The Experts below are selected from a list of 11688 Experts worldwide ranked by ideXlab platform
Zabih Ghassemlooy - One of the best experts on this subject based on the ideXlab platform.
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ultra fast all optical packet switched Routing with a hybrid header address correlation scheme
High Performance Switching and Routing, 2008Co-Authors: M F Chiang, Zabih Ghassemlooy, H L MinhAbstract:The paper presents a new node architecture for an all-optical packet router employing multiple pulse position modulation (PPM) Routing Table with a hybrid packet header correlation scheme. Most existing Routing Tables within a node contain a large number of entries, thus resulting in a long packet header address correlation time before delivering the incoming packet to its destination. In the proposed multiple PPM Routing Tables (PPRTs) the packet header address is based on the binary and PPM formats which leads to a much reduced Routing Table size. The packet header address correlation is carried out using only a single optical AND gate, thus offering reduced system complexity. It is also shown that the proposed scheme offers unicast/multi-cast/broadcast transmitting capabilities. The propose scheme is simulated and its characteristics are investigated. The output inter-channel crosstalk (CXT) of up to -18 dB and output packet power fluctuation of 2 dB have been achieved, which largely depend on the guard time between the arriving packets.
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all optical packet switched Routing based on pulse position modulated header
The 7th IASTED International Conferences on Wireless and Optical Communications (WOC 2007), 2007Co-Authors: Ming Feng Chiang, Zabih Ghassemlooy, H. L. MinhAbstract:The paper presents a node architecture for an all-optical packet router where packet header address and the Routing Table formats are based on the pulse position modulation (PPM). A single bit-wise AND gate is used for correlation of a packet header address with the PPM based Routing Table (PPRT) entries, thus resulting in reduced processing time and system complexity. It is also shown that the proposed scheme offer unicast/multi-cast/broadcast transmitting capabilities. We show that the optical power of the correlated packet header address and the switched signal on-off contrast ratio largely depend on the switching window width and the timing offset of the PPM header address.
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opn06 3 multiple hop Routing based on the pulse position modulation header processing scheme in all optical ultrafast packet switching network
Global Communications Conference, 2006Co-Authors: Le H Minh, Zabih GhassemlooyAbstract:In this paper we present modeling and simulation of multiple-hop all-optical packet Routing based on the pulse- position modulation header processing (PPM-HP) scheme in ultrafast optical packet switching network. Optical core node employing PPM-HP requires a dedicated Routing Table based on PPM scheme that will result in significantly reduced number of Routing Table entries. In this scheme, the header address correlation, using optical AND gates, is carried out by employing only a single bit-wise for each entry rather than a multiple-bit stream as in the existing systems thus resulting in reduced header processing time and avoiding the slow gain-recovery of AND gates. The reduced Routing Table also offers embedding multiple transmitting modes (unicast, multicast, broadcast) in optical layer and improves core network scalability where the number of core/edge nodes could be altered without the need for changing the number of Routing Table entries. The simulation results for the optical signal-to-noise ratio (OSNR) of packets at each hop are presented and compared with the theoretical calculations.
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Simulation of all-optical Routing employing PPM-based header processing in photonic packet switched core network
HUT-ICCE 2006 First International Conference on Communications and Electronics Proceedings, 2006Co-Authors: H. L. Minh, Zabih Ghassemlooy, Wai Pang NgAbstract:The paper presents the simulation in VPI of all-optical Routing based on the pulse-position modulation header processing (PPM-HP) scheme in an ultrafast photonic packet switched core network. In this network, optical core router employing PPM-HP utilizes a dedicated multi-wavelength pulse-position Routing Table (MW-PPRT) which results in a significant reduction of the number of Routing Table entries thus reducing the header processing time compared to the existing sequential Routing Table looking-up schemes. The reduced Routing Table also offers embedding multiple transmitting modes (unicast, multicast and broadcast) in an optical layer and improves scalability of the core network where the number of core/edge nodes could be altered without changing the number of Routing Table entries. Details of simulation schematics and results of the router operating at 100 Gbit/s are presented.
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All-Optical Packet Router Based on Multi-Wavelength PPM Header Processing
11th European Conference on Networks & Optical Communications (NOC 2006), 2006Co-Authors: Hoa Le Minh, Wai Pang Ng, Zabih Ghassemlooy, Ming Feng ChiangAbstract:The paper proposes an all-optical 1×M router architecture based on pulse-positionmodulation header processing (PPM-HP) scheme for packet Routing in all-optical highspeed wavelength division multiplexing (WDM) packet switching network. The router is mainly comprised of all-optical clock extraction, pulse-position-modulation header extraction, continuous-wave (CW) sources, wavelength conversion modules and a multiple-wavelength PPM Routing Table (MW-PPRT). The proposed MW-PPRT uses only a single-bitwise optical AND-gate to carry out fast correlation between the packet header and entire possible entries in the Routing Table. In addition, MW-PPRT offers the capability of simultaneously generating the Routing Table patterns for parallel header processing in PPM-HPs. The proposed router is investigated and simulated to show the ultrafast processing, wavelength Routing and the optical signal-to-noise ratio (OSNR) performance.
Chengzhong Xu - One of the best experts on this subject based on the ideXlab platform.
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elastic Routing Table with provable performance for congestion control in dht networks
IEEE Transactions on Parallel and Distributed Systems, 2010Co-Authors: Haiying Shen, Chengzhong XuAbstract:Consistent hashing-based DHT networks have an inherent load balancing problem. The problem becomes more severe in heterogeneous networks with nonuniform and time-varying popular files. Existing DHT load balancing algorithms are mainly focused on the issues caused by node heterogeneity. To deal with skewed lookups, this paper presents an elastic Routing Table (ERT) mechanism for query load balancing, based on the observation that high-degree nodes tend to receive more traffic load. The mechanism allows each node to have a Routing Table of variable size corresponding to node capacities. The indegree and outdegree of the Routing Table can also be adjusted dynamically in response to the change of file popularity and network churn. Theoretical analysis proves that the Routing Table degree is bounded. The ERT mechanism facilitates locality-aware randomized query forwarding to further improve lookup efficiency. By relating query forwarding to a supermarket customer service model, we prove that a two-way randomized query forwarding policy should lead to an exponential improvement in query processing time over random walking. Simulation results demonstrate the effectiveness of the ERT mechanism and its related query forwarding policy for congestion and query load balancing. In comparison with existing "virtual-server?-based load balancing algorithms and other Routing Table control approaches, the ERT-based congestion control protocol yields significant improvement in query lookup efficiency.
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elastic Routing Table with provable performance for congestion control in dht networks
International Conference on Distributed Computing Systems, 2006Co-Authors: Haiying Shen, Chengzhong XuAbstract:Distributed hash Table (DHT) networks based on consistent hashing functions have an inherent load balancing problem. The problem becomes more severe due to the heterogeneity of network nodes and the non-uniform and timevarying file popularity. Existing DHT load balancing algorithms are mainly focused on the issues caused by node heterogeneity. To deal with skewed lookups, this paper presents an elastic Routing Table (ERT) mechanism for query load balancing, based on the observation that high degree nodes tend to experience more traffic load. The mechanism allows each node to have a Routing Table of variable size corresponding to its capacity. The indegree and outdegree of the Routing Table can also be adjusted dynamically in response to the change of file popularity and network churn. Theoretical analysis proves the Routing Table degree is bounded. The ERT mechanism facilitates locality-aware randomized query forwarding to further improve lookup efficiency. By relating query forwarding to a supermarket customer service model, we prove a 2-way randomized query forwarding policy leads to an exponential improvement in query processing time over random walking. Simulation results demonstrate the effectiveness of the ERT mechanism and its related query forwarding policy for congestion and query load balancing. In comparison with the existing "virtual-server"-based load balancing algorithm and other Routing Table control approaches, the ERT-based congestion control protocol yields significant improvements in query lookup efficiency.
Arun K Somani - One of the best experts on this subject based on the ideXlab platform.
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high speed ip Routing with binary decision diagrams based hardware address lookup engine
IEEE Journal on Selected Areas in Communications, 2003Co-Authors: R Sangireddy, Arun K SomaniAbstract:With a rapid increase in the data transmission link rates and an immense continuous growth in the Internet traffic, the demand for routers that perform Internet protocol packet forwarding at high speed and throughput is ever increasing. The key issue in the router performance is the IP address lookup mechanism based on the longest prefix matching scheme. Earlier work on fast Internet protocol version 4 (IPv4) Routing Table lookup includes, software mechanisms based on tree traversal or binary search methods, and hardware schemes based on content addressable memory (CAM), memory lookups and the CPU caching. These schemes depend on the memory access technology which limits their performance. The paper presents a binary decision diagrams (BDDs) based optimized combinational logic for an efficient implementation of a fast address lookup scheme in reconfigurable hardware. The results show that the BDD hardware engine gives a throughput of up to 175.7 million lookups per second (Ml/s) for a large AADS Routing Table with 33 796 prefixes, a throughput of up to 168.6 Ml/s for an MAE-West Routing Table with 29 487 prefixes, and a throughput of up to 229.3 Ml/s for the Pacbell Routing Table with 6822 prefixes. Besides the performance of the scheme, Routing Table update and the scalability to Internet protocol version 6 (IPv6) issues are discussed.
Yasuhiro Ohara - One of the best experts on this subject based on the ideXlab platform.
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poptrie a compressed trie with population count for fast and scalable software ip Routing Table lookup
ACM Special Interest Group on Data Communication, 2015Co-Authors: Hirochika Asai, Yasuhiro OharaAbstract:Internet of Things leads to Routing Table explosion. An inexpensive approach for IP Routing Table lookup is required against ever growing size of the Internet. We contribute by a fast and scalable software Routing lookup algorithm based on a multiway trie, called Poptrie. Named after our approach to traversing the tree, it leverages the population count instruction on bit-vector indices for the descendant nodes to compress the data structure within the CPU cache. Poptrie outperforms the state-of-the-art technologies, Tree BitMap, DXR and SAIL, in all of the evaluations using random and real destination queries on 35 Routing Tables, including the real global tier-1 ISP's full-route Routing Table. Poptrie peaks between 174 and over 240 Million lookups per second (Mlps) with a single core and Tables with 500--800k routes, consistently 4--578% faster than all competing algorithms in all the tests we ran. We provide the comprehensive performance evaluation, remarkably with the CPU cycle analysis. This paper shows the suitability of Poptrie in the future Internet including IPv6, where a larger route Table is expected with longer prefixes.
S Iftekharul M Alam - One of the best experts on this subject based on the ideXlab platform.
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fast Routing Table lookup based on deterministic multi hashing
International Conference on Network Protocols, 2010Co-Authors: Zhuo Huang, David Lin, Jihkwon Peir, Shigang Chen, S Iftekharul M AlamAbstract:New generations of video, voice, high-performance computing and social networking applications have continuously driven the development of novel Routing technologies for higher packet forwarding speeds to meet the future Internet demand. One of the fundamental design issues for core routers is fast Routing Table lookup, which is a key problem at the network layer of the Internet protocol suite. It is difficult to scale the current TCAM-based or trie-based solutions for future Routing Tables due to increasing Table size, longer prefix length, and demands for higher throughput. This paper focuses on hash-based lookup solutions that have the potential of offering high throughput at one memory access per packet. We design the first deterministic multi-hashing scheme with small indexing overhead, which evenly distributes address prefixes to hash buckets for Routing-information storage. We minimize both the size of each bucket and the number of buckets that need to be fetched to the network processor for packet forwarding. Consequently, near-optimal Routing throughput is achieved. Performance evaluations demonstrate that the proposed deterministic multi-hashing scheme can maintain a constant lookup rate of over 250 million packets per second with today's commodity SRAM, which is much faster than the existing hashing schemes.
