TOPOLOGICAL ANALYSIS OF COMPLEX OPTICAL TRANSPORT NETWORKS

SDH (Synchronous Digital Hierarchy) is the standard technology for information transmission in broadband optical networks. Unlike the Internet, SDH networks are strictly planned — rings, meshes, stars or tree-branches topologies are designed to connect their basic elements. In this work we show that the SDH network operated by Telefónica in Spain presents a power-law scaling in the degree distribution (P(k) ~ k-γ) both at the national and provincial levels. The empirically obtained scaling exponents γ are consistent with those observed in other heterogeneous complex networks. The Spanish SDH network also displays small world properties with a high clustering and short path length similar to the Internet routers network. The province subnetworks experience similar traits with regards to such properties. Considering factors such as network design policies, user demand, geographical location and types of equipment, we propose an ad hoc computational model in order to reproduce these topological properties.

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MODELING THE TOPOLOGY OF SDH NETWORKS

International Journal of Modern Physics C ◽

10.1142/s0129183108013369 ◽

2008 ◽

Vol 19 (12) ◽

pp. 1809-1820 ◽

Cited By ~ 10

Author(s):

A. SANTIAGO ◽

J. P. CÁRDENAS ◽

M. L. MOURONTE ◽

V. FELIU ◽

R. M. BENITO

Keyword(s):

Optical Networks ◽

Power Law ◽

Ad Hoc ◽

Small World ◽

The Internet ◽

Topological Properties ◽

Small World Networks ◽

Synchronous Digital Hierarchy ◽

Worldwide Web ◽

Real Complex

SDH (Synchronous Digital Hierarchy) is the standard technology for the information transmission in broadband optical networks. Unlike the Internet, SDH networks are strictly planned; rings, meshes, stars, or tree-branches topologies are designed to connect their basic elements. In spite of that, we have found that the SDH network operated by Telefónica in Spain shares remarkable topological properties with other real complex networks empirically analyzed, such as the worldwide web network. In particular, we have found power-law scaling in the degree distribution (P(k) ~ k-γ) and properties of small world networks. Considering real planning directives that take into account geographical and technological variables, we propose an ad hoc computational model that reproduces the aforementioned topological traits observed in the Spanish SDH network.

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Connection setup and traffic aggregation in IP-based Elastic Optical Networks (EON)

International Journal of Communications ◽

10.46300/9107.2020.14.8 ◽

2020 ◽

Vol 14 ◽

Keyword(s):

Optical Networks ◽

Network Structure ◽

Research Work ◽

The Internet ◽

Potential Candidate ◽

Transport Networks ◽

Optical Transport Networks ◽

Optical Wavelength ◽

Traffic Scenario ◽

Multilayer Routing

To overcome the challenges of the increased IP traffic volume on the Internet, the IP/MPLS-based fixed grid DWDM network structure was proposed, which makes the interaction between both the IP layer and the optical wavelength routed fixed DWDM layer applicable. However, the deployment of this architecture was not only expensive, but power-consuming. The emerging optical Flexgrid networks technology is nowadays suggested to be the potential candidate for future optical transport networks. This is because it provides extremely flexible and spectrally effective resources utilisation. Therefore, it has attracted the attention of network operators, optical networks equipment manufacturers and the wider research and development society. In this research work, we propose a novel multilayer routing scheme for an IP/MPLS-based optical Flex-grid network, which is based on the protocol suite defined by the GMPLS architecture. Furthermore, we evaluate its behaviour in an online dynamic traffic scenario.

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An analytical model for the integration of wireless mobile ad hoc network and the Internet

China-Ireland International Conference on Information and Communications Technologies (CIICT 2008) ◽

10.1049/cp:20080912 ◽

2008 ◽

Author(s):

K. Ur Rahman Khan ◽

R.U. Zaman ◽

A. Venugopal Reddy

Keyword(s):

Analytical Model ◽

Ad Hoc Network ◽

Ad Hoc ◽

Mobile Ad Hoc Network ◽

The Internet ◽

Mobile Ad Hoc ◽

Wireless Mobile

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Sensor System: A Survey of Sensor Type, Ad Hoc Network Topology and Energy Harvesting Techniques

Electronics ◽

10.3390/electronics10020219 ◽

2021 ◽

Vol 10 (2) ◽

pp. 219

Author(s):

Phuoc Duc Nguyen ◽

Lok-won Kim

Keyword(s):

Energy Harvesting ◽

Large Scale ◽

Ad Hoc ◽

Sensor Nodes ◽

Sensor System ◽

Wireless Sensor ◽

The Internet ◽

Original Research ◽

Energy Scavenging ◽

Term Operation

People nowadays are entering an era of rapid evolution due to the generation of massive amounts of data. Such information is produced with an enormous contribution from the use of billions of sensing devices equipped with in situ signal processing and communication capabilities which form wireless sensor networks (WSNs). As the number of small devices connected to the Internet is higher than 50 billion, the Internet of Things (IoT) devices focus on sensing accuracy, communication efficiency, and low power consumption because IoT device deployment is mainly for correct information acquisition, remote node accessing, and longer-term operation with lower battery changing requirements. Thus, recently, there have been rich activities for original research in these domains. Various sensors used by processing devices can be heterogeneous or homogeneous. Since the devices are primarily expected to operate independently in an autonomous manner, the abilities of connection, communication, and ambient energy scavenging play significant roles, especially in a large-scale deployment. This paper classifies wireless sensor nodes into two major categories based the types of the sensor array (heterogeneous/homogeneous). It also emphasizes on the utilization of ad hoc networking and energy harvesting mechanisms as a fundamental cornerstone to building a self-governing, sustainable, and perpetually-operated sensor system. We review systems representative of each category and depict trends in system development.

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Energy challenges in optical access and aggregation networks

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2014.0435 ◽

2016 ◽

Vol 374 (2062) ◽

pp. 20140435 ◽

Cited By ~ 8

Author(s):

Daniel C. Kilper ◽

Houman Rastegarfar

Keyword(s):

Optical Networks ◽

Optical Switching ◽

Energy Use ◽

Future Internet ◽

Critical Issue ◽

Optical Systems ◽

The Internet ◽

Total System ◽

Single Chip ◽

Processor Core

Scalability is a critical issue for access and aggregation networks as they must support the growth in both the size of data capacity demands and the multiplicity of access points. The number of connected devices, the Internet of Things, is growing to the tens of billions. Prevailing communication paradigms are reaching physical limitations that make continued growth problematic. Challenges are emerging in electronic and optical systems and energy increasingly plays a central role. With the spectral efficiency of optical systems approaching the Shannon limit, increasing parallelism is required to support higher capacities. For electronic systems, as the density and speed increases, the total system energy, thermal density and energy per bit are moving into regimes that become impractical to support—for example requiring single-chip processor powers above the 100 W limit common today. We examine communication network scaling and energy use from the Internet core down to the computer processor core and consider implications for optical networks. Optical switching in data centres is identified as a potential model from which scalable access and aggregation networks for the future Internet, with the application of integrated photonic devices and intelligent hybrid networking, will emerge.

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Deviant writing and youth identity

Chinese Language & Discourse ◽

10.1075/cld.2.1.03liu ◽

2011 ◽

Vol 2 (1) ◽

pp. 58-79 ◽

Cited By ~ 6

Author(s):

Jin Liu

Keyword(s):

Ad Hoc ◽

Dominant Strategy ◽

Written Language ◽

The Internet ◽

Youth Identity ◽

Visual Style ◽

Chinese Writing System ◽

Standard Chinese ◽

Youth Language ◽

Chinese Writing

This paper examines the emergence of the representation of dialect with Chinese characters (fangyan wenzihua) on the Internet. The online dialect writing is primarily identified as a subject of Internet language and youth language study. The CMC discourse as a hybrid register mixing spoken and written language features facilitates the written use of oral dialect on the Internet. Deviating from the standard Chinese writing system, the Internet-savvy youth transcribe their native dialects on an ad hoc basis, which celebrates multiplicity, creativity, individuality and resists uniformity, standardization, and institutionalization. Taking the SHN website (www.shanghaining.com) as a case study, the paper discusses how the written Shanghai Wu words are explored to mark a distinct visual style and to articulate a distinct local youth identity. Furthermore, this paper examines the dominant strategy of phonetic borrowing in dialect transcription on the Internet. It is argued that diachronically, the youth’s phonocentric obsession tapped into the May Fourth tradition of the baihua vernacular movement that was heavily influenced by the European logocentrism; and synchronically, the celebration of dialect sound on the Internet echoes the contemporary soundscape of local dialects formed in the mass media in recent years.

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