打羽毛球如何握拍——有图片和文字说明

打羽毛球如何握拍——有图片和文字说明: "打羽毛球如何握拍——有图片和文字说明
作者：未知 文章来源：互联网 点击数：102 更新时间：2009-6-24 【字体：小 大】

* 了解羽毛球拍的手柄
* 正手握拍技术
* 反手握拍技术
* 初学者常见的握拍错误
* 练习方法
* 握拍技巧


一、了解羽毛球拍的手柄

球拍手柄的基本外形：注意图中标出的A点那条棱为握拍时虎口要对准位置

球拍手柄的基本外形



有人曾作过这样的比喻：“羽毛球的球拍是选手手臂的延伸。”正确的握拍可使其与人的手有机地融为一体，选手可用这只“延长的手”随心所欲地迎击不同方向、不同速度的来球达到手与球拍之间完美的结合。

羽毛球的握拍分为正手握拍和反手。但对于一名高水平的选手来说，握拍又不是一成不变的。在实战中为了更好地控制球的落点，应视具体情况，因时、因地细微地调整握拍，但所有这些调整都是建立在正、反手两种基本握拍技术的基础上的。
一、正手握拍技术

以下介绍的所有基本技术均以右手握拍者为例，左手持拍者则反之。一切在身体右侧的正手正拍面击球及头顶后场击球都采用正手握拍法，正手握拍技术动作要领是：

1、先用左手握住球拍的中杠，使拍框与地面垂直。

2、张开右手，使虎口对准拍柄斜棱上的第二条棱线，此时眼睛从左至右可同时看见四条棱线，然后用近似握手的方法握住拍柄，拇指和食指贴在拍柄两侧的宽面上，其余的三指自然握住拍柄。

3、拍柄与掌心不要握紧，应留有空隙。握拍的位置可视各人的情况而定，一般情况下，以球拍柄端靠近手掌的小鱼际为益。

4、握拍力度适宜，恰似握着一个鸡蛋，重则破损，轻则滑落。

正手握拍：握拍不要很紧，要尽量放松握拍手指。 发力时才要握紧。

握拍不要很紧，要尽量放松握拍手指。 发力时才要握紧

正手握拍时虎口要对准A棱
二、反手握拍技术

一切在身体左侧的反手反拍面击球都采用反手握拍法，反手握拍技术的动作要领是：

1、在正手握拍的基础上，将球拍柄稍向外旋，拇指顶贴在拍柄第一斜棱旁的宽面上，也可将大拇指放在第一、二斜棱之间的小窄面上，食指稍向下靠。

2、击球时，靠食指以后的三指紧握拍柄，同时拇指前顶发力击球。

3、为了便于发力，掌心与拍柄间要留有充分的空隙。

掌心与拍柄间要留有充分的空隙

掌心与拍柄间要留有充分的空隙


三、初学者常见的握拍错误

1、虎口对在第一、第三或第四条斜棱上或者拍柄宽面上。

2、如同握拳头一样地将拍柄紧紧攥住。

3、食指按在拍柄宽面的上部，而仅用其余四指攥住球拍。

反手 握拍：除了握拍角度不同外，握拍力度和发力方式同上相同。
四、练习步骤

1、让握拍手自由转动拍柄后，按照正确的技术动作要领，用肉眼观察由握拍手独立调整完成呈正手握拍动作或反手握拍动作。

2、通过反复练习，逐渐过渡到不用肉眼观察，全凭手上的感觉便可完成正确握拍。

3、在实战中，视来球的各种不同角度和方向，握拍手可自如地选择正手或反手握拍法击球，握拍力度应适宜。
其它握拍技巧

其它握拍主要手指图解：处理网前球时，主要靠拇指和食指来控制球拍，其它手指为辅助指。

处理网前球时，主要靠拇指和食指来控制球拍，其它手指为辅助指

处理中后场球时，主要靠无名指和小指来握拍，其它手指要虚握，为发力留出空间

处理中后场球时，主要靠无名指和小指来握拍，其它手指要虚握，为发力留出空间


文章录入：hioffice 责任编辑：hioffice
# 上一篇文章： 拿拍的前后变换的技巧"

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我需要韓文輸入法對照表 ! - Yahoo!奇摩知識+

我需要韓文輸入法對照表 ! - Yahoo!奇摩知識+: "我需要韓文輸入法對照表 !
發問者： →Ａｌｗａｙｓ‧寶貝☆〃 ( 初學者 5 級)
發問時間： 2006-05-11 19:00:14
解決時間： 2006-05-14 13:39:59
解答贈點： 15 ( 共有 0 人贊助 )
回答：
1 評論： 0 意見： 1
網友正面評價 96% ( 共有 56 人評價 )
[ 檢舉 ]
我需要韓文輸入法的對照表，
現在的輸入法應該都是ＸＰ內建的吧
有哪位大大可以提供我對照表呢？
感激唷！

* 2006-05-11 19:01:16 補充

對了，請順便標明來源唷！

我對陌生的檔案有恐懼。。。

再次感激︿︿

最佳解答

* 發問者自選

回答者： Marshmallow ( 研究生 3 級 )
回答時間： 2006-05-11 21:00:18
[ 檢舉 ]

1.韓文輸入法：

如果你的電腦window是xp以上（印象中），按以下作法～～

先從
我的電腦／控制台／地區及地方語言選項／語言（標籤）／（點選）詳細資料／設定（標籤）／新增／增加韓文輸入法，之後按確定後再按一個確定，這樣應該就有韓文輸入法！

如果有韓文輸入法，在電腦最右下方，有語言列，你可以選韓文這樣就可以輸入韓文了！有「Ａ」「가」，A是英文輸入，「가」就是韓文輸入！

鍵盤配製如下：

ㅁ是A ㄹ是F ㅓ是J

ㅂㅈㄷㄱㅅ ㅛㅕㅑㅐ(ㅒ) ㅔ(ㅖ)
ㅁㄴㅇㄹㅎ ㅗㅓㅏㅣ
ㅋㅌㅊㅍㅠ ㅜㅡ

O為ㅐ O+shift為ㅒ P為ㅔ　P+shift為ㅖ
如果是硬音如ㅆ只要T＋shift即可！ㅃ則是Ｑ＋shift，硬音就由於類推！


這裡有韓文輸入對照表～～


圖片來源 http://www.gtv.com.tw/TalkAbout/TalkReply.asp?SID=135368

2.韓文輸入法

WINDOWS XP 的方式 完全設定Step by Step!

1.打開控制台
2.選[地區及語言] 選項
3.進入[語言]部份
4.會看到[文字輸入和輸入語言] 按下[詳細資料]鍵
5.看到 [已安裝服務] 按下[新增]
6.輸入語言請找到[韓文] (在倒數第三個吧) 並且將[鍵盤配置/輸入法] 前面的空格打勾--鍵盤同樣要對應到[Korean Input System(IME 2002)]..然後按[確定]
7.跳回[設定]這一層,記得再按[確定] 之後就可以跳出來了..

8.此時 應該可以看到 螢幕右下方平常輸入法的部分有一個CH的字樣
(CH=Chinese中文輸入)
9.用滑鼠左鍵點選 CH 會出現另一個選項 KO 韓文, 點選KO 就切換到韓文輸入介面了!
10. 之後的輸入 請對照 下圖 [韓文輸入對照鍵盤位置] 去進行
11. 要回復使用中文輸入時, 請同樣用滑鼠左鍵點選 KO 字樣~切換回 CH就可以了!
韓文輸入鍵盤對照表如下：　


（把這張圖copy下來，列印出來貼在電腦鍵盤旁或者螢幕旁）

來源:

http://www.backpackers.com.tw/forum/viewtopic.php?p=67681

＊兩個使用法都一樣，讓你選擇囉^^
參考資料 +ㄱ ㄴ ㄷ +

相關詞：

* 韓文翻譯,
* 學韓文,
* 韓文歌,
* 韓文歌詞,
* 韓文系,
* 好聽的韓文歌,
* 韓文教學,
* 韓文補習班,
* 韓文發音,
* 韓文輸入法

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Incoming and Outgoing Mail Server Settings for Hotmail, Yahoo, Google GMail, AOL and more

Incoming and Outgoing Mail Server Settings for Hotmail, Yahoo, Google GMail, AOL and more: "Home > Outlook & Email Tips > Incoming and Outgoing Mail Server Settings
Digital Software Development Outlook RSS Feeds
Incoming and Outgoing Mail Server Settings for Hotmail, Yahoo! Mail, GMail, AOL and more

*Update, 29th of August 2006: the Google Gmail service offers a SMTP server (outgoing mail server) for Gmail accounts. To use the Google Gmail SMTP server, use the following information:

Google Gmail Outgoing Mail Server (SMTP): smtp.gmail.com

The Gmail SMTP server requires authentication (use the same settings as for the incoming mail server)

The Google Gmail SMTP Server requires an encrypted connection (SSL) on port 465.

dots Why & when do I need these settings?

Hotmail, Yahoo! Mail, GMail and other providers are basically email services designed to provide you with email mailbox accesss directly from the web. However, going online and logging on to their sites is not always the most convenient way for reading and sending emails.

On the other hand, you have the alternative to send and receive emails through such a mailbox by using a local email client software, such as Outlook Express, Microsoft Outlook, Thunderbird, Thunderbird, etc. In order to properly use it, you need to configure your email software with the incoming and outgoing mail servers of your email provider (Hotmail, Gmail, Yahoo! Mail or else).
dots Mail Server Settings

# Hotmail Settings

As other web based email services, Hotmail is using the HTTP protocol for connecting you to your mailbox. If you want to send and receive Hotmail emails using an email client software, then your software must support Hotmail HTTP access for your email account. Some email clients, such as Outlook Express or Microsoft Outlook, offer builtin support for Hotmail accounts, so you only have to select HTTP when you are asked to select your email account type and select Hotmail as the HTTP Mail Service Provider.

# Yahoo! Mail Settings

Unlike Hotmail, Yahoo! Mail offers standard POP3 access for receiving emails incoming through your Yahoo mailbox, by using your favorite email client software. To setup your email client for working with your Yahoo account, you need to select the POP3 protocol and use the following mail server settings:

Yahoo Incoming Mail Server (POP3) - pop.mail.yahoo.com (port 110)

Yahoo Outgoing Mail Server (SMTP) - smtp.mail.yahoo.com (port 25)

# Google GMail Settings

The Google GMail service offers email client access for retrieving and sending emails through your Gmail account. However, for security reasons, GMail uses POP3 over an SSL connection, so make sure your email client supports encrypted SSL connections.

Google Gmail Incoming Mail Server (POP3) - pop.gmail.com (SSL enabled, port 995)

Outgoing Mail Server - use the SMTP mail server address provided by your local ISP or smtp.gmail.com (SSL enabled, port 465)

# Lycos Mail Settings

The Lycos Mail Plus service allows you to use POP3 and SMTP servers for accessing your Lycos mailbox.

Lycos Mail Incoming Mail Server (POP3) - pop.mail.lycos.com (port 110)

Outgoing Mail Server - smtp.mail.lycos.com or use your local ISP SMTP mail server

# AOL Mail Settings

The AOL email service is a web based system, designed for managing your AOL mailbox via HTTP IMAP access. Unlike Hotmail, you can use any email client to access your AOL mailbox, as long as it supports the IMAP protocol.

AOL Incoming Mail Server (IMAP) - imap.aol.com (port 143)

AOL Outgoing Mail Server - smtp.aol.com or use your local ISP SMTP mail server

# Mail.com Mail Settings

The Mail.com email service allows you to use POP3 and SMTP servers for accessing your Mail.com mailbox.

Mail.com Mail Incoming Mail Server (POP3) - pop1.mail.com (port 110)

Outgoing Mail Server - use your local ISP SMTP mail server

# Netscape Internet Service Mail Settings

The Netscape e-mail system is web-based, which means you can access their e-mail from any Internet connection. Netscape Internet Service also supports AOL® Communicator, Microsoft® Outlook, Microsoft® Outlook Express, and other POP3 e-mail software. The outgoing mail server needs SSL support, so make sure your email client software supports SSL connections over the SMTP protocol.

Netscape Internet Service Incoming Mail Server (POP3) - pop.3.isp.netscape.com (port 110)

Netscape Internet Service Outgoing Mail Server - smtp.isp.netscape.com (port 25, using a secure SSL connection)

# Tiscali Mail Settings

The Tiscali email service allows you to use POP3 and SMTP servers for accessing your Tiscali mailbox.

Tiscali Incoming Mail Server (POP3) - pop.tiscali.com (port 110)

Outgoing Mail Server - use your local ISP SMTP mail server

# Freeserve Mail Settings

The Freeserve email service allows you to use POP3 and SMTP servers for accessing your Freeserve mailbox.

Freeserve Incoming Mail Server (POP3) - pop.freeserve.com (port 110)

Outgoing Mail Server - use your local ISP SMTP mail server

# Supanet Mail Settings

The Supanet email service allows you to use POP3 and SMTP servers for accessing your Supanet mailbox.

Supanet Incoming Mail Server (POP3) - pop.supanet.com (port 110)

Outgoing Mail Server - use your local ISP SMTP mail server

If your email client does not support Hotmail as a Mail Service Provider or if it simply doesn't work with your mail server settings, you can use a 3rd party solution like Hotmail Popper, IzyMail, POP Peeper or Email2Pop. When using such tools, you should define your Hotmail account as a POP3 account and you will need to define your incoming mail server will as 'localhost' (or 127.0.0.1). Back to the Email Tips Index."

I need settings yahoo POP3 and SMTP? - Yahoo! Answers

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I need settings yahoo POP3 and SMTP?

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Incoming mail server (POP3): pop.mail.yahoo.com
Outgoing mail server (SMTP): smtp.mail.yahoo.com

Yahoo expressively states, that Outlook, Outlook Express and other progs like Incredimail only work with mail plus, but by using 'YPOPs!' you can get Outlook to work with Yahoo! mail regular and New Yahoo! mail too.

http://ypopsemail.com/

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If you want to use Outlook, Outlook Express, Thunderbird or other third party email clients to view your email you have 2 options.
Subscribe to mail plus:
http://billing.mail.yahoo.com/bm/Upgrade…

or download and install YPOPS
http://ypopsemail.com/


then follow the directions for your version of outlook here,

http://help.yahoo.com/l/us/yahoo/mail/or…

If you have trouble with set up, check the YPOPS installation page for alternate set up instructions.

http://dbeusee.home.comcast.net/
Click on YPOPS link on the left.
Then Click on Configuring email clients towards the bottom.
Choose the appropriate link for your mail client.

I currently utilize version 2.0.0.4 of Thunderbird
and version 0.8.3 of YPOPS (there is a more recent version of YPOPS that you need if you are Yahoo Beta Mail) and have no problems.
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Open Questions in External Mail (POP)

* Can we use ymail and rocketmail through MS outlook.is it a paid service?
* Can I be able to retrieve and send emails from my phone using my yahoo email address. What are the settings?
* How to Configuration gmail in outlook 2003?
* Outlook express MAJOR PROBLEM!?

Resolved Questions in External Mail (POP)

* yahoo email name help???
* Outlook Concern: Steps to Take?
* I moved, forwarded my mail to a temp address. Can I now change the forwarded address to another address?
* Adding Accounts to Outlook?

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PPStream – 免費讓您看遍全球電視、影片

PPStream – 免費讓您看遍全球電視、影片: "PPStream – 免費讓您看遍全球電視、影片
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分類: 免費軟體, 影音工具 | 2008-05-04 @ 22:01 （文章錯誤回報）

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常出差在外或是租屋沒有電視可以看、又嫌第四台貴嗎？那麼來用用這個採用P2P技術的網路電視吧。他打著﹝越多人看越穩定﹞的口號，正好跟P2P的核心精神相似；而經過數年的發展後其用戶越來越多、頻道及節目品質也不斷在提升，成為網路電視裡首屈一指的翹楚。更特別的是，他不只能用軟體觀看、還可以嵌在網頁上讓您想看就看、一點都不費工夫。目前能線上收看電影、電視劇、體育直播、遊戲競技、動漫、綜藝、新聞、財經資訊……播放相當流暢、更棒的是他是免費的。

很想試試這個很棒的軟體嗎？趕快到以下網址下載安裝觀看，保證您不再無聊、不再只能用電腦工作喔。

【網站網址】http://www.pps.tv/"

Postpet clock もっと楽しく｜Webメール｜ポストペット

もっと楽しく｜Webメール｜ポストペット

MIROKO – 免費5GB網路硬碟，中文介面，兼具BT代抓、網路相簿與檔案同步等功能！

MIROKO – 免費5GB網路硬碟，中文介面，兼具BT代抓、網路相簿與檔案同步等功能！: "MIROKO – 免費5GB網路硬碟，中文介面，兼具BT代抓、網路相簿與檔案同步等功能！
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分類: 1GB(含)以上, 免費空間 | 2009-06-18 @ 14:00 （文章錯誤回報）
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miroko.jpg

miroko是台灣新世紀資通（Seednet, 原數位聯合電信）所推出的網路硬碟服務，除了有一般遠端儲存檔案的功能外，miroko也有個人網頁、個人相簿與續傳功能，並加入了BT代抓、HTTP代抓和FTP代抓，集合所有功能於一身，使用者無須付費就能夠使用，註冊後可立即獲得5GB的超大容量與2GB每日分享上限。

而miroko也有自己的專屬軟體，使用者可以選擇是否安裝，安裝後就能夠直接以拖拉方式來上傳下載檔案，或是達成兩地的異地同步更新與資料安全備份功能。

註冊miroko帳號

1. 進入miroko首頁，點選右方的立即加入按鈕。

miroko-01.png

2. 依序輸入帳號、E-Mail、密碼與驗證碼。

miroko-02.png

3. 接著到信箱收信，必須在三天內點選驗證連結以開啟你的帳號。

miroko-03.png

到這裡為止，你已經完成註冊並擁有一個miroko帳號囉！接著我會帶領大家瞭解miroko的介面與操作方式。
安裝 miroko 程式

miroko提供的程式容量不大，安裝後就能讓本機電腦與遠端達成檔案同步，或直接以拖曳方式來上下傳檔案，非常方便。

miroko下載網址：http://www.miroko.tw/downloadLatestMiroko （或是在登入miroko後找到下載連結）

1. 點選安裝程式，選擇你要安裝的目錄路徑。

miroko-09.png

2. 稍待片刻後就會安裝完成，然後輸入你所註冊的miroko帳號密碼進行登入。

miroko-10.png

3. 登入後，miroko會常駐於右下角工具列，點選之後會開啟瀏覽器進入你的miroko網路硬碟，你就可以發現檔案管理員左側出現本機硬碟的檔案囉！（右方為網路硬碟，可以直接拖曳檔案來上傳或下載）。

miroko-11.png
miroko上下傳檔案

1. 如果你不想安裝miroko軟體，也可以直接在miroko首頁登入帳號。登入後可以看到你的空間與流量使用情形，而主選單則是在下方。

miroko-04.png

2. 點選下方的檔案，可以看到網路硬碟內的文件，點選上方「上傳檔案」就能透過瀏覽器將電腦內的檔案上傳到網路硬碟。

miroko-05.png

3. 選擇欲上傳的檔案與目錄，接著按下開始上傳。

miroko-06.png

這樣檔案就會被上傳到miroko網路硬碟囉！
透過miroko代抓BT！

前面有提到，miroko提供BT代抓的服務，如果你是個喜歡從網路下載資料的使用者，又不想將電腦開一整天浪費電的話，可以考慮使用miroko來幫你下載BT檔案。

1. 首先，將 .torrent 檔案上傳到 miroko 內（前面有提到上傳方式）。接著點選下方選單的「背景工作」，從左方找到「BT」接著選擇你的BT檔案與檔案下載目錄。

miroko-07.png

2. 可以看到miroko開始下載我所加入的BT檔案！

miroko-08.png

等到完成下載後，你就可以從miroko網路硬碟內，將檔案下載回自己電腦。
將照片傳到miroko，建立相簿

1. 將照片直接拖曳到miroko「我的文件」內的「我的相簿」資料夾。

miroko-12.png

2. 點選背景工作，可以看到檔案上傳進度。

miroko-13.png

3. 上傳完成後，選擇下方的「相簿預覽」，接著點選「相簿更新」。

miroko-14.png

4. 稍待片刻就能在你的個人相簿中看到以 SimpleViewer 所展示的動態相簿。

範例相簿：http://pseric.miroko.tw/photo/

miroko-15.png

【網站網址】miroko"

GMX – 超大5GB免費信箱，網址短、外加1GB網路硬碟！

GMX – 超大5GB免費信箱，網址短、外加1GB網路硬碟！: "GMX – 超大5GB免費信箱，網址短、外加1GB網路硬碟！
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分類: 電子信箱 | 2009-06-30 @ 14:00 （文章錯誤回報）
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GMX Logo

GMX Free E-Mail 結束了beta測試階段，正式加入免費信箱戰場。除了提供簡短、好記的郵件地址（@gmx.com）以外，更有超大的5GB信箱空間加上1GB的免費網路硬碟，使用者也能將它結合桌面成為一個虛擬的遠端硬碟。除此之外，GMX信箱 提供免費的POP3與IMAP權限，也就是說你也可以直接從GMX收取其他信箱的E-Mail信件。


信箱資訊

【容量空間】5GB（附件50MB）、網路硬碟1GB
【地址格式】你的帳號@gmx.com
【垃圾過濾】有，已內建（可關閉）。
【病毒掃描】有，已內建。
【其他功能】支援 POP3, SMTP, IMAP，可設定自動回覆。

【網站網址】http://www.gmx.com/service/
【申請網址】http://www.gmx.com/service/registration.html

* POP3：pop.gmx.com
* SMTP：mail.gmx.com
* IMAP4：imap.gmx.com

註冊帳號

1. 進入 GMX 首頁，點選 Sign Up Now，或是在下方輸入一個帳號檢查是否有人註冊。

點選 Sign Up Now 註冊

2. 接著輸入個人資料，包括性別（Gender）、名（First Name）、姓氏（Last Name）、生日（Date of Birth）與國籍（Country），然後在 Desired E-Mail Address 欄位輸入你想要使用的信箱地址，按下 Check Availability 後可以檢查是否可用。

輸入你想使用的 E-Mail 帳號

最後別忘記設定密碼與輸入驗證碼，就可以進行註冊。

3. 完成註冊後第一次進入GMX信箱，會提示使用者是否要設定收取其他外部信箱的郵件，如果不急著現在設定，可以按右下方的 Go to GMX Mail。

可以設定收取外部 E-Mail

不希望 GMX Mail 下次再顯示這個訊息嗎？將下方的框框勾選即可。下圖就是 GMX Mail 的主畫面了，是不是看起來相當親和呢？

GMX 信箱主畫面

在 Settings 設定選項裡，還能看到 Spam Protection（垃圾郵件防護）與 Virus Portection（病毒防護）功能正常啟動中，不過很奇怪的是 GMX 也允許使用者將垃圾郵件防護功能關掉。

GMX Spam Protection & Virus Protection
GMX’s File Storage（網路硬碟）

1. 使用者可以在登入信箱後，於左下方找到 File Storage 也就是網路硬碟功能。

點選左下方 File Storage 進入網路硬碟

2. 可以看到每位使用者將可以使用1GB超大容量！支援所有檔案類型，包括文字、圖片、音樂或影片等等，而且檔案傳輸將會以SSL加密，遏止有心人士竊取資料，使用者也可以設定管理訪客權限。

GMX File Storage Features

3. 操作方式也很簡單，例如我進入了 My Photos 目錄，然後按下滑鼠右鍵，選擇 Upload File(s) 就可以將檔案上傳進來。

點選右鍵、選擇 Upload File(s) 上傳檔案

4. 上傳完成後，如果要將目錄分享給其他人，你必須先將檔案拖曳到 New File Attachments 目錄，然後點選上方的 Sharing ，然後選擇 Share Folder 後填入對方的信箱即可。

分享目錄內的檔案。

5. 填入信箱、郵件主旨、訊息與分享名稱，你也可以將上密碼來增加安全性。

輸入 E-Mail Address, 郵件主旨、內容與分享名稱

6. 對方會收到一封來自 GMX 的通知信，點選信中連結，會進入如下的頁面，透過訪客權限來存取使用者分享的目錄。

以 Guest 權限存取目錄

7. 這樣其他人就可以從你的網路硬碟下載檔案囉！

按下 Save As ... 即可下載檔案

當然，GMX Free E-Mail 的功能不僅於此，我們只列舉了部份使用者可能會較常用到的功能。目前 GMX 已有超過 1,100 萬名的使用者，實力不容小覷，相信未來能不斷開發並提供更多優質的服務，且讓我們拭目以待吧！"

PatternCooler | Cool Seamless Background Pattern Designs for Web and Graphic Projects, Blogs, Twitter, MySpace, Mobile Phone Wallpapers,

PatternCooler | Cool Seamless Background Pattern Designs for Web and Graphic Projects, Blogs, Twitter, MySpace, Mobile Phone Wallpapers,

PIXLR – 免費網頁版 PHOTOSHOP，無須安裝，立即使用！

PIXLR – 免費網頁版 PHOTOSHOP，無須安裝，立即使用！: "PIXLR – 免費網頁版 PHOTOSHOP，無須安裝，立即使用！
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pixlr

用一句最貼切的話來形容 pixlr，那就是︰

把 Photoshop 搬到瀏覽器裡頭使用。

剛進這個網站，沒仔細看還以為不小心開到 Photoshop 了呢！目前 pixlr 服務完全免費，除了提供免費圖片編輯器外，也提供簡易的照片修圖工具，介面採用全 flash 運作，只要你的瀏覽器支援 flash 的話就可以使用啦！

Online Image Editor - pixlr
如何開始？

1. 進入 pixlr 首頁後，點選 Jump in n’ get started! 啟動圖片編輯工具。

點選上頁 Jump in n' get started! 啟動圖片編輯工具

進入網站之後，pixlr會要求使用者選擇圖片的來源，你可以建立一個新圖片、從本機電腦上傳或是直接開啟圖片網址。

pixlr 提供三種圖片載入方式

英文介面讓你看得一頭霧水嗎？沒關係，pixlr提供多國語言介面，不管你是土耳其來的，還是韓國來的，都有你要的語言喔！當然，也有繁體中文，選擇 Languages 內的 Traditional Chinese 就可以切換為正體中文。

上方的 Languages 可以選擇介面語言

pixlr提供數十種濾鏡，使用方式非常簡單，在上方的工具列選擇濾鏡，就可以直接套用並且預覽效果。

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Blowfish Paper

Blowfish Paper: "Description of a New Variable-Length Key, 64-Bit Block Cipher (Blowfish)

B. Schneier

Fast Software Encryption, Cambridge Security Workshop Proceedings (December 1993), Springer-Verlag, 1994, pp. 191-204.

ABSTRACT:

Blowfish, a new secret-key block cipher, is proposed. It is a Feistel network, iterating a simple encryption function 16 times. The block size is 64 bits, and the key can be any length up to 448 bits. Although there is a complex initialization phase required before any encryption can take place, the actual encryption of data is very efficient on large microprocessors.

The cryptographic community needs to provide the world with a new encryption standard. DES [16], the workhorse encryption algorithm for the past fifteen years, is nearing the end of its useful life. Its 56-bit key size is vulnerable to a brute-force attack [22], and recent advances in differential cryptanalysis [1] and linear cryptanalysis [10] indicate that DES is vulnerable to other attacks as well.

Many of the other unbroken algorithms in the literature--Khufu [11,12], REDOC II [2,23, 20], and IDEA [7,8,9]--are protected by patents. RC2 and RC4, approved for export with a small key size, are proprietary [18]. GOST [6], a Soviet government algorithm, is specified without the S-boxes. The U.S. government is moving towards secret algorithms, such as the Skipjack algorithm in the Clipper and Capstone chips [17].

If the world is to have a secure, unpatented, and freely- available encryption algorithm by the turn of the century, we need to develop several candidate encryption algorithms now. These algorithms can then be subjected to years of public scrutiny and cryptanalysis. Then, the hope is that one or more candidate algorithms will survive this process, and can eventually become a new standard.

This paper discusses the requirements for a standard encryption algorithm. While it may not be possible to satisfy all requirements with a single algorithm, it may be possible to satisfy them with a family of algorithms based on the same cryptographic principles.

AREAS OF APPLICATION

A standard encryption algorithm must be suitable for many different applications:

Bulk encryption. The algorithm should be efficient in encrypting data files or a continuous data stream.

Random bit generation. The algorithm should be efficient in producing single random bits.

Packet encryption. The algorithm should be efficient in encrypting packet-sized data. (An ATM packet has a 48- byte data field.) It should implementable in an application where successive packets may be encrypted or decrypted with different keys.

Hashing. The algorithm should be efficient in being converted to a one-way hash function.

PLATFORMS

A standard encryption algorithm must be implementable on a variety of different platforms, each with their own requirements. These include:

Special hardware. The algorithm should be efficiently implementable in custom VLSI hardware.

Large processors. While dedicated hardware will always be used for the fastest applications, software implementations are more common. The algorithm should be efficient on 32-bit microprocessors with 4 kbyte program and data caches.

Medium-size processors. The algorithm should run on microcontrollers and other medium-size processors, such as the 68HC11.

Small processors. It should be possible to implement the algorithm on smart cards, even inefficiently.

The requirements for small processors are the most difficult. RAM and ROM limitations are severe for this platform. Also, efficiency is more important on these small machines. Workstations double their capacity almost annually. Small embedded systems are the same year after year, and there is little capacity to spare. If there is a choice, the extra computation burden should be on large processors rather than small processors.

ADDITIONAL REQUIREMENTS

These additional requirements should, if possible, be levied on a standard encryption algorithm.

The algorithm should be simple to code. Experiences with DES [19] show that programmers will often make implementation mistakes if the algorithm is complicated. If possible, the algorithm should be robust against these mistakes.

The algorithm should have a flat keyspace, allowing any random bit string of the required length to be a possible key. There should be no weak keys.

The algorithm should facilitate easy key-management for software implementations. Software implementations of DES generally use poor key management techniques. In particular, the password that the user types in becomes the key. This means that although DES has a theoretical keyspace of 256, the actual keyspace is limited to keys constructed with the 95 characters of printable ASCII. Additionally, keys corresponding to words and near words are much more likely.

The algorithm should be easily modifiable for different levels of security, both minimum and maximum requirements.

All operations should manipulate data in byte-sized blocks. Where possible, operations should manipulate data in 32-bit blocks.

DESIGN DECISIONS

Based on the above parameters, we have made these design decisions. The algorithm should:

Manipulate data in large blocks, preferably 32 bits in size (and not in single bits, such as DES).

Have either a 64-bit or a 128-bit block size.

Have a scalable key, from 32 bits to at least 256 bits.

Use simple operations that are efficient on microprocessors: e.g., exclusive-or, addition, table lookup, modular- multiplication. It should not use variable-length shifts or bit-wise permutations, or conditional jumps.

Be implementable on an 8-bit processor with a minimum of 24 bytes of RAM (in addition to the RAM required to store the key) and 1 kilobyte of ROM.

Employ precomputable subkeys. On large-memory systems, these subkeys can be precomputed for faster operation. Not precomputing the subkeys will result in slower operation, but it should still be possible to encrypt data without any precomputations.

Consist of a variable number of iterations. For applications with a small key size, the trade-off between the complexity of a brute-force attack and a differential attack make a large number of iterations superfluous. Hence, it should be possible to reduce the number of iterations with no loss of security (beyond that of the reduced key size).

If possible, have no weak keys. If not possible, the proportion of weak keys should be small enough to make it unlikely to choose one at random. Also, any weak keys should be explicitly known so they can be weeded out during the key generation process.

Use subkeys that are a one-way hash of the key. This would allow the use of long passphrases for the key without compromising security.

Have no linear structures (e.g., the complementation property of DES) that reduce the complexity of exhaustive search [4].

Use a design that is simple to understand. This will facilitate analysis and increase the confidence in the algorithm. In practice, this means that the algorithm will be a Feistel iterated block cipher [21].

Most of these design decisions are not new. Almost all block ciphers since Lucifer [5,21] are Feistel ciphers, and all have a flat keyspace (with the possible exception of a few weak keys). FEAL [13,14,15] and Khufu [11] use a variable number of iterations. Khufu [11] has a large number of subkeys that are a one-way function of the key. RC2 [18] has a variable-length key. GOST [6] uses a 32-bit word length and a 64-bit block size. MMB [2] uses a 32-bit word length and a 128-bit block size.

BUILDING BLOCKS

There are a number of building blocks that have been demonstrated to produce strong ciphers. Many of these can be efficiently implemented on 32-bit microprocessors.

Large S-boxes. Larger S-boxes are more resistant to differential cryptanalysis. An algorithm with a 32-bit word length can use 32-bit S-boxes. Khufu and REDOC III both use a 256-entry, 32-bit wide S-box [11,20].

Key-dependent S-boxes. While fixed S-boxes must be designed to be resistant to differential and linear cryptanalysis, key-dependent S-boxes are much more resistant to these attacks. They are used in the Khufu algorithm [11]. Variable S-boxes, which could possibly be key dependent, are used in GOST [6].

Combining operations from different algebraic groups. The IDEA cipher introduced this concept, combining XOR mod 216, addition mod 216, and multiplication mod 216+1 [7]. The MMB cipher uses a 32-bit word, and combines XOR mod 232 with multiplication mod 232-1 [2].

Key-dependent permutations. The fixed initial and final permutations of DES have been long regarded as cryptographically worthless. Khufu XORs the text block with key material at the beginning and the end of the algorithm [11].

BLOWFISH

Blowfish is a variable-length key block cipher. It does not meet all the requirements for a new cryptographic standard discussed above: it is only suitable for applications where the key does not change often, like a communications link or an automatic file encryptor. It is significantly faster than DES when implemented on 32-bit microprocessors with large data caches, such as the Pentium and the PowerPC.

DESCRIPTION OF THE ALGORITHM

Blowfish is a variable-length key, 64-bit block cipher. The algorithm consists of two parts: a key-expansion part and a data- encryption part. Key expansion converts a key of at most 448 bits into several subkey arrays totaling 4168 bytes.

Data encryption occurs via a 16-round Feistel network. Each round consists of a key-dependent permutation, and a key- and data-dependent substitution. All operations are XORs and additions on 32-bit words. The only additional operations are four indexed array data lookups per round.

Subkeys:

Blowfish uses a large number of subkeys. These keys must be precomputed before any data encryption or decryption.

1. The P-array consists of 18 32-bit subkeys:
P1, P2,..., P18.

2. There are four 32-bit S-boxes with 256 entries each:
S1,0, S1,1,..., S1,255;
S2,0, S2,1,..,, S2,255;
S3,0, S3,1,..., S3,255;
S4,0, S4,1,..,, S4,255.

The exact method used to calculate these subkeys will be described later.

Encryption:

Blowfish is a Feistel network consisting of 16 rounds (see Figure 1). The input is a 64-bit data element, x.

Divide x into two 32-bit halves: xL, xR
For i = 1 to 16:
xL = xL XOR Pi
xR = F(xL) XOR xR
Swap xL and xR
Next i
Swap xL and xR (Undo the last swap.)
xR = xR XOR P17
xL = xL XOR P18
Recombine xL and xR

Function F (see Figure 2):
Divide xL into four eight-bit quarters: a, b, c, and d
F(xL) = ((S1,a + S2,b mod 232) XOR S3,c) + S4,d mod 232

Decryption is exactly the same as encryption, except that P1, P2,..., P18 are used in the reverse order.

Implementations of Blowfish that require the fastest speeds should unroll the loop and ensure that all subkeys are stored in cache.

Generating the Subkeys:

The subkeys are calculated using the Blowfish algorithm. The exact method is as follows:

1. Initialize first the P-array and then the four S-boxes, in order, with a fixed string. This string consists of the hexadecimal digits of pi (less the initial 3). For example:

P1 = 0x243f6a88
P2 = 0x85a308d3
P3 = 0x13198a2e
P4 = 0x03707344

2. XOR P1 with the first 32 bits of the key, XOR P2 with the second 32-bits of the key, and so on for all bits of the key (possibly up to P14). Repeatedly cycle through the key bits until the entire P-array has been XORed with key bits. (For every short key, there is at least one equivalent longer key; for example, if A is a 64-bit key, then AA, AAA, etc., are equivalent keys.)

3. Encrypt the all-zero string with the Blowfish algorithm, using the subkeys described in steps (1) and (2).

4. Replace P1 and P2 with the output of step (3).

5. Encrypt the output of step (3) using the Blowfish algorithm with the modified subkeys.

6. Replace P3 and P4 with the output of step (5).

7. Continue the process, replacing all entries of the P- array, and then all four S-boxes in order, with the output of the continuously-changing Blowfish algorithm.

In total, 521 iterations are required to generate all required subkeys. Applications can store the subkeys rather than execute this derivation process multiple times.

MINI-BLOWFISH

The following mini versions of Blowfish are defined solely for cryptanalysis. They are not suggested for actual implementation. Blowfish-32 has a 32-bit block size and subkey arrays of 16-bit entries (each S-box has 16 entries). Blowfish-16 has a 16-bit block size and subkey arrays of 8-bit entries (each S-box has 4 entries).

DESIGN DECISIONS

The underlying philosophy behind Blowfish is that simplicity of design yields an algorithm that is both easier to understand and easier to implement. Through the use of a streamlined Feistel network--a simple S-box substitution and a simple P-box substitution--I hope that the design will not contain any flaws.

A 64-bit block size yields a 32-bit word size, and maintains block-size compatibility with existing algorithms. Blowfish is easy to scale up to a 128-bit block, and down to smaller block sizes. Cryptanalysis of the mini-Blowfish variants may be significantly easier than cryptanalysis of the full version.

The fundamental operations were chosen with speed in mind. XOR, ADD, and MOV from a cache are efficient on both Intel and Motorola architectures. All subkeys fit in the cache of a 80486, 68040, Pentium, and PowerPC.

The Feistel network that makes up the body of Blowfish is designed to be as simple as possible, while still retaining the desirable cryptographic properties of the structure. Figure 3 is round i of a general Feistel network: Rn,i are reversible functions of text and key, and Ni is a non-reversible function of text and key. For speed and simplicity, I chose XOR as my reversible function. This let me collapse the four XORs into a single XOR, since:

R--1,i+1 = R1,i+1 XOR R2,i-1 XOR R3,i XOR R4,i

This is the P-array substitution in Blowfish. The XOR can also be considered to be part of the non-reversible function, Ni, occurring at the end of the function. (Although equivalent, I chose not to illustrate them in this way because it simplifies description of the subkey-generation process.) There are two XORs that remain after this reduction: R1 in the first round and R2 in the last round. I chose not to eliminate these in order to hide the input to the first non-reversible function.

I considered a more complicated reversible function, one with modular multiplications and rotations. However, these operations would greatly increase the algorithm's execution time. Since function F is the primary source of the algorithm's security, I decided to save time-consuming complications for that function.

Function F, the non-reversible function, gives Blowfish the best possible avalanche effect for a Feistel network: every text bit on the left half of the round affects every text bit on the right half. Additionally, since every subkey bit is affected by every key bit, the function also has a perfect avalanche effect between the key and the right half of the text after every round. Hence, the algorithm exhibits a perfect avalanche effect after three rounds and again every two rounds after that.

I considered adding a reversible mixing function, more complicated than XOR, before the first and after the last round. This would further confuse the entry values into the Feistel network and ensure a complete avalanche effect after the first two rounds. I eventually discarded the addition as a time- consuming complication with no clear cryptographic benefits.

The non-reversible function is designed for strength, speed, and simplicity. Ideally, I wanted a single S-box with 232 32-bit words, but that was impractical. My eventual choice of 256-entry S-boxes was a compromise between my three design goals. The small-number of bits to large-number of bits may have weaknesses with respect to linear cryptanalysis, but these weaknesses are hidden both by combining the output of four S-boxes and making them dependent on the key.

I used four different S-boxes instead of one S-box primarily to avoid symmetries when different bytes of the input are equal, or when the 32-bit input to function F is a bytewise permutation of another 32-bit input. I could have used one S-box and made each of the four different outputs a non-trivial permutation of the single output, but the four S-box design is faster, easier to program, and seems more secure.

The function that combines the four S-box outputs is as fast as possible. A simpler function would be to XOR the four values, but mixing addition mod 232 and XOR combines two different algebraic groups with no additional instructions. The alternation of addition and XOR ends with an addition operation because an XOR combines the final result with xR.

If the four indexes chose values out of the same S-box, a more complex combining function would be required to eliminate symmetries. I considered using a more complex combining function in Blowfish (using modular multiplications, rotations, etc.), but chose not to because the added complication seemed unnecessary.

The key-dependent S-boxes protect against differential and linear cryptanalysis. Since the structure of the S-boxes is completely hidden from the cryptanalyst, these attacks have a more difficult time exploiting that structure. While it would be possible to replace these variable S-boxes with four fixed S-boxes that were designed to be resistant to these attacks, key-dependent S-boxes are easier to implement and less susceptible to arguments of 'hidden' properties. Additionally, these S-boxes can be created on demand, reducing the need for large data structures stored with the algorithm.

Each bit of xL is only used as the input to one S-box. In DES many bits are used as inputs to two S-boxes, which strengthens the algorithm considerably against differential attacks. I feel that this added complication is not as necessary with key- dependent S-boxes. Additionally, larger S-boxes would take up considerably more memory space.

Function F does not depend on the iteration. I considered adding this dependency, but did not feel that it had any cryptographic merit. The P-array substitution can be considered to be part of this function, and that is already iteration-dependent.

The number of rounds is set at 16 primarily out of desire to be conservative. However, this number affects the size of the P- array and therefore the subkey-generation process; 16 iterations permits key lengths up to 448 bits. I expect to be able to reduce this number, and greatly speed up the algorithm in the process, as I accumulate more cryptanalysis data.

In algorithm design, there are two basic ways to ensure that the key is long enough to ensure a particular security level. One is to carefully design the algorithm so that the entire entropy of the key is preserved, so there is no better way to cryptanalyze the algorithm other than brute force. The other is to design the algorithm with so many key bits that attacks that reduce the effective key length by several bits are irrelevant. Since Blowfish is designed for large microprocessors with large amounts of memory, I chose the latter.

The subkey generation process is designed to preserve the entire entropy of the key and to distribute that entropy uniformly throughout the subkeys. It is also designed to distribute the set of allowed subkeys randomly throughout the domain of possible subkeys. I chose the digits of pi as the initial subkey table for two reasons: because it is a random sequence not related to the algorithm, and because it could either be stored as part of the algorithm or derived when needed. There is nothing sacred about pi; any string of random bits--digits of e, RAND tables, output of a random number generator--will suffice. However, if the initial string is non-random in any way (for example, ASCII text with the high bit of every byte a 0), this non-randomness will propagate throughout the algorithm.

In the subkey generation process, the subkeys change slightly with every pair of subkeys generated. This is primarily to protect against any attacked of the subkey generation process that exploit the fixed and known subkeys. It also reduces storage requirements. The 448 limit on the key size ensures that the every bit of every subkey depends on every bit of the key. (Note that every bit of P15, P16, P17, and P18 does not affect every bit of the ciphertext, and that any S-box entry only has a .06 probability of affecting any single ciphertext block.)

The key bits are repeatedly XORed with the digits of pi in the initial P-array to prevent the following potential attack: Assume that the key bits are not repeated, but instead padded with zeros to extend it to the length of the P-array. An attacker might find two keys that differ only in the 64-bit value XORed with P1 and P2 that, using the initial known subkeys, produce the same encrypted value. If so, he can find two keys that produce all the same subkeys. This is a highly tempting attack for a malicious key generator.

To prevent this same type of attack, I fixed the initial plaintext value in the subkey-generation process. There is nothing special about the all-zeros string, but it is important that this value be fixed.

The subkey-generation algorithm does not assume that the key bits are random. Even highly correlated key bits, such as an alphanumeric ASCII string with the bit of every byte set to 0, will produce random subkeys. However, to produce subkeys with the same entropy, a longer alphanumeric key is required.

The time-consuming subkey-generation process adds considerable complexity for a brute-force attack. The subkeys are too long to be stored on a massive tape, so they would have to be generated by a brute-force cracking machine as required. A total of 522 iterations of the encryption algorithm are required to test a single key, effectively adding 29 steps to any brute-force attack.

POSSIBLE SIMPLIFICATIONS

I am exploring several possible simplifications, aimed at decreasing memory requirements and execution time. These are outlined below:

Fewer and smaller S-boxes. It may be possible to reduce the number of S-boxes from four to one. Additionally, it may be possible to overlap entries in a single S-box: entry 0 would consist of bytes 0 through 3, entry 1 would consist of bytes 1 through 4, etc. The former simplification would reduce the memory requirements for the four S-boxes from 4096 bytes to 1024 bytes, the latter would reduce the requirements for a single S-box from 1024 bytes to 259 bytes. Additional steps may be required to eliminate the symmetries that these simplifications would introduce. Additionally, four different 10- or 12-bit indexes into a single large S-box could be used instead of the current series of S-boxes.

Fewer iterations. It is probably safe to reduce the number of iterations from 16 to 8 without compromising security. The number of iterations required for security may be dependent on the length of the key. Note that with the current subkey generation procedure, an 8-iteration algorithm cannot accept a key longer than 192 bits.

On-the-fly subkey calculation. The current method of subkey calculation requires all subkeys to be calculated advance of any data encryption. In fact, it is impossible to calculate the last subkey of the last S-box without calculating every subkey that comes before. An alternate method of subkey calculation would be preferable: one where every subkey can be calculated independently of any other. High-end implementations could still precompute the subkeys for increased speed, but low-end applications could only compute the required subkeys when needed.

CONCLUSIONS

I conjecture that the most efficient way to break Blowfish is through exhaustive search of the keyspace. I encourage all cryptanalytic attacks, modifications, and improvements to the algorithm. Attacks on mini versions of Blowfish, those with a 32- or even a 16-bit block size, are also encouraged. Source code in C and test data can be provided to anyone wishing to implement the algorithm, in accordance with U.S. export laws.

The software magazine Dr. Dobb's Journal is sponsoring $1000 contest for the best cryptanalysis of Blowfish received before April 1995. Please contact me for details.

Blowfish is unpatented, and will remain so in all countries. The algorithm is hereby placed in the public domain, and can be freely used by anyone.

ACKNOWLEDGEMENTS

Much of the motivation for this algorithm, as well as the design criteria, was developed with Niels Fergusen. I would also like to thank Eli Biham, Agnes Chan, Peter Gutmann, Angel Johnston, Lars Kundsen, and Matt Robshaw for their helpful suggestions.

REFERENCES

1. E. Biham and A. Shamir, Differential Cryptanalysis of the Data Encryption Standard, Springer-Verlag, 1993.

2. T.W. Cusick and M.C. Wood, 'The REDOC-II Cryptosystem,' Advances in Cryptology--CRYPTO '90 Proceedings, Springer- Verlag, 1991, pp. 545-563.

3. J. Deamen, R. Govaerts, and J. Vandewalle, 'Block Ciphers Based on Modular Arithmetic,' Proceedings of the 3rd Symposium on State and Progress of Research in Cryptography, Rome, Italy, 15-16 Feb 1993, pp. 80-89.

4. J.-H. Evertse, 'Linear Structures in Blockciphers,' Advances in Cryptology--EUROCRPYT '87, Springer-Verlag, 1988, pp. 249- 266.

5. H. Feistel, 'Cryptography and Computer Privacy,' Scientific American, v. 228, n. 5, May 73, pp. 15-23.

6. GOST 28147-89, 'Cryptographic Protection for Data Processing Systems,' 'Cryptographic Transformation Algorithm,' Government Standard of the U.S.S.R., Inv. No. 3583, UDC 681.325.6:006.354. (in Russian)

7. X. Lai, J. Massey, and S. Murphy, 'Markov Ciphers and Differential Cryptanalysis,' Advances in Cryptology--EUROCRYPT '91 Proceedings, Springer-Verlag, 1991, pp. 17-38.

8. J.L. Massey and X. Lai, 'Device for Converting a Digital Block and the Use Thereof,' International Patent PCT/CH91/00117, 16 May 1991.

9. J.L. Massey and X. Lai, 'Device for the Conversion of a Digital Block and Use of Same,' U.S. Patent 5,214,703, 25 May 1993.

10. M. Matsui, 'Linear Cryptanalysis Method for DES Cipher,' Advances in Cryptology--CRYPTO '93 Proceedings, Springer- Verlag, 1994, in preparation.

11. R.C. Merkle, 'Fast Software Encryption Functions,' Advances in Cryptology--CRYPTO '90 Proceedings, Springer-Verlag, 1991, pp. 476-501.

12. R.C. Merkle, 'Method and Apparatus for Data Encryption,' U.S. Patent 5,003,597, 26 Mar 1991.

13. S. Miyaguchi, 'The FEAL-8 Cryptosystem and Call for Attack,' Advances in Cryptology--CRYPTO '89 Proceedings, Springer- Verlag, 1990, pp. 624-627.

14. S. Miyaguchi, 'Expansion of the FEAL Cipher,' NTT Review, v. 2, n. 6, Nov 1990.

15. S. Miyaguchi, 'The FEAL Cipher Family,' Advances in Cryptology--CRYPTO '90 Proceedings, Springer-Verlag, 1991, pp. 627-638.

16. National Bureau of Standards, Data Encryption Standard, U.S. Department of Commerce, FIPS Publication 46, Jan 1977.

17. National Institute of Standards and Technology, 'Clipper Chip Technology,' 30 Apr 1993.

18. RSA Laboratories, Answers to Frequently Asked Questions About Today's Cryptography, Revision 2.0, RSA Data Security Inc., 5 Oct 1993.

19. B. Schneier, 'Data Guardians,' MacWorld, Feb 1993, 145-151.

20. B. Schneier, Applied Cryptography, John Wiley & Sons, New York, 1994.

21. J.L Smith, The Design of Lucifer, A Cryptographic Device for Data Communication, RC 3326, White Plains: IBM Research.

22. M.J. Weiner, 'Efficient DES Key Search,' Advances in Cryptology--CRYPTO '93 Proceedings, Springer-Verlag, in preparation.

23. M.C. Wood, 'Method of Cryptographically Transforming Electronic Digital Data from One Form to Another,' U.S. Patent 5,003,596, 26 Mar 1991."

檔案保護精靈 – 加密個人資料，讓資料受到完善的保護！

檔案保護精靈 – 加密個人資料，讓資料受到完善的保護！