Question: Victor Garber plays the role of Dr. Martin Stein on the web series on what streaming platform?

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Unified Streaming: Unified Streaming provides software for streaming, offline packaging and recording of streaming video and audio.  Unified Streaming platform aims to deliver a single source to various formats, avoiding the need for separate infrastructure.  It fits into existing web servers (Apache, IIS, Nginx and Lighttpd) and runs on Windows, Linux and Unix.

IROKO Partners: iROKO Partners is an online media distribution company focused on the Nigerian Entertainment Industry.  The company was established in September 2010 and is headquartered in Lagos, with a branch in London, United Kingdom.  The company is led by its co-founders Jason Njoku (CEO) and Bastian Gotter along with major investor Nazar Yasin.  iROKO Partners offers a range of online media products including its movie streaming website named iROKOtv focused on Nollywood Film productions, and 'iROKING', a Nigerian music streaming platform.  Other web brands are iROKtv, NollywoodLove and YorubaLove which operate on the YouTube video platform.

Arrowverse: The Arrowverse is a shared fictional universe that is centered on television series airing on The CW, developed by Greg Berlanti, Marc Guggenheim, Andrew Kreisberg, Phil Klemmer, and Geoff Johns, based on characters appearing in publications by DC Comics.  The shared universe, much like the DC Universe in comic books or the cinematic DC Extended Universe, was established by crossing over common plot elements, settings, cast, and characters.  The Arrowverse stars Stephen Amell as Oliver Queen / Green Arrow, Grant Gustin as Barry Allen / Flash, Megalyn Echikunwoke as Mari Jiwe McCabe / Vixen, with an ensemble cast leading "Legends of Tomorrow", including Arthur Darvill as Rip Hunter, Caity Lotz as Sara Lance / White Canary, Brandon Routh as Ray Palmer / Atom, Dominic Purcell as Mick Rory / Heat Wave, with Victor Garber and Franz Drameh as Martin Stein & Jefferson "Jax" Jackson / Firestorm.  Russell Tovey stars as Ray Terrill / The Ray.

Vixen (web series): Vixen is an American animated web series from executive producers Greg Berlanti, Marc Guggenheim and Andrew Kreisberg, which debuted on August 25, 2015, on The CW's online streaming platform, CW Seed.  It is based on the DC Comics character Mari McCabe / Vixen, a costumed superhero crime-fighter with the power to mimic the abilities of any animal that has ever lived on Earth.  The series is set in the Arrowverse, the same fictional universe as "Arrow", "The Flash", and "Legends of Tomorrow".  In January 2016, the series was renewed for a second season, which premiered on October 13, 2016.

Victor Garber: Victor Joseph Garber (born March 16, 1949) is a Canadian actor and singer.  He is known for playing Jesus in "Godspell", Anthony Hope in "", John Wilkes Booth in "Assassins", Jack Bristow in the television series "Alias", Max in "Lend Me a Tenor", Thomas Andrews in James Cameron's "Titanic", and Ken Taylor, Canadian Ambassador to Iran, in "Argo".  He is currently a series regular on "Legends of Tomorrow" as Dr. Martin Stein, playing the same role as a guest star on "The Flash" and the web series "Vixen.

Platform envelopment: Platform envelopment refers to one platform provider moving into another one's market, combining its own functionality with the target's, to form a multi-platform bundle.  The markets which evolve rapidly are rich in enveloping opportunities and the companies in these markets are under the continuous threat of becoming obsolete.  Mobile phones used to be a separate market but the boundaries between them and music players are beginning to blur.  A stand-alone business when threatened with an envelopment attack has few options but to change the business model or sell off the business to the attacker.  RealPlayer was a dominant player in the streaming video business and had created a two sided market out of which the consumers were the subsidized side.  The content providers were the money side which paid Real for their streaming software.  Microsoft launched an envelopment attack on Real by providing the streaming server software clubbed with their Windows NT operating system.  The content providers saw no point in continuing using Real and moved to windows platform threatening the existence of Real.  Windows could afford to do so since the provision of such a service boosted their sales of the OS and the mass adoption of the Windows Media Player on the consumer side which was the only compatible player with the windows streaming platform.

JoJoHead: JoJoHead is a 2016 American comedy web series written and created by Johanna Stein, which debuted on October 14, 2016, on The CW's online streaming platform, CW Seed.  It stars creator Johanna Stein as JoJo and features numerous guest stars over 18 episodes.  The series is directed by Stein's producing partner, Suzanne Luna.

Electra Woman and Dyna Girl (web series): Electra Woman and Dyna Girl (stylized as Electra Woman & Dyna Girl) is an 2016 American superhero comedy web series that is a reboot of the 1976 television series of the same name.  The series stars YouTube personalities, Grace Helbig and Hannah Hart as Electra Woman and Dyna Girl, respectively.  The series was digitally released by Fullscreen through its own streaming platform in eight 11-minute web episodes, on April 26, 2016, and was released on all major platforms on June 7, 2016, by Legendary Digital Studios and Sony Pictures Home Entertainment.  The series centers around the superhero duo as they fight crime in their local Akron, Ohio, before relocating to Los Angeles.

Jack Bristow: Jonathan "Jack" Donahue Bristow, played by Victor Garber, is Sydney Bristow's father on the television series "Alias".  Victor Garber was thrice nominated for an Emmy Award for his portrayal of Jack, and fans voted the relationship between Sydney and Jack the best non-romantic relationship on the show in the 2005 AllAlias.com Fans' Choice Awards.

Freedom Fighters: The Ray: Freedom Fighters: The Ray is an upcoming American animated web series developed by Greg Berlanti and Marc Guggenheim.  It will debut in 2017 on The CW's online streaming platform, CW Seed and is based on DC Comics character Ray Terrill / The Ray, a reporter who gains light-based powers after being exposed to a genetic light bomb.  The series is set in the Arrowverse, the same fictional universe as "Arrow", "The Flash", and "Legends of Tomorrow", while also taking place on the alternate earth, Earth-X.

Supporting paragraphs: Victor Garber Vixen (web series)
Answer: CW Seed