CS155a: E-CommerceNapster Client-Server InteractionNotes on Client-Server InteractionNapster Client-Client (P2P) InteractionNapster HistoryNapster History, continuedSlide 7Gnutella P2P File Sharing“A” Generates a Gnutella Request“B” Receives Gnutella Request (A, S, N, T)Gnutella Advantages and DisadvantagesSlide 12Gnutella HistoryFreenet P2P File SharingRealNetworks: An Internet Media Delivery SolutionRealNetworks OverviewRealNetworks Stock ChartRealNetworks Quarterly RevenuesRealNetworks Business ModelCompetition in the MarketRealNetworks Maintains Dominant Market Share“Daft Club” Model“Napster++ as Superdistribution” Model (Napster--??)“Street Performer” Model“Street Performer” Model (Cont.)“Hum A Few Bars” Model (K. McCurley, Financial Crypto ’00)Notable Business-Model ComponentsReading Assignment for October 4, 2001CS155a: E-CommerceLecture 8: October 2, 2001Business Models for OnlineContent DistributionNapster Client-Server Interaction Client1MP3-file1MP3-file2MP3-filenSearches a db of currently onlineusers for one that has previously stored therequested MP3.Adds client1 and its list to db.Removes client1 and its list from dbhelloackClient1’s IP addressNames of MP3s on Client1’s MachineRequestIP address of online user(client2) who has requested file [repeat]goodbyeackNotes on Client-Server Interaction• Proprietary protocol and db search. •No MP3 files stored on server.• Don’t need usernames. Could have made the service anonymous.• No need to save IP addresses between sessions. Many are assigned dynamically.• Discussion point: Are anonymity and memorylessness threats or opportunities for business?Napster Client-Client (P2P) InteractionClient1Client2Client1’s IP address Request Requested MP3Note: This part uses “standard Internet protocols,” e.g., FTPNapster History•1987: MP3 format developed by Karlheinz Brandenburg of Fraunhofer Gesellschaft. “CD ripping” now feasible.•1999: Shawn Fanning develops Napster, believing he has “bypassed” copyright law. Napster has >25M users in its first year.•Dec., 1999: RIAA sues Napster for “contributory and vicarious” copyright infringement.•April, 2000: Metallica sues Napster, Yale, Indiana Univ., and USC. (Yale bans the use of Napster within a week.)Napster History, continued•July, 2000: US District Judge Patel grants RIAA’s request for an injunction. The injunction is temporarily stayed soon thereafter.•October, 2000: Napster announces a partnership with Bertlesmann AG (one of the “major labels” in the industry whose trade association is suing it!).•January, 2001: Napster and Bertlesmann say that they will roll out a “subscription service” by “early summer” and will use “DRM technology.”Napster History, continued•February, 2001: Ninth Circuit upholds lower court’s findings that Napster is guilty of contributory and vicarious infringement.•Summer, 2001: Napster and Bertlesmann fail to roll out subscription service.•September, 2001: Napster reaches a settlement with music publishers (but not with RIAA record labels). However, CNET.com reports the number of users has “dropped from tens of millions…to almost zero.”? Napster, R.I.P. ?Gnutella P2P File Sharing•“Pure Peer-to-Peer.”•Peers are called “servents.”•Servents communicate over standard HTTP.•Goal is “total decentralization.” In particular, no Napster-like server that “directs traffic,” collects data, and otherwise centralizes control.“A” Generates a Gnutella Request•Creates–Search String S–(Unique) Request ID N–Time-to-Live T•Sends (A, S, N, T) to all of its Gnutella neighbors.“B” Receives Gnutella Request (A, S, N, T) •If B has already received request N or T=0, B drops this request and does nothing.• B looks up S in its local file system and sends (N, Result) to A.• B sends (B, S, N, T-1) to all of its Gnutella neighbors, and it records the fact that A has made the request N.•When B receives a response of the form (N, Result) from one of its neighbors, it forwards this response to A.Gnutella Advantages and DisadvantagesMain Advantage : “Search for S” can be done in many ways, e.g., structured database search, simple text matching, “fuzzy” text matching, etc. “Result” can take many forms.Main Disadvantage : Inefficiency!–“Flood” of Requests. If average number of neighbors is C and average TTL is D, each search can cause CD request messages.–Natural evolution into many barely-connected subnets, not one “user community.”Other Disadvantage : Request monitoring. (Comes with standard HTTP.)...Gnutella History•Gnutella was written by Justin Frankel, the 21-year-old founder of Nullsoft.•Nullsoft posted Gnutella on the Web, March 1999.•Nullsoft acquired by AOL, June 1999. •A day later AOL yanked Gnutella, at the bequest of Time Warner.•People had already downloaded and shared the program.•Gnutella continues today, run by independent programmers.Freenet P2P File Sharing•Works similarly to Gnutella. Exceptions include:–Intermediaries store all results. (Diffuses responsibility.)–Uses proprietary protocol. (Eliminates HTTP monitorability.)•Launched by Ian Clarke (Univ.of Edinburgh) in 1997.•Explicitly anti-censorship, anti-copyright, and pro-anonymity in its goals.RealNetworks: An Internet Media Delivery Solution•Full Name: RealNetworks, Inc.•Employees: 1,000•Stock Price (RNWK):–$5.04 (at close 10/2/01)–52-week range: $3.26 to $42•Earnings Per Share: -$0.68•Provides client and server software for streaming multimedia content over the Internet.RealNetworks Overview•Founded by Rob Glaser (as Progressive Networks) in 2/1994.•Acquired Vivo Software in 3/1998, Xing Technology in 8/1999, and Netzip, Inc. in 1/2000.•Went public in 11/1997; reached an all-time high (adjusted) price of $93/share in 2/2000.•Over 200 million registered users as of 6/2001; RealPlayer is installed on 95% of home PCs.RealNetworks Stock ChartRealNetworks Quarterly RevenuesRealNetworks Business Model•The basic RealPlayer software is free. Users may pay a small fee (~$20) for an advanced version with more features. Roughly 13% of the RealNetworks revenue stream comes from this.•Roughly 35% of its revenue stream is from services and advertising.•Roughly 50% of its revenue stream is from charging broadcasters of streaming data for the RealServer software.•In summary, the
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