Zhongxing Ming Javier Ubillos Mingwei Xu Tsinghua University

FQDN resolution and IP management is dealt with by the application All cool stuff have to be implemented by the application. Mobility Multi-homing IPv4/IPv6 agnosticism NA(P)T traversal Path diversity exploitation Etc… addr = gethostbyname (someString ); …… connect( …, addr, … ); write( … ); close( … ); connect (…, addr, …); write( … ); colse( … ); Tsinghua University

Developers seem to like them… One implementation for every framework More often than not Resolve once Resue IP …… Tsinghua University

Provide the socket abstraction developers like. Do allow all the cool functions of surrogate addresses But dont introduce new indirections And be explicit about that it is different Tsinghua University

Tsinghua University 5 New API Not binary compatible A session layer Easy transition Minor changes or none Compatible Middle-boxes unaffected Network Host

Tsinghua University 6 Application Transport Network Outside the host Name-based sockets HIP LISP SCTP

listen() – Prep for incoming session Fd = listen(src_name, dst_name, local_port, transport); open() – Initiate outgoing sesion Fd = open(src_name, dst_name, remote_port, transport); accept() – Receive incoming session (src_name, dst_name, fd) = accept(fd); read() – Receive data Data = read(fd); write() – Send data Write(fd, data); close() – Close session Close(fd); Tsinghua University

It has been a long struggle to manage mobility in todays IP networks. NBS allows mobile device users to move from one network to another while maintaining the connection. DNS and Shim6 is involved to support mobile NBS No triangular routing Fast handover Good reliability Tsinghua University

src_namedst_name src_ipdst_ip src_namedst_name hash(src_name)hash(dst_name) hash(src_name)hash(dst_name) src_locdst_loc NBS Shim6 Before shim6 state establishment After shim6 state establishment Tsinghua University

Original Shim6 State Machine Modified Shim6 State Machine Tsinghua University

DNS DNS AR 3 AR 1 AR 2 Mobile Node (A) Name: IP: Mobile Node (A) Name: IP: Correspondent Host (B) Name: host.com IP: Tsinghua University

DNS AR4 AR1 AR2 AR3 A B Tsinghua University

Tsinghua University

Handover time for different IEEE b cards Tsinghua University Throughput graph during movement

Bernhard Age et al studies various DNS resolvers around the world and found that there are only less than 1\% of the cases for which DNS resolvers take more that 100ms to answer Concurrent move is not very likely to occur Thus DNS delay wont be a problem in practice Tsinghua University

Propose and implement name-based sockets as a socket-API abstraction so that an application developer may use names instead of IP-addresses. improve Shim6 and integrate it with name- based sockets to provide mobility functionality. Evaluate the performance of the proposed mechanism using a real testbed Tsinghua University

Questions? Tsinghua University