文件传输技术发展与产品趋势

HTTP 1.1 Features
Some of the more important improvements in version 1.1 are: Multiple Host Name Support: In HTTP/1.0, there was no way to specify the host name of the server to which the client needed to connect. As a result, the Web server at a particular IP address could only support one domain name. This was not only inefficient, it was exacerbating the depletion of IP addresses in the 1990s, because each new Web server to come online required a new IP address. HTTP/1.1 allows one Web server to handle requests for dozens or even hundreds of different virtual hosts.
网络蚂蚁
作者简介： 洪以容
1973年7月出生在上海，1991年进入上 海交通大学计算机系。 1995年毕业随后进入上海华腾软件有限 公司。 1998年考入上海交通大学计算机系攻读 系统结构专业研究生。 在他拿到研究生录取通知书以后的那段 时间里，他尝试开发出下载软件--网络 蚂蚁。 网络蚂蚁获得了巨大的成功，相继被国 内外的软件下载站点和权威媒体评为优 秀软件，得到了广大网民的认可和支持。
文件传输技术发展 与产品趋势
龚 少 卓
Hale Waihona Puke Baidu史前巨兽
目 录
Part I 技术演变 Part II 网游下载器 Part III 产品发展趋势
中国互联网发展大事记1994-1996
1994年4月20日，NCFC通过美国Sprint公司连入Internet的64K国际专线开通，实现了与Internet的全 功能连接。从此中国被国际上正式承认为真正拥有全功能Internet的国家。 1994年5月15日，中国科学院高能物理研究所设立了国内第一个WEB服务器，推出中国第一套网页，有 一个栏目叫“Tour in China”。此后并改名为《中国之窗》。 1994年5月，国家智能计算机研究开发中心开通曙光BBS站，这是中国大陆的第一个BBS站。 1994年6月8日，金桥前期工程建设全面展开。（1993年3月12日，时任副总理的朱镕基提出，地面骨干 网卫星通信网、无线移动数据用户接入网、光纤城域用户接入网） 1994年9月，中美双方签订关于国际互联网的协议，电信总局将通过美国Sprint公司开通2条64K专线(一 条在北京，另一条在上海)。中国公用计算机互联网(CHINANET)的建设开始启动。 1995年3月，中国科学院完成上海、合肥、武汉、南京四个分院的远程连接(使用IP/X.25技术)，开始了 将Internet向全国扩展的第一步。 1995年8月，金桥工程初步建成，在24省市开通联网(卫星网)，并与国际网络实现互联。 1995年12月，"中国教育和科研计算机网(CERNET)示范工程"建设完成，该工程由中国自行设计、建设。 1996年1月，中国公用计算机互联网(CHINANET)全国骨干网建成并正式开通，全国范围的公用计算机互 联网络开始提供服务。 1996年12月，中国公众多媒体通信网(169网)开始全面启动，广东视聆通、四川天府热线、上海热线作为 首批站点正式开通。
V1.25后停止开发
网络蚂蚁时期的技术特性： ·断点续传 ·多线程下载 ·多任务并行下载 ·支持HTTP/FTP协议
怀旧一下
目 录
FTP 1963
HTTP 1997
P2P P2SP
P4P
uTP 2009
？ 2012
1999 2003 2008
HTTP
HTTP/0.9 The original version of HTTP was intended only for the transfer of hypertext documents, and was designed to be very simple to make implementation of the fledgling Web easier. This early HTTP specifies that an HTTP client establishes a connection to an HTTP server using TCP. The client then issues a single “GET” request specifying a resource to be retrieved. The server responds by sending the file as a stream of text bytes, and the connection is terminated. The entire document defining this version of HTTP is only a couple of pages long! HTTP/1.0 The skeleton of functionality that HTTP/0.9 formed the basis for a rapid evolution of HTTP in the early 1990s. As the World Wide Web grew in size and acceptance, many new ideas and features were incorporated into HTTP. The result of a great deal of development effort was the formalization of the first HTTP standard: version 1.0. This much enhanced HTTP was published in May 1996 as RFC 1945, Hypertext Transfer Protocol — HTTP/1.0. It had been in use for several years prior to that formal publication date, however. HTTP/1.1 While impatient pundits coined sarcastic terms such as the “World Wide Wait”, the IETF continued to work to improve HTTP. In January 1997, the first draft version of HTTP/1.1 appeared: in RFC 2068. This document was later revised and published as RFC 2616, Hypertext Transfer Protocol — HTTP/1.1, in June 1999. HTTP/1.1 retains backwards compatibility with both HTTP/1.0 and HTTP/0.9. It is accompanied by RFC 2617, HTTP Authentication: Basic and Digest Access Authentication, which deals with security and authentication issues.
为什么现在的下载服务器都采用HTTP而不是FTP？
% ftp cs.colorado.edu Connected to cs.colorado.edu. 220 bruno FTP server (SunOS 4.1) ready. Name (cs.colorado.edu:yourlogin): anonymous 331 Guest login ok, send ident as password. Password: 230-This server is courtesy of Sun Microsystems, Inc. 230230 Guest login ok, access restrictions apply. ftp> cd /pub/HPSC 250 CWD command successful. ftp> ls 200 PORT command successful. 150 ASCII data connection for /bin/ls (128.138.242.10,3133) (0 bytes). ElementsofAVS.ps.Z 226 ASCII Transfer complete. 418 bytes received in 0.043 seconds (9.5 Kbytes/s) ftp> get ElementsofAVS.ps.Z 200 PORT command successful. 150 ASCII data connection for ElementsofAVS.ps.Z (128.138.242.10,3134) (2881 bytes). 226 ASCII Transfer complete. local: README remote: ElementsofAVS.ps.Z 2939 bytes received in 0.066 seconds (43 Kbytes/s) ftp> bye 221 Goodbye.
Persistent Connections: HTTP/1.1 allows a client to send multiple requests for related documents to a server in a
single TCP session. This greatly improves performance over HTTP/1.0, where each request required a new connection to the server. Partial Resource Selection: In HTTP/1.1, a client can ask for only part of a resource rather than the entire document, which reduces the load on the server and saves transfer bandwidth. Better Caching and Proxying Support: HTTP/1.1 includes many provisions to make caching and proxying more efficient and effective than they were in HTTP/1.0. These techniques can improve performance by providing clients with faster replies to their requests while reducing the load on servers, as well as enhancing security and implementing other functionality. Content Negotiation: A negotiation feature was added that allows the client and server to exchange information to help select the best resource or version of a resource when multiple variants are available. Better Security: HTTP/1.1 defines authentication methods and is generally more “security aware” than HTTP/1.0 was.
目 录
Part I 技术演变
FTP 1971
HTTP P2P 1997
P2SP
P4P
uTP 2009
？ 2012
1999 2003 2008
FTP
"The first FTP standard was RFC 114, published in April 1971, before TCP and IP even existed."