With IPv6, everything from appliances to automobiles can be interconnected. But an increased number of IT addresses isn’t the only advantage of IPv6 over IPv4. In honor of World IPv6 Day, here are six more good reasons to make sure your hardware, software, and services support IPv6.

1. More Efficient Routing
   IPv6 reduces the size of routing tables and makes routing more efficient and hierarchical. IPv6 allows ISPs to aggregate the prefixes of their customers’ networks into a single prefix and announce this one prefix to the IPv6 Internet. In addition, in IPv6 networks, fragmentation is handled by the source device, rather than the router, using a protocol for discovery of the path’s maximum transmission unit (MTU).
2. More Efficient Packet Processing
   IPv6′s simplified packet header makes packet processing more efficient. Compared with IPv4, IPv6 contains no IP-level checksum, so the checksum does not need to be recalculated at every router hop. Getting rid of the IP-level checksum was possible because most link-layer technologies already contain checksum and error-control capabilities. In addition, most transport layers, which handle end-to-end connectivity, have a checksum that enables error detection.
3. Directed Data Flows
   IPv6 supports multicast rather than broadcast. Multicast allows bandwidth-intensive packet flows (like multimedia streams) to be sent to multiple destinations simultaneously, saving network bandwidth. Disinterested hosts no longer must process broadcast packets. In addition, the IPv6 header has a new field, named Flow Label, that can identify packets belonging to the same flow.
4. Simplified Network Configuration
   Address auto-configuration (address assignment) is built in to IPv6. A router will send the prefix of the local link in its router advertisements. A host can generate its own IP address by appending its link-layer (MAC) address, converted into Extended Universal Identifier (EUI) 64-bit format, to the 64 bits of the local link prefix.
5. Support For New Services
   By eliminating Network Address Translation (NAT), true end-to-end connectivity at the IP layer is restored, enabling new and valuable services. Peer-to-peer networks are easier to create and maintain, and services such as VoIP and Quality of Service (QoS) become more robust.
6. Security
   IPSec, which provides confidentiality, authentication and data integrity, is baked into in IPv6. Because of their potential to carry malware, IPv4 ICMP packets are often blocked by corporate firewalls, but ICMPv6, the implementation of the Internet Control Message Protocol for IPv6, may be permitted because IPSec can be applied to the ICMPv6 packets.

Source: http://www.networkcomputing.com/ipv6/230500009?cid=NWC_report_2011-06-09_html

Like most other browsers, Google Chrome has some special pages that show information about memory usage, cached files, plug-ins and more. Here’s a list of the most interesting about: pages available in Google Chrome (you can open them by dragging about:name to the address bar).
1. about:version – Google Chrome shows the version number the browser, WebKit and V8 (JavaScript engine). You can also find the user-agent used by Google Chrome:

Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/525.19 (KHTML, like Gecko) Version/3.1 Safari/525.19

2. about:plugins – the list of plug-ins that are available in Google Chrome: Shockwave Flash, RealPlayer etc.

3. about:cache – a list of all the web pages cached by Google Chrome. The browser doesn’t have an option to limit the cache’s size, so it’s recommended to regularly empty the cache.

4. about:memory – this pages compares the memory used by all the active browsers and by Google Chrome’s tabs.

5. about:stats – a list of internal counters and timers that has a funny subtitle “Shhh! This page is secret!”.

6. about:histograms – a list of histograms for Google Chrome’s internal metrics.

7. about:dns – Google Chrome prefetches the DNS records for 10 frequently visited hostnames. This feature can be disabled in Options > Under the Hood by unchecking “Use DNS pre-fetching to improve page load performance”.

8. about:network – this page could be used for I/O tracking and it’s a partial replacement for the Live HTTP Headers extension. Click on “Start I/O tracking”, open a web page in a new tab and you’ll get a list of all the images, scripts and objects loaded from that web page.

9. about:crash – crash the active tab. Google Chrome displays the “sad tab” image, followed by this message: “Something went wrong while displaying this webpage. To continue, press Reload or go to another page”.

10. about:hang – type this in the address bar of a tab when there’s already an active web page to hang the process (this means that the process no longer accepts any signal, but it’s still running). The other tabs will continue to work and the active tab can be closed.

11. about:internets – this is an Easter egg that references two popular Internet memes: Internets and Series of tubes.

In one of our screencasts – How to Install a Self Signed Certificate in IIS6 we have demonstrated the use of the SelfSSL.exe tool from IIS6 resource kit.

We get a lot of questions about creating a Self-Signed Certificate in Windows Server 2008. There is an option in IIS7 Manager to create a self-signed certificate, and this is an easy, and straightforward way to generate a certificate yourself. The problem with this approach is that you can not specify the name of the web site, because when you generate the certificate – IIS7 Manager uses the default FQDN of the server. In most cases, the FQDN by which the server is accessed, is different from the real name of the server.

We get a lot of questions, whether you can use SelfSSL.exe and generate a Self-Signed Certificate in IIS7. In step3, we demonstrate how to use SelfSSL.exe to generate and assign a certificate, using the correct name of the web site. In addition we import it, and add the issuer to the root of the trusted certificate authorities, so you do not get a warning every time you open the web site.

References: http://www.netometer.com/video/tutorials/server-2008-self-signed-certtificate/index.php

一隻好有意思既歌

於心有愧

歌手：陳奕迅
作曲：鍾達茵
填詞：林夕
編曲：唐奕聰

如果我聽歌可眼紅 何以待你好偏不懂
自細做過多少美夢 慈悲的偉論
連乞丐喊窮心也痛
竟怕放懷擁抱你 讓你露歡容
追悔無用 轉眼發現 你失蹤

曾聽說過 你某夜結婚 未曾露笑容
實在不敢知道我是元兇

大概當初我未懂得顧忌
年少率性害慘你
令人受傷滋味 難保更可悲
這心地 再善良終生怎去 向你說對不起

良心有愧 原來隨便錯手
可毀了人一世
立志助世人脫貧以為
便偉大到像多麼有為
這種剌蝟 連誰曾待我好
都可帶來傷勢
被我害過來接受我跪
是我在製造眼淚居然想救世

就算積儲獻盡飢荒赤地
而太多債沒處理
累人累己滋味 餘生也記起
數一數 我實情不只得你要說句對不起

良心有愧 原來隨便錯手
可毀了人一世
立志助世人脫貧以為
便偉大到像多麼有為
這種剌蝟 連誰曾待我好
都可帶來傷勢
被我害過來接受我跪
是我在製造眼淚居然想救世

良心有愧 原來隨便錯手
可毀了人一世
立志助世人脫貧以為
便偉大到像多麼有為
這種剌蝟 連誰曾待我好
都可帶來傷勢
內疚內疚內疚沒作為
直到某年某日我能安息於葬禮

仍想你一家可到齊

Firefox 3’s secure connection failed warning, shown when a website’s digital certificate is invalid or self-signed, can be easily disabled.

1. In the address bar, type about:config > click ‘Enter’.

2. You’ll get a warning message, This might void your warranty!, click I’ll be careful, I promise!

3. Double-click browser.ssl_override_behavior and change the value from ‘1’ to ‘2’.

4. Restart Firefox.

Instead of disabling the notice all together, you can have a warning displayed – without having to add an exception.

* browser.xul.error_pages.expert_bad_cert = true

The Cheat Sheet: All apps in one table

There you have it; we’ve covered the fundamental computing fronts out there with a nice mixture of applications (a majority of which are freeware) and where the commercial product still reigns we have at the very least covered a non-paid alternative.

You should now be able to browse the web and download torrents securely, watch or listen to almost anything you care to, chat with all of your buddies, keep up productivity for that deadline you’re facing next week and preserve some form of maintenance on your operating system.

Here’s a cheat sheet for your next fresh OS install:

* Italics denote a commercial/paid application

START TO ASK EXTRAORDINARY COMPUTER QUESTION PLEASE GO TO SEARCH ON GOOGLE OR YAHOO FIRST FOR YOUR OWN TASK IF YOU CAN ACCESS TO INTERNET. YOU MAY GET THE ANSWER FASTER THAN ASK IT PERSON IN SOME CASE. DO NOT BELIEVE THAT ALL REALTED TO COMPUTER QUESTION CAN BE GET THE ANSWER IMMEDIATELY FROM A IT PERSON. IT AND COMPUTER IS A VERY VERY GIGANTIC FIELD.

這是一篇非常有意義的文章

浮躁－你不應是Java程序員的風格

巴士，可能好多人日日都搭，不知大家又記起甚麼特別的事在巴士上發生。有次搭巴士，找了個二樓的位子坐。過了一會，我留意到有一男一女，一前一後的坐在windows邊位。兩人明顯是相識，二人正在聊天。不知可解，要分開坐，但又要聊天，辛苦自己。之後，車廂內開始多人，二人仍然無意坐在一起，還聊得很入神。又有人上車了，這位乘客就坐在正在聊天的女子旁的坐位。不過，這位女子不但沒有停口，還要在兩張椅子中間的位置與這位男子對話，還沒有停過口。想象一下這個情況，這位女子的口是十分接近這位乘客，不過那乘客到下車也沒有找別處坐，很有耐力。這一男一女的行為十分個性，不理會他人感受。