case you're wondering, I'm not an M$ sympathiser (I'm using OSX for f'ks sake) but it is good.

Here's why I can't live without Entourage anymore:

Received since launch view - this is awesome. It shows me every mail that I have received since I started Entourage in one place (sorted by date received of course). When everyone filters their mail into a million separate folders, viewing incoming emails is a complete pain in the ass. The inbox is now useless (as it only contains spam) and you need to click around to view new mail. With this view created I can quickly overview all incoming mail as it arrives. Slick. I never knew how much I missed this feature until I didn't have it for an hour.
Flagged mail - I like to click the 'Flag' button and flag mails to return to later. Then I have a view setup to view different types of flagged mails. For example, mail in the Atlassian folder receives greater answering priority that the rebelutionary folder - sorry guys. I thought Labels in MailSmith might do this, but then I still need to click around the folders in the query results window to view mails.
Clickable URLs - Why oh why aren't URLs in MailSmith clickable? Surely this is a basic tenet of any mail program today! (No, command-click doesn't count - it requires two hands)
No HTML mail - Actually, this isn't such a big deal (the text rendered view usually looks ok) but there should be a single button to click to open mail in the browser (it's 3 clicks at the moment by my count).
The "fuck me" interface - As a good designer friend of mine always says, successful applications have "fuck me" graphics. I like the configurability of MailSmith (deeply integrated scripting is very cool) but it's just... boring looking?
[rebelutionary]

Bayesian Spam Filter

Mon, 19 Aug 2002 00:32:38 GMT

An excellent and comprehensive article on filtering spam using Bayesian Statistics by Paul Graham. [Found via 0xdecafbad].
[Bitworking]

Sun, 18 Aug 2002 20:59:27 GMT
An easy way to install Microsoft's TrueType core fonts on Red Hat. [Hack the Planet]

Sat, 17 Aug 2002 00:31:28 GMT

CryptoGram: Palladium and the TCPA. There's been more written about Microsoft's Palladium security initiative than about anything else in computer security in a very long time. My URL list of comments, analysis, and opinions goes on for quite a while. Which is interesting, because we really don't know anything about the details of what it is or how it works. [Tomalak's Realm]

No two ways about it -- Pd is a bad thing. It will transform your PC from the configurable, extensible information tool into an fee-generating instrument for Microsoft, the MPAA, the RIAA, etc.   You won't like it.   This is such a bad idea, if it doesn't collapse under its own weight, it will only because Microsoft propped it up with billions from its cash horde.

Fri, 16 Aug 2002 06:05:25 GMT
Glue kicking ass over Axis....
The Mind Electric has put up some Glue benchmarks. Nothing really unexpected here, but wow. Apache Axis has a lot of catching up to do. Glad to see Glue keeps up with .Net too. As I always say, if you're doing Java SOAP, you should be using Glue.
[rebelutionary]

Danger Device Reviewed

Thu, 15 Aug 2002 06:47:06 GMT
[Slashdot] sounds cool...

Wed, 14 Aug 2002 21:51:08 GMT
David Davies. I missed this earlier. A script that uses Radio's support for Web services to filter RSS feeds for keywords. Very cool. [John Robb's Radio Weblog]

Tue, 13 Aug 2002 18:24:14 GMT
Remember, you can create your own newsfeeds even when they aren't available. Paolo's RSS Distiller (a tool for Radio) is available on eVector's store. This tool essentially gives you the ability to do what Yahoo and the other big news aggegator sites do (given that three years ago these companies spent tens of millions of $$ to do this, the fact that you can run it on your desktop is a hoot). Once you create a feed, you can share it with others using the tool. Nice.   I particularly like the ability to generate feeds from the press release areas on corporate sites. It's perfect for competitive intelligence. [John Robb's Radio Weblog]

web services for travel reservations

Tue, 13 Aug 2002 07:02:31 GMT
Triple A launches Web service airline reservation system. Galileo International takes motoring company from green screen to XML [InfoWorld: Top News]

Fri, 09 Aug 2002 07:01:14 GMT
UI Patterns for the web?. UI Patterns.

UI Patterns and Techniques: Introduction. A set of UI design patterns that shows promise. [ideas]

Looks like a good wrap-up of web ui design patterns. I'll probably go back there and have another go at it when I'm not so busy. ;) (Like, when is that exactly? I have no idea.) [Brett Morgan's Insanity Weblog]

Wow - really good set of UI patterns, but not very web based unfortunately. I would REALLY love to see (and contribute!) to something like this for web UIs. All the standard tricks like master-detail forms, sortable tables, tab interfaces, drill down navigation, form layout etc - but for HTML.
[rebelutionary]

Microsoft, IBM and BEA Deliver Specifications for Business Transactions

Fri, 09 Aug 2002 06:51:50 GMT
. In a late press release tonight, Microsoft, IBM and BEA "announced the publication of specifications to collectively describe how to reliably define, create and connect multiple business processes in a Web services environment, and help organizations coordinate business processes and transactions within the enterprise and with partners and customers across heterogeneous systems and within the enterprise. Announced were the new specifications to address transacted communications of Web services (WS-Coordination, WS-Transaction) and a new language to describe business processes (Business Process Execution Language for Web Services, or BPEL4WS)." [Scott Loftesness]

bar codes generated on-line

Wed, 07 Aug 2002 23:18:01 GMT
"Sighting: Online Barcode Generator " [Daypop Top 40]

Wed, 07 Aug 2002 03:03:37 GMT
Push to Test.

Push To Test. Posted on a jython ml I'm on was something about Push To Test, an open source web service testing framework written in java, with jython as the scripting language for the test-bots. Mike, is this the one you were testing, or another one? [Brett Morgan's Insanity Weblog]

Actually - it wasn't, but it looks cool. I'll check it out more today. I was looking at maxQ and Latka before.
[rebelutionary]

Tue, 06 Aug 2002 03:07:53 GMT
"DeletedDomains.com" [Daypop Top 40]

	Abra	Castor JDO	Cayenne	Commons SQL	Hiber -nate	Jakarta OJB	OFBiz EE	Jakarta Torque	TJDO
Top-down	Y	Y	Y	Y	Y	Y	N	N	Y
Bottom-up		Y			Y		N	Y
Middle-out	Y	Y	Y	Y	Y		N	Y
Meet-in-middle		Y			Y		N	N
Generic-object							Y
JDO API	N	N	N	N	N	soon	N	N	Y
ODMG3 API		subset	N	N	Y	Y	N	N
License	BSD	BSD	BSD	APL	LGPL	APL	BSD	APL	APL
Last release	0.9.6 Sept 2002	0.9.3.21 August 2002	1.0a3 Sept 2002		1.1.4-b Oct 2002		2.0-b2 July 2002		2.0-b Sept 2002
SF Activity	19.4%	-	98.3%	-	99.9%	-	98.9%	-	95.3%
SF Downloads	7	-	2698	-	775	-	86869	-	278
Developers	3		3	3	11	17	11 (1)	10 (2)	7
MySQL	Y	Y	Y		Y	Y	Y	Y
PostgreSQL	Y	Y			Y	Y	Y	Y
HSQL		Y			Y		Y	Y
Oracle	Y	Y	Y		Y	Y	Y	Y
SQL Server		Y			Y		Y	Y
DB2	Y	Y			Y	Y	Y	Y
Sybase	Y	Y	Y		Y		Y	Y