128 research outputs found
A Protocol for Scalable Application Layer Multicast
We describe a new application-layer multicast protocol that is
specifically
designed to scale to large groups.
Our scheme is based upon a hierarchical clustering of the
application-layer multicast peers and can be used to produce a number
of different data delivery trees with specific properties. On
average, group members using our protocol maintain only a constant
amount of state about other group members, and incur a constant amount
of control overhead.
We present extensive simulations of both our protocol and the Narada
protocol over Internet-like topologies. Our results show that for
groups of size 32 or more, we reduce control overhead by orders of
magnitude, and link stress by 25%, while retaining similar
end-to-end latencies and failure recovery properties
Poor Man's Content Centric Networking (with TCP)
A number of different architectures have been proposed in support of data-oriented or information-centric networking. Besides a similar visions, they share the need for designing a new networking architecture. We present an incrementally deployable approach to content-centric networking based upon TCP. Content-aware senders cooperate with probabilistically operating routers for scalable content delivery (to unmodified clients), effectively supporting opportunistic caching for time-shifted access as well as de-facto synchronous multicast delivery. Our approach is application protocol-independent and provides support beyond HTTP caching or managed CDNs. We present our protocol design along with a Linux-based implementation and some initial feasibility checks
Flexible Application-Layer Multicast in Heterogeneous Networks
This work develops a set of peer-to-peer-based protocols and extensions in order to provide Internet-wide group communication. The focus is put to the question how different access technologies can be integrated in order to face the growing traffic load problem. Thereby, protocols are developed that allow autonomous adaptation to the current network situation on the one hand and the integration of WiFi domains where applicable on the other hand
Multicast in DKS(N, k, f) Overlay Networks
Recent developments in the area of peer-to-peer computing show that structured overlay networks implementing distributed hash tables scale well and can serve as infrastructures for Internet scale applications. We are developing a family of infrastructures, DKS(N; k; f), for the construction of peer-to-peer applications. An instance of DKS(N; k; f) is an overlay network that implements a distributed hash table and which has a number of desirable properties: low cost of communication, scalability, logarithmic lookup length, fault-tolerance and strong guarantees of locating any data item that was inserted in the system. In this paper, we show how multicast is achieved in DKS(N, k, f) overlay networks. The design presented here is attractive in three main respects. First, members of a multicast group self-organize in an instance of DKS(N, k, f) in a way that allows co-existence of groups of different sizes, degree of fault-tolerance, and maintenance cost, thereby, providing flexibility. Second, each member of a group can multicast, rather than having single source multicast. Third, within a group, dissemination of a multicast message is optimal under normal system operation in the sense that there are no redundant messages despite the presence of outdated routing information
DCCast: Efficient Point to Multipoint Transfers Across Datacenters
Using multiple datacenters allows for higher availability, load balancing and
reduced latency to customers of cloud services. To distribute multiple copies
of data, cloud providers depend on inter-datacenter WANs that ought to be used
efficiently considering their limited capacity and the ever-increasing data
demands. In this paper, we focus on applications that transfer objects from one
datacenter to several datacenters over dedicated inter-datacenter networks. We
present DCCast, a centralized Point to Multi-Point (P2MP) algorithm that uses
forwarding trees to efficiently deliver an object from a source datacenter to
required destination datacenters. With low computational overhead, DCCast
selects forwarding trees that minimize bandwidth usage and balance load across
all links. With simulation experiments on Google's GScale network, we show that
DCCast can reduce total bandwidth usage and tail Transfer Completion Times
(TCT) by up to compared to delivering the same objects via independent
point-to-point (P2P) transfers.Comment: 9th USENIX Workshop on Hot Topics in Cloud Computing,
https://www.usenix.org/conference/hotcloud17/program/presentation/noormohammadpou
On the Cost of Participating in a Peer-to-Peer Network
In this paper, we model the cost incurred by each peer participating in a
peer-to-peer network. Such a cost model allows to gauge potential disincentives
for peers to collaborate, and provides a measure of the ``total cost'' of a
network, which is a possible benchmark to distinguish between proposals. We
characterize the cost imposed on a node as a function of the experienced load
and the node connectivity, and show how our model applies to a few proposed
routing geometries for distributed hash tables (DHTs). We further outline a
number of open questions this research has raised.Comment: 17 pages, 4 figures. Short version to be published in the Proceedings
of the Third International Workshop on Peer-to-Peer Systems (IPTPS'04). San
Diego, CA. February 200
Applying Prolog to Develop Distributed Systems
Development of distributed systems is a difficult task. Declarative
programming techniques hold a promising potential for effectively supporting
programmer in this challenge. While Datalog-based languages have been actively
explored for programming distributed systems, Prolog received relatively little
attention in this application area so far. In this paper we present a
Prolog-based programming system, called DAHL, for the declarative development
of distributed systems. DAHL extends Prolog with an event-driven control
mechanism and built-in networking procedures. Our experimental evaluation using
a distributed hash-table data structure, a protocol for achieving Byzantine
fault tolerance, and a distributed software model checker - all implemented in
DAHL - indicates the viability of the approach
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