Evaluating the Perfomance of the Modified Dynamic Hose Model for Virtual Private Networks

This paper is designed to model a Modified Dynamic Hose Algorithm for data traffic management. The Virtual Private Network (VPN) under study was characterized and the data for transmission was modeled. Then Algorithm for Modified Dynamic Hose Model to handle varying traffic rates was developed and simulated using MATLAB. The results obtained from network characterization shows that variation in window size and packet size affects the throughput in a VPN as an increase in window size from 50kb to 100kb improved the throughput generated from 15 for the Conventional Hose Model to 28.3 for the Modified Dynamic Hose Model resulting in 13.3 throughputs, which translate to 47% improvement. Also variation in window size and packet size affects the throughput in a VPN as an increase in window size from 10kb to 50kb resulted to a maximum throughput of 3.01 for the Conventional Model as against 15 for the Modified Dynamic Hose Model resulting to additional 11.99 or improvement of 79.93%. The Modified Dynamic Hose Model algorithm, unlike the Conventional Hose Model, determines whether to drop a particular packet or to queue it thereby improving the bandwidth utilization, minimize latency (delays) and Virtual Private Network Throughput

Enabling Work-conserving Bandwidth Guarantees for Multi-tenant Datacenters via Dynamic Tenant-Queue Binding

Today's cloud networks are shared among many tenants. Bandwidth guarantees and work conservation are two key properties to ensure predictable performance for tenant applications and high network utilization for providers. Despite significant efforts, very little prior work can really achieve both properties simultaneously even some of them claimed so. In this paper, we present QShare, an in-network based solution to achieve bandwidth guarantees and work conservation simultaneously. QShare leverages weighted fair queuing on commodity switches to slice network bandwidth for tenants, and solves the challenge of queue scarcity through balanced tenant placement and dynamic tenant-queue binding. QShare is readily implementable with existing switching chips. We have implemented a QShare prototype and evaluated it via both testbed experiments and simulations. Our results show that QShare ensures bandwidth guarantees while driving network utilization to over 91% even under unpredictable traffic demands.Comment: The initial work is published in IEEE INFOCOM 201

Routing algorithm for provisioning symmetric virtual private networks in the hose model

A virtual private network (VPN) is a private data network where remote sites are connected over a shared provider network. In order to provide secure communications between customer sites, predetermined paths are used to forward data packets. To support quality of service (QoS), bandwidth has to be reserved on these paths. Then, finding appropriate paths in order to optimize the bandwidth used becomes an important problem. In this paper, we study the routing problem of VPNs under the hose model, where VPN endpoints specify the maximum bandwidth they need in sending and receiving data. Some previous works considered the problem under the assumption that all links have infinite capacities. We remove this constraint in our studies and develop enhancement to existing algorithms. Our simulation results show that our algorithm works very well in networks where link capacities are tight. © 2005 IEEE.published_or_final_versio

Energy Efficient Network Resource Allocation Scheme for Hose Model

Given the exponential growth in telecommunication networks, more and more attention is being paid to their energy consumption. However, the often over-provisioned　wired network is still overlooked. In core networks, pairs of routers are typically connected by multiple physical cables that form one logical bundled link participating in　the intra-domain routing protocol. To reduce the energy consumption of hose-model　networks with bundled cables, we propose a scheme to deactivate the maximum number　of cables, and associated equipment, possible. A similar approach has been presented　for the pipe model, where the exact traffic matrix is assumed to be known. Due to　traffic　uncertainty, however, it is difficult for operators to have exact knowledge of the　traffic matrix. This traffic uncertainty can be avoided by using the hose model, which　specifies only the upper bounds of the egress/ingress traffic from/to a node. We introduce a mixed integer linear problem formulation that yields the optimal solution and a more practical and near optimal heuristic algorithm for large networks. Our performance evaluation results show that it offers up to 50% power reduction compared to shortest path routing.電気通信大学201

Auto-bandwidth control in dynamically reconfigured hybrid-SDN MPLS networks

The proposition of this work is based on the steady evolution of bandwidth demanding technology, which currently and more so in future, requires operators to use expensive infrastructure capability smartly to maximise its use in a very competitive environment. In this thesis, a traffic engineering control loop is proposed that dynamically adjusts the bandwidth and route of flows of Multi-Protocol Label Switching (MPLS) tunnels in response to changes in traffic demand. Available bandwidth is shifted to where the demand is, and where the demand requirement has dropped, unused allocated bandwidth is returned to the network. An MPLS network enhanced with Software-defined Networking (SDN) features is implemented. The technology known as hybrid SDN combines the programmability features of SDN with the robust MPLS label switched path features along with traffic engineering enhancements introduced by routing protocols such as Border Gateway Patrol-Traffic Engineering (BGP-TE) and Open Shortest Path First-Traffic Engineering (OSPF-TE). The implemented mixed-integer linear programming formulation using the minimisation of maximum link utilisation and minimum link cost objective functions, combined with the programmability of the hybrid SDN network allows for source to destination demand fluctuations. A key driver to this research is the programmability of the MPLS network, enhanced by the contributions that the SDN controller technology introduced. The centralised view of the network provides the network state information needed to drive the mathematical modelling of the network. The path computation element further enables control of the label switched path's bandwidths, which is adjusted based on current demand and optimisation method used. The hose model is used to specify a range of traffic conditions. The most important benefit of the hose model is the flexibility that is allowed in how the traffic matrix can change if the aggregate traffic demand does not exceed the hose maximum bandwidth specification. To this end, reserved hose bandwidth can now be released to the core network to service demands from other sites