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Inter-Domain Traffic Engineering using the Origin Preference Attribute
No full textBook description: An ever-increasing thirst for information in recent years among consumers, researchers, and the general population has necessitated continuous growth of internet architecture and accessibility, an issue which, if not addressed properly, may inhibit the growth of the internet as a whole.
Solutions for Sustaining Scalability in Internet Growth investigates current issues impeding the growth of information architecture and explores methods for developing a wider-reaching and ever-evolving internet. The book presents viable solutions to some of the current threats to robust and pervasive information systems, enabling internet actors such as network providers, service providers, vendors, and regulatory bodies to ensure the creation of a more accessible and balanced internet.Inter-domain Traffic Engineering (TE) is an important aspect of network operation both technically and economically. Outbound Traffic Engineering is less problematic as routers under the control of the network operator are responsible for the way traffic leaves the network. The inbound direction is considerably harder as the way traffic enters a network is based on routing decisions in other networks. There are very few mechanisms available today that facilitate inter-domain inbound traffic engineering, such as prefix deaggregation (i.e., advertise more specific prefixes), AS path prepending and systems based on BGP communities. These mechanisms have severe drawbacks such as exacerbating the increase of the size of global routing table or providing only coarse-grained control. In this chapter, an alternative mechanism is described and evaluated. The proposed solution does not increase the size of the global routing table, is easy to configure through a simple numeric value and provides a finer-grained control compared to currently used mechanisms that also do not add additional prefixes to the global routing table.TRUEpu
BASICS: Scheduling Base Stations to Mitigate Interferences in Cellular Networks
Get PDFThe increasing demand for higher data rates in cellular network results in increasing network density. As a consequence, inter-cell interference is becoming the most serious obstacle towards spectral efficiency. Therefore, considering that radio resources are limited and expensive, new techniques are required for efficient radio resource allocation in next generation cellular networks. In this paper, we propose a pure frequency reuse 1 scheme based on base station scheduling rather than the commonly adopted user scheduling. In particular, we formulate a base station scheduling problem to determine which base stations can be scheduled to simultaneously transmit, without causing excessive interference to any user of any of the scheduled base stations. We show that finding the optimal base station scheduling is NP-hard, and formulate the BASICS (BAse Station Inter-Cell Scheduling) algorithm, a novel heuristic to approximate the optimal solution at low complexity cost. The proposed algorithm is in line with the ABSF (almost blank sub-frame) technique recently standardized at the 3GPP. By means of numerical and packet-level simulations, we prove the effectiveness and superiority of BASICS as compared to the state of the art of inter-cell interference mitigation schemes.TRUEpu
A Model to Quantify the Success of a Sybil Attack Targeting RELOAD/Chord Resources
Get PDFThe Sybil attack is one of the most harmful security threats for distributed hash tables (DHTs). This attack is not only a theoretical one, but it has been spotted "in the wild", and even performed by researchers themselves to demonstrate its feasibility. In this letter we analyse the Sybil attack whose objective is that the targeted resource cannot be accessed by any user of a Chord DHT, by replacing all the replica nodes that store it with sybils. In particular, we propose a simple, yet complete model that provides the number of random node-IDs that an attacker would need to generate in order to succeed with certain probability. Therefore, our model enables to quantify the cost of performing a Sybil resource attack on RELOAD/Chord DHTs more accurately than previous works, and thus establishes the basis to measure the effectiveness of different solutions proposed in the literature to prevent or mitigate Sybil attacks.pu
OF.CPP: Consistent Packet Processing for OpenFlow
Get PDFThis paper demonstrates a new class of bugs that is likely
to occur in enterprise OpenFlow deployments. In particular, step-by-step, reactive establishment of paths can cause
network-wide inconsistencies or performance- and space-
related inefficiencies. The cause for this behavior is inconsistent packet processing: as the packets travel through the network they do not encounter consistent state at the Open-Flow controller. To mitigate this problem, we propose to use transactional semantics at the controller to achieve consistent packet processing. We detail the challenges in achieving this goal (including the inability to directly apply database techniques), as well as a potentially promising approach. In particular, we envision the use of multi-commit transactions that could provide the necessary serialization and isolation properties without excessively reducing network performance.TRUEpu
Network-based Distributed Mobility (DMM) Demo
No full textDemo (MEDIEVAL - Multimedia Transport for Mobile Video Applications - project).FALSEpu
RIA-ICCS: Intercell Coordinated Scheduling Exploiting Application Reservation Information
Get PDFIntercell coordination and cooperation techniques are some of the most promising approaches to increase the spectral efficiency of future wireless systems as required by the forecasted market needs. Among them, intercell coordinated scheduling (ICCS) arises as a near-term feasible solution due to its lower inter-BS communication requirements when compared to full cooperative approaches. In this paper we present our proposed Reservation Information Aware Intercell Coordinated Scheduling (RIA-ICCS) solution which considers application reservation information when constructing an interference graph for ICCS purposes.
Our results shows that i) RIA-ICCS allows to significantly reduce the number of edges in an interference graph for ICCS solutions and its benefit increases as the number of mobile stations grows, i.e., when the system needs it most and ii) the reduced number of edges in the interference graph can be effectively translated to a lower blocking probability using stateof-the-art resource allocation algorithms.TRUEpu
The Aftermath of Prefix Deaggregation
Get PDFPrefix deaggregation is recognized as a steady long-
lived phenomenon at the interdomain level, despite its well-known negative effects for the community. The advertisement of more-specific prefixes provides network operators with a fine-grained method to control the interdomain ingress traffic. Moreover, customer networks combining this mechanism with selective advertisements may decrease their monthly transit traffic bill and potentially impact the business of their providers.
In this paper, we develop a methodology for Internet Service
Providers (ISPs) to monitor new occurrences of prefix deaggregation within their customer base. Moreover, the ISPs can detect on their own when deaggregation may decrease the transit bill of their customer networks. We first examine the ISP’s BGP routing data for new cases of prefix deaggregation generated by customers. Then, we check for selective advertisements of the newly generated prefixes using external routing data. We look beyond the incentives for deploying this type of strategy and instead we examine its economic impact. We exemplify the proposed methodology on a complete set of data including routing, traffic, topological and billing information provided by a major Japanese ISP and we discuss the implications of the obtained results.TRUEpu
IXP traffic: a macroscopic view
Get PDFToday's public Internet eXchange Points (IXP) are a crucial element in the Internet ecosystem, carrying around 20--24Tbps, i.e. 15-20% of Internet's inter-domain traffic and supporting a large percentage of links among autonomous systems. In spite of their importance, community still lacks empirical data on the nature of the traffic exchanged through IXPs. In this paper, we analyze the traffic data from two medium-size IXPs and draw several important conclusions. We quantify the relationship between the different types (access/content/transit) of ISPs present in the two studied IXPs, both in terms of traffic volumes and peering intensity. We also demonstrate that the peering (AS-level) topology within the IXP is impacted by the pricing model of the IXP. Finally, we shed light on the temporal characteristics of the traffic exchanged at IXPs and list a number of research problems that can benefit from the data studied here. We strongly believe that, in contrast with confidential datasets typically used in studying the Internet traffic characteristics, the IXP data provide rich and publicly available resources crucial for understanding various aspects of the Internet.TRUEpu