Wednesday Feb 28, 2007

Linux/IPv6 can't talk to itself?

If I remember correctly, USAGI stack should have been intergrated into main-stream Linux kernel since 2.4 era. So IPv6 things should work out-of-box on my 2.6 box, at least basic stuff like TCP or UDP communication over IPv6... But wait, there's big surprise I just found. That is, seems it can't talk to itself through its own IPv6 link-local address, for both TCP and UDP! Using any textbook code snippets - one to send data, and the other to try to receive it. You can see that data just vanish into the void. What's more interesting is that if sending data from another machine to that same address, all data will be received.

My guess is that there's some route issue inside kernel. Linux or USAGI guru out there, any hints?

Saturday Oct 22, 2005

Where is my five rings?

Quoted from Asterisk: The Future of Telephony:
...The most successful key telephone system in the world has a design limitation... when you determine the number of times your phone will ring before it forwards to voicemail, you can choose from 2, 3, 4, 6, or 10 ring cycles. Have you any idea how many times people ask for five rings? Yet the manufacturers absolutely cannot get their heads around the idea that this is a problem. That's the way it works, they say, and users need to get over it.
And another story:
...the name you program on your set can only be seven characters in length. Back in the late 1980s, when this particular system was built, RAM was pretty dear, and storing those seven characters for dozens of sets represented a huge hardware expense. So what's the excuse today? None. Are there any plans to change it? Hardly—the issue is not even officially acknowledged as a problem.
Funny. Comparing to that situation, customers today are a little spoiled \^_\^

Friday Oct 14, 2005

NIS auth and Ubuntu group

Trying to build the whole java workspace on Ubuntu 5.10 now. The first step is to get Ubuntu work smoothly inside SWAN of course. So far everything works fine, e.g. autofs, except one small issue. It seems that a NIS user has limited privileges locally. He can't access audio device, for example. It's quite annoying.

It turns out to be a known issue, though. Check this tip out. It's cool, Guillaume.

Monday Oct 10, 2005

Andy Bechtolsheim on podcast

Check it out:

Monday Feb 28, 2005

Roy Fielding on Apache's 10 year anniversary

Roy Fielding gives his celebration to Apache's 10 year anniversary on apache mailing list.

And, this year is also the 10 anniversaries of Yahoo, Ebay, and Amazon. Netscape had its IPO 10 years ago. All these BIG names of Internet born at the same year. A little surprising, isn't it?

Plus, this year's (well, actually, it's last year) Turing Award is for Vinton G. Cerf and Robert E. Kahn. Can I say this year is the year of Internet, or the year of TCPIP? :-)

Sunday Dec 26, 2004

There's always something interesting

Just read something entertaining, copy it here:
A physicist, an engineer, and a computer scientist were discussing the nature of God. "Surely a physicist," said the physicist, "because early in the Creation, God made light; and you know, Maxwell's equations, the dual nature of electromagnetic waves, the relativistic consequences..." "An Engineer!," said the engineer, "because before making Light, God split the Chaos into Land and Water; it takes a hell of an engineer to handle that big amount of mud, and orderly separation of solids from liquids..." The computer scientist shouted:" And the Chaos, where do you think it was coming from, hmm?"


ps. discovered Sun Net Talk Program. It's a must to visit.

Tuesday Nov 09, 2004


Today read RFC 2396 about URI syntax. I found RFC is subtle, for example:
In general, a character is reserved if the semantics of the URI changes if the character is replaced with its escaped US-ASCII encoding. -- section 2.2
Implementers should be careful not to escape or unescape the same string more than once, since unescaping an already unescaped string might lead to misinterpreting a percent data character as another escaped character, or vice versa in the case of escaping an already escaped string. -- section 2.4.2
These can be real bugs in specific implementation! RFC is RFC. If one get to read it, read it very carefully :-)

Monday Nov 08, 2004


If you cannot read this entry, try making your browser to switch to "UTF-8" encoding.

Anyway, settled down at last. "Life is short. Be assertive". It's time to Tiger, Mustang, and Dolphin.

Sunday Oct 31, 2004

My SunRay story

SunRay is my first machine when I was on board at Sun, you know. I use it and I like it. But until that time I became love it.

Here's the story: I sit in 11th floor of office building. As a new hire, I still have many things to take care of. On day, I think it was some day of last week, I came to Carnegie Hall of 10th floor to do something. I must waited there first. There's nothing to do. So I logged into one SunRay there. Wow! My whole desktop came back and the whole seesion remained the same. It's really amazing! SunRay's vision about mobile desktop is cool.

Hello, blogging world!

This week is my third week at Sun China ERI. I work as a member of Java Security and Networking team. There still have many things to know. But eventually, my work environment here is getting ready.

Actually this is my first try of blogs. Communication is always fun.

So far for the first blog post.



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