With recent standardization and deployment of LTE eMBMS, cellular multicast is gaining traction as a method efficiently using wireless spectrum to deliver large amounts multimedia data multiple cell sites. Cellular operators still seek methods performing optimal resource allocation in eMBMS based on complete understanding the complex interactions among number mechanisms: coding scheme, resources allocated unicast users their scheduling at base stations, group satisfy user experience its...

As the number of wireless users and per-user bandwidth demands continue to increase, both vendor carrier communities agree that networks must evolve toward more dense deployments. So-called heterogeneous are a commonly proposed evolution, whereby existing macrocellular supplemented with an underlay small cells. The placement new small-cell sites is typically determined based on various location-dependent factors such as radio propagation calculations, user densities, measurements congestion...

To accommodate the increasing demands for bandwidth, Internet Service Providers (ISPs) have deployed higher-speed links and reconfigurable optical add drop multiplexers (ROADMs) in their backbone networks. address reliability challenges due to failures planned outages, ISPs typically use two routers at each central office a dual-home configuration. Thus IP layer, redundant as well transport equipment interconnect them are provide through node path diversity. However, adding such resources...

In this paper, the concept of transmission phase shift an impendance-matching network (IMN) has been introduced. The generalized two-port parameters matching circuit, which matches arbitrary complex load to a different source impedance incorporating phase, derived. general, IMNs are electrically asymmetric; however, there exist only two distinct values shifts (180° apart) for given and networks symmetric, irrespective choice design topology. Simple examples symmetric like single parallel...

This paper provides the design guidelines for a dual-band rat-race coupler and Gysel power divider with two different amplitude imbalances. The conditions are established based on electrical nature of C-section coupled lines/ T-structure/ $\Pi$-structures instead using equivalent transmission lines. It has been shown here that same equations can be utilized in divider. solved numerically to obtain parameters proposed possible application division ratios is presented polarization controlled...

We propose a new data declustering scheme for range queries. Our is based on Golden Ratio Sequences (GRS), which have found applications in broadcast disks, hashing, packet routing, etc. show by analysis and simulation that GRS nearly the best possible 2-dimensional Specifically, it when number of disks (M) at most 22; has response time one more than M/spl les/94; three les/550. also outperforms cyclic scheme-a recently proposed was shown to better performance previously known schemes this...

We report an interesting case of parasitic fibroid which developed from a morcellation remnant following laparoscopic myomectomy. The patient presented with incidental finding pelvic mass in 2005. She underwent myomectomy for myoma extending the Pouch Douglas to both sides broad ligament. subsequently abdominal pain 3 years later 2008. total hysterectomy removal ligament fibroids. During her hysterectomy, right lumbar attached omentum was detected, excised laparoscopically. Histopathology...

We study a network model in which each link is associated with set of delays and costs. These costs are function the reflect prices paid return for delay guarantees. Such cost structure can setting service provider provides multiple classes different price guarantee class. given source node s, sink t, an end-to-end constraint D. Our aim to choose s-t path determine per guarantees along this so as satisfy D while minimizing total incurred. In case where known, we optimally partition into...

This work has been motivated by the need to test interoperability of systems carrying voice calls over IP network. The (VoIP) must be integrated and interoperate with existing public switched telephone network (PSTN) before they are widely adopted. Standards have developed address this problem, but unfortunately different standards bodies commercial consortiums defined standards. Furthermore, prevailing VoIP standard such as H.323 is incomplete, complex, presents implementers vendors...

A systematic approach to synthesize multiport ( N-port) network with desired characteristics, for a given topology, has been proposed. The heart of the algorithm lies novel port decomposition technique introduced here, wherein reduced two-port (2PN) is obtained by short-circuiting remaining N-2 ports original topology. This easily analyzed in terms its unknown design parameters and can be compared known characteristics provide subset equations. Iteratively proceeding this approach, one...

The problem of fast address lookup is crucial to routing and thus has received considerable attention. Most the work in this field focused on improving speed individual accesses-independent from underlying access pattern. Gupta et al. (2000) proposed an efficient data structure exploit bias This technique achieves faster lookups for more frequently accessed keys while bounding worst case time; fact it (near) optimal under constraints performance. However,it needs be rebuilt periodically...

Meeting IPTV's quality of service constraints (such as low latency and loss) requires designing the right combination underlying IP-transport, restoration, video packet recovery methods. Carriers use link-based fast reroute (FRR) primary transport restoration method to achieve this goal. Although we can carefully tune link weights in IP routing protocol avoid traffic overlap from FRR during single failures, multiple failures still cause path long-distance networks. By having FRR, IGP,...

Links in an IP network are unidirectional but currently routed over bidirectional optical circuits with identical A→Z and Z→A capacities. Potentially there could be savings if the two directions of circuit treated independently. In this study possible savings, we have quantified asymmetry traffic on a current large backbone. A theoretical greenfield similarly asymmetric is modeled, it shown that use to satisfy demands provides significant equipment savings. We consider benefits approach...

Four-port couplers are the fundamental building blocks of large-scale passive beamforming network design. They find application in design antenna feed networks, power combiners and dividers, balanced mixers amplifiers.

In this paper we present techniques and protocols for protecting a network against multiple link failures. The existing link-based restoration with MPLS Fast Re-route (FRR) is fast, but can create congestion by overloading edges, which undesirable since many applications are sensitive to congestion-related packet loss. problem exacerbated failures, frequent enough be of concern in production networks. investigate enhancements FRR the presence failures through protocol design. We describe...

A theory of coupled characteristic modes is developed for computing the eigenmodes a array using isolated elements and corresponding mutual interaction matrix. The systematic blending matrix block partitioning method orthogonal properties eigenvectors provide generalized formulation considering all modes. Later, closed-form solutions have been derived dominant with assumption one-to-one mode coupling elements. idea has further extended two-to-two modeling which conforms into fourth-order...

Change management has been a long-standing challenge for network operations. The large scale and diversity of networks, their complex dependencies, continuous evolution through technology software updates combined with the risk service impact create tremendous challenges to effectively manage changes. In this paper, we use data from provider experiences operations teams highlight need quick easy adaptation change capabilities keep up We propose new framework CORNET (COmposition fRamework...

The authors describe a methodology for evaluating the performability (combined performance and reliability) of large communications networks. Networks are represented by 4-level hierarchical model, consisting traffic matrix, network graph, “components” representing failure modes, reliability information. Network states assignments modes to components, which usually represent elements their key modules, although they can be more abstract. components binary or multi-modal, each may change set...

An asymmetric structure is in general never equivalent to a quarter-wavelength (symmetric) transmission line. However this letter theory has been derived, wherein each of the six lines conventional rat-race coupler can be replaced by any arbitrary connected identical orientation. The theorem exploits mirror-symmetry coupler, even when used as its building block. It also observed that every an frequency independent symmetric representation coupler. Asymmetric-T example asymmetric-structure...