A theoretical framework for network monitoring exploiting segment routing counters

Self-driving networks represent the next step of network management techniques in the close future. A fundamental point for such an evolution is the use of Machine Learning based solutions to extract information from data coming from network devices during their activity. In this work we focus on a new type of data, available thanks to the definition of the novel SRv6 paradigm, referred to as SRv6 Traffic Counters (SRTCs). SRTCs provide aggregated measurements related to forwarding operations performed by SRv6 routers. In this work a detailed description of different SRTCs types (SR.INT, PISD, PSID.TM and POL) is provided and their relationships is formalized. The theoretical framework deployed is used to identify, on the basis of network configuration parameters of both SRv6 and IGP protocols, the minimum set of independent SRTCs to characterize the Network Status: we show that about the 80% of counters can be neglected with no information loss. We also apply our framework to two use cases: i) Traffic Matrix (TM) Assessment and ii) Traffic Anomaly Detection. For the TM assessment, we show that in a partially deployed SRv6 scenario a specific type of SRTCs, i.e., PSID, is more reliable than other ones; on the contrary, in a fully deployed scenario POL and PSID.TM counters provide the full TM knowledge. For the Traffic Anomaly Detection case, we show that known solutions based on link load measurements can be improved when integrating SRTCs information

SOA-Based Optical Packet Switching Architectures

The service evolution and the rapid increase in traffic levels fuel the interest toward switching paradigms enabling the fast allocation of Wavelength Division Multiplexing WDM channels in an on demand fashion with fine granularities (microsecond scales). For this reason, in the last years, different optical switching paradigms have been proposed: optical-packet switching (OPS), optical-burst switching (OBS), wavelength-routed OBS, etc. Among the various all-optical switching paradigms, OPS attracts increasing attention. Owing to the high switching rate, Semiconductor Optical Amplifier (SOA) is a key technology to realize Optical Packet Switches. We propose some Optical Packet Switch (OPS) architectures and illustrate their realization in SOA technology. The effectiveness of the technology in reducing the power consumption is also analyzed. The chapter is organized in three sections. The main blocks (Switching Fabric, Wavelength Conversion stage, Synchronization stage) of an OPS are illustrated in Section 2 where we also show some examples of realizing wavelength converters and synchronizers in SOA technology. Section 3 introduces SOA-based single-stage and multi-stage switching fabrics. Finally the SOA-based OPS power consumption is investigated in Section 4

KAJIAN PROSES ISLAMISASI DI NUSANTARA (STUDI ANALISIS MASJID AL – MUBAROK DI DESA KACANGAN KECAMATAN BERBEK, KABUPATEN NGANJUK)

Penelitian ini dilatarbelakangi oleh banyaknya media penyebaran Islam di Nusantara, dan proses islamisasi yang terjadi di wilayah Kabupaten Nganjuk dengan keberadaan masjid Al-Mubarok.  Didirikan pada tahun 1831 Masehi oleh K.R.T Sosrokoesoemo I atau lebih di kenal dengan Kanjeng Jimat. Tujuan dari penelitian ini guna mengetahui sejarah berdirinya Masjid Al-Mubarok, dan Struktur bangunan Masjid Al-Mubarok. Penelitian ini menggunakan  metode deskriptif kualitatif dengan cara mendeskripsikan, menganalisis, dan membandingkan informasi dari hasil pengamatan keadaan dilapangan dengan kajian pustaka dari sumber resmi lainnya. Hasil dari penelitian ini yaitu Masjid Al-Mubarok sebagai masjid tertua sekaligus bangunan bersejarah di wilayah Kabupaten Nganjuk yang menjadi media Islamisasi di wilayah Kabupaten Nganjuk. Berdasarkan hasil tersebut dapat disimpulkan pengaruh Islam di Kabupaten Nganjuk berkembang sangat pesat, mengubah mayoritas kepercayaan masyarkat Kabupaten Nganjuk dari Hindu-Buddha menuju Islam sejak berdirinya masjid Al-Mubarok

School refusal behavior. role of personality styles, social functioning, and psychiatric symptoms in a sample of adolescent help-seekers

Objective: School refusal (SR) in adolescence represents an important risk factor associated with adverse consequences. Although many clinical features of adolescents presenting with SR have been studied, the relationship between SR and personality styles-specifically in the help-seeking population-remains unclear. The present study aimed at investigating differences in personality style, adaptive functioning, and symptomology between Italian help-seeking adolescents who refused (SRa) and did not refuse (non-SRa) to attend school, to provide preliminary evidence of personality patterns in adolescent help-seekers presenting with SR.Method: The study sample was comprised of 103 help-seeking adolescents (54 female, 49 male) aged 14-18 years. Participants were recruited during their first clinical visit and evaluated using the Shedler and Westen Assessment Procedure - Adolescent version (SWAP-A), the Hamilton Rating Scale for Depression (HAM-D), the Hamilton Rating Scale for Anxiety (HAM-A), the Maniac Rating Scale (MRS), the Global Assessment of Functioning (GAF), the Global Functioning Social Scale (GFSS), and the Global Functioning Role Scale (GFRS). Differences in the studied variables between SRa and non-SRa were measured and a multivariable logistic regression analysis was performed to identify possible predictive factors of SR.Results: SRa presented with more anxious and depressive symptomatology and worse social functioning compared to non-SRa. With respect to personality, SRa displayed more schizoid and schizotypal characteristics and fewer adaptive and healthy personality features. Irrespective of any differences between groups, SRa were largely characterized by inhibited-self-constricted and emotionally dysregulated personality styles.Conclusions: The results suggest that personality styles arc clinical features that may contribute to broadening our knowledge of SR behavior and aid in the detection of SRa, also in the help-seeking population. The findings have clinical, social, and political implications for prevention, diagnosis, and treatment, in both clinical and non-clinical settings. However, more data are needed on personality features to clarify their contribution to the more complex phenomenon of school absenteeism

Supporting RSVP in a Differentiated Service Domain: an Architectural Framework and a Scalability Analysis

This paper analyzes a framework to offer reservation of resources and QoS guarantees according to the Resource Reservation Protocol (RSVP) paradigm in a network cloud that supports a differentiated services architecture. The key elements are: intelligent Edge Devices; a flow admission and resource allocation method involving an Admission Control Server: "simple" core routers based on the differentiated services model. The main functionality of a client/server protocol between the Edge Devices and the Admission Control Server, called Simple Admission Control Protocol, is described. The proposed framework is referred to as Admission Control Server based Resource Allocation. Scalability is analyzed and compared with RSVP approach

Amplification effects of the send rate of TCP connection through an optical burst switching network

This paper investigates support for TCP RENO flows in an Optical Burst Switching (OBS) network. In particular we evaluate the TCP send-rate, i.e., the amount of data sent per time unit taking into account the burst assembly mechanism at the edge nodes of the OBS network and burst loss events inside the network. The analysis demonstrates an interesting phenomenon, that we call correlation benefit. This phenomenon is introduced by the aggregation mechanism and can give rise, in some conditions, to a significant increase in the TCP send-rate. These results are obtained by means of an analytical model, based on a Markovian approach, and have been validated via an intensive simulation campaign

Packet loss in a bufferless optical WDM switch employing shared tunable wavelength converters

We propose an architecture for a bufferless packet optical switch employing the wavelength dimension for contention resolution. The optical packet switch is equipped with tunable wavelength converters shared among the input lines. An analytical model Is proposed in order to determine the number of converters needed to satisfy prefixed packet loss probability constraints. This analytical model very accurately fits with simulations results. A sensitivity analysis of the required number of converters as a function of the main system parameters (number of input and output lines, number of wavelengths, …) and traffic parameters has been carried out. Making use of the introduced dimensioning procedure we have observed that the proposed architecture allows a saving in terms of employed number of converters with respect to the other architectures proposed in literature. Such a saving can reach about 95% of the number of converters

Interface counters in segment routing v6: a powerful instrument for traffic matrix assessment

In this work we investigate the use of Segment Routing version 6 (SRv6) interface counters to improve the Traffic Matrix (TM) assessment of an ISP network. SRv6 is a source routing solution for IPv6 networks: it allows defining a network path as a sequence of routers, represented by Segments Identifiers (SID), to be crossed, i.e. a Segment List (SL). SRv6 provides a new set of interface counters able to measure the packets/ bytes of Ingress/Egress flows exploiting the forwarding operations performed on the Segment Identifiers (SIDs) reported in the SLs. In this work, we formally define the contribution of SR counters in the TM computation procedure, by integrating them in the classical TM Assessment problem. The main outcome of the performance analysis are: i) SR counters can greatly reduce the estimation error and, ii) there is a correlation between the TM assessment improvement and the SLs structure