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- Genre: Masters Thesis
Description
Voice and other circuit switched services in a LTE deployment can be based on a Circuit Switched Fall Back mechanism or on the upcoming Voice Over LTE option. Voice Over LTE option can be used with its SIP based signaling to route voice calls and other circuit switched services over the LTE's packet switched core. The main issue that is faced though is the validation of this approach before the deployment over commercial network. The test strategy devised as a result of this work will be able to visit corner scenarios and error sensitive services, so that signaling involved can be verified to ensure a robust deployment of the Voice Over LTE network. Signaling test strategy is based on the observations made during a simulated Voice Over LTE call inside the lab in a controlled environment. Emergency services offered are carefully studied to devise a robust test strategy to make sure that any service failure is avoided. Other area were the service is routed via different protocol stack layer than it normally is in a legacy circuit switched core are identified and brought into the scope of the test strategy.
ContributorsThotton Veettil, Vinayak (Author) / Reisslein, Martin (Thesis advisor) / Ying, Lei (Committee member) / McGarry, Michael (Committee member) / Arizona State University (Publisher)
Created2014
Description
New OpenFlow switches support a wide range of network applications, such as firewalls, load balancers, routers, and traffic monitoring. While ternary content addressable memory (TCAM) allows switches to process packets at high speed based on multiple header fields, today's commodity switches support just thousands to tens of thousands of forwarding rules. To allow for finer-grained policies on this hardware, efficient ways to support the abstraction of a switch are needed with arbitrarily large rule tables. To do so, a hardware-software hybrid switch is designed that relies on rule caching to provide large rule tables at low cost. Unlike traditional caching solutions, neither individual rules are cached (to respect rule dependencies) nor compressed (to preserve the per-rule traffic counts). Instead long dependency chains are ``spliced'' to cache smaller groups of rules while preserving the semantics of the network policy. The proposed hybrid switch design satisfies three criteria: (1) responsiveness, to allow rapid changes to the cache with minimal effect on traffic throughput; (2) transparency, to faithfully support native OpenFlow semantics; (3) correctness, to cache rules while preserving the semantics of the original policy. The evaluation of the hybrid switch on large rule tables suggest that it can effectively expose the benefits of both hardware and software switches to the controller and to applications running on top of it.
ContributorsAlipourfard, Omid (Author) / Syrotiuk, Violet R. (Thesis advisor) / Richa, Andréa W. (Committee member) / Xue, Guoliang (Committee member) / Arizona State University (Publisher)
Created2014