Rethinking data transport for a truly mobile world

Mobile devices such as smartphones and tablets are rapidly becoming the dominant mode of Internet access. Mobile and wireless networks are very different from the traditional Internet: mobility causes network addresses to change, mobile devices have access to multiple different networks, wireless network rates are highly variable, and delays on wireless networks are variable and often unacceptably high. These new realities cause current data transport protocols and the applications that rely on them to perform poorly (or not at all). This talk will describe Mosh and Sprout, two new protocols to overcome these problems. Mosh is a interactive terminal application for mobile networks, which has become a popular SSH replacement for mobile users since its release in April 2012. Sprout is a transmission control method for cellular wireless networks, a TCP replacement that delivers high throughput while bounding the end-to-end delay over cellular wireless networks. Sprout outperforms previous TCP variants as well as current videoconferencing protocols like Skype, Hangout, and Facetime over cellular networks. The talk will focus on the principles and practical considerations that went into the design of Mosh and Sprout. Mosh is joint work with Keith Winstein; Sprout is joint work with Keith Winstein and Anirudh Sivaraman (Keith and Anirudh are my PhD students).