Shreyasee Mukherjee

EdgeBuffer: Caching and prefetching content at the edge in the MobilityFirst future Internet architecture

The prevalence of mobile devices especially smartphones has attracted research on mobile content delivery techniques. In this paper, we propose to take advantage of the storage available at wireless access points to bring content closer to mobile devices, hence improving the downloading performance. Specifically, we propose to have a separate popularity based cache and a prefetch buffer at the network edge to capture both long-term and short-term content access patterns. Further, we point out that it is insufficient to rely on a devices past history to predict when and where to prefetch, especially in urban settings; instead, we propose to derive a prediction model based on the aggregated network-level statistics. We discuss the proposed mobile content caching/prefetching method in the context of the MobilityFirst future Internet architecture. In MobilityFirst, when mobile clients move between network attachment points (e.g., Wi-Fi access points), their network association records are logged by the network, which then naturally facilitates the network-level mobility prediction. Through detailed simulations with real taxi mobility traces, we show that such a strategy is more effective than earlier schemes in satisfying content requests at the edge (higher cache hit ratios), leading to shorter content download latencies. Specifically, the fraction of requests satisfied at the edge increases by a factor of 2.9 compared to a caching only approach, and by 45% compared to individual user-based prediction and prefetching.

Enabling vehicular networking in the MobilityFirst future internet architecture

Vehicular networking, both vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I), is an increasingly important usage scenario for future mobile Internet services. Radio technologies such as 3G/4G and WAVE/802.11p now enable vehicles to communicate with each other and connect to the Internet, but there is still the lack of a unifying network protocol architecture for delivery of services across both V2V and V2I modes. The MobilityFirst future Internet architecture, discussed in this paper, is a clean-slate protocol design in which the requirements of untethered nodes and dynamically formed networks are considered from the ground-up, making it particularly suitable for vehicular applications. Here we describe the vehicular networking specific features and protocol design details of the architecture and present evaluation results on performance and scalability.

Achieving Scalable Push Multicast Services Using Global Name Resolution

This paper presents a novel approach to achieving scalable push multicast services using the distributed global name resolution service associated with emerging name-based network architectures. The proposed named-object multicast (NOMA) scheme employs unique names to identify multicast groups while using the global name resolution service (GNRS) to store the tree structure and maintain current mappings to mobile end-user addresses. The NOMA scheme achieves improved scalability and performance over conventional multicast protocols such as PIM-SM and MDSP by taking advantage of the GNRS to simplify tree management and limit control overhead. Performance evaluation results including comparisons with IP multicast are given using a combination of analysis and NS-3 simulation. The results show good scalability properties along with low control overhead for medium to large multicast groups. In addition, NOMA seamlessly handles mobility for end-hosts subscribed to a group, avoiding data losses upon mobility events. Results further demonstrate how separating names from addresses enables NOMA to dynamically forward traffic to mobile users. In conclusion, we describe a proof-of-concept prototype developed for further experimental validation of the proposed NOMA multicast routing scheme.

Network-assisted multihoming for emerging heterogeneous wireless access scenarios

This paper presents a technique for enabling multihoming in the emerging heterogeneous (“hetnet”) mobile wireless access scenarios, where mobile devices have dual wireless interfaces (such as Wi-Fi and LTE) and can use either or both to achieve significant improvements in performance and service quality. A novel network-assisted technique for multihoming is introduced, enabled by the globally unique identifier (GUID) based routing in the proposed MobilityFirst Future Internet architecture, now under development. In particular, the approach shifts the burden of policy expression and data-striping from end-nodes to in-network nodes, and utilizes named object routing with GUIDs to establish multiple paths to destination mobile devices. The proposed multihoming technique uses hop-by-hop backpressure for data striping at the bifurcation router and includes a robust mechanism to reduce reordering of packets at the receive buffer. We quantify the performance gains using detailed NS3 based simulations and present results from a thorough parametric study to determine the effects of datarate, delay and hop-count difference between multiple available paths. We also show that when multiple interfaces are available, simultaneous use of both the interfaces is beneficial only under certain conditions depending on the ratio of the data-rate of the interfaces and the size of the flow.

EIR: Edge-aware inter-domain routing protocol for the future mobile internet

Abstract This work describes a clean-slate inter-domain routing protocol designed to meet the needs of the future mobile Internet. In particular, we describe the edge-aware inter-domain routing (EIR) protocol which provides new abstractions, such as aggregated-nodes (aNodes) and virtual-links (vLinks) for expressing network topologies and edge network properties necessary to address mobility related routing scenarios which are inadequately supported by the border gateway protocol (BGP) in use today. Specific use-cases addressed by EIR include emerging mobility service scenarios such as multi-homing across WiFi and cellular, multipath routing over several access networks, and anycast access from mobile devices to replicated cloud services. It is shown that EIR can be used to realize efficient routing strategies for the mobility use-cases under consideration, while also providing support for a range of inter-domain routing policies currently associated with BGP. Simulation results for protocol overhead are presented for a global-scale CAIDA topology, leading to an identification of parameters necessary to obtain a good balance between overhead and routing table convergence time. A Click-based proof-of-concept implementation of EIR on the ORBIT testbed is described and used to validate performance and functionality for selected mobility use-cases, including mobile data services with open WiFi access points and mobile platforms such as buses operating in an urban area.

Inter-domain routing with cut-through switching for the MobilityFirst Future Internet architecture

Future Internet projects such as MobilityFirst and Named Data Networking have proposed novel mechanisms to replace the Internet Protocol to better support content delivery and mobility. However, the problem of efficient data transfer across the network core has not been adequately investigated. We tackle the challenge of inter-domain cut-through switching using software-defined networking (SDN). First, we propose and solve an optimization problem that minimizes the total transfer time using inter-domain tunnels. Second, we propose an SDN-based routing framework for the MobilityFirst architecture capable of dynamically creating such tunnels. The main novelty of this framework is to name tunnels as network objects to simplify how tunnels are created and maintained. To validate our framework, we implement on the GENI (Global Environment for Network Innovations) testbed a prototype for the MobilityFirst architecture. Our experiments with the optimization problem show that the inter-domain latency between controllers plays a key role on how tunnels are setup. Furthermore, our implementation experiments show that the control plane delay can be reduced by 75% when using inter-domain tunnels. Finally, we show how our framework needs fewer messages than current protocols such as label distribution protocol (LDP) to setup intra-domain and inter-domain tunnels.

Evaluating opportunistic delivery of large content with TCP over WiFi in I2V communication

With the increasing interest in connected vehicles, it is useful to evaluate the capability of delivering large content over a WiFi infrastructure to vehicles. The throughput achieved over WiFi channels can be highly variable and also rapidly degrades as the distance from the access point increases. While this behavior is well understood at the data link layer, the interactions across the various protocol layers (data link and up through the transport layer) and the effect of mobility may reduce the amount of content transferred to the vehicle, as it travels along the roadway. This paper examines the throughput achieved at the TCP layer over a carefully designed outdoor WiFi environment and the interactions across the layers that impact the performance achieved, as a function of the receiver mobility. The experimental studies conducted reveal that impairments over the WiFi link (frame loss, ARQ and increased delay) and the residual loss seen by TCP causes a cascade of duplicate ACKs to be generated. This triggers large congestion window reductions at the sender, leading to a drastic degradation of throughput to the vehicular client. To ensure outdoor WiFi infrastructures have the potential to sustain reasonable downlink throughput for drive-by vehicles, we speculate that there is a need to adapt how WiFi and TCP (as well as mobility protocols) function for such vehicular applications.

Edge-aware inter-domain routing for realizing next-generation mobility services

This work describes a clean-slate inter-domain routing protocol designed to meet the needs of the future mobile Internet. In particular, we describe the edge-aware inter-domain routing (EIR) protocol which provides new abstractions of aggregated-nodes (aNodes) and virtual-links (vLinks) for expressing network topologies and edge network properties necessary to address next-generation mobility related routing scenarios which are inadequately supported by the border gateway protocol (BGP) in use today. Specific use-cases addressed by EIR include emerging mobility service scenarios such as multi-homing across WiFi and cellular, multipath routing over several access networks, and anycast access from mobile devices to replicated cloud services. Simulation results for protocol overhead are presented for a global-scale Caida topology, leading to an identification of parameters necessary to obtain a good balance between overhead and routing table convergence time. A Click-based proof-of-concept implementation of EIR on the ORBIT testbed is described and used to validate performance and functionality for selected mobility use-cases, including mobile data services with open WiFi access points and mobile platforms such as buses operating in an urban area.

Integrating advanced mobility services into the future Internet Architecture

This paper discusses the design challenges associated with supporting advanced mobility services in the future Internet. The recent transition of the Internet from the fixed host-server model to one in which mobile platforms are the norm motivates a next-generation protocol architecture which provides integrated and efficient support for advanced mobility services. Key wireless access and mobility usage scenarios are identified including host mobility, multihoming, vehicular access and context addressability, and key protocol support requirements are identified in each case. The MobilityFirst (MF) architecture being developed under the National Science Foundations future Internet Architecture (FIA) program is proposed as a possible realization that meets the identified requirements. MF protocol specifics are given for each wireless/mobile use case, along with sample evaluation results demonstrating achievable performance benefits.