Abstract: Core networks of the future will have a
translucent and eventually transparent optical
structure. Ultra-high-speed end-to-end connectiv-
ity with high quality of service and high reliability
will be realized through the exploitation of opti-
mized protocols and lightpath routing algorithms.
These algorithms will complement a flexible con-
trol and management plane integrated in the
proposed solution. Physical layer impairments
and optical performance are monitored and
incorporated in impairment-aware lightpath rout-
ing algorithms. These algorithms will be integrat-
ed into a novel dynamic network planning tool
that will consider dynamic traffic characteristics,
a reconfigurable optical layer, and varying physi-
cal impairment and component characteristics.
The network planning tool along with extended
control planes will make it possible to realize the
vision of optical transparency. This article pre-
sents a novel framework that addresses dynamic
cross-layer network planning and optimization
while considering the development of a future
transport network infrastructure.
Abstract: In this paper, we present a new hybrid optical burst switch architecture (HOBS) that takes advantage of the pre-transmission idle
time during lightpath establishment. In dynamic circuit switching (wavelength routing) networks, capacity is immediately hardreserved
upon the arrival of a setup message at a node, but it is used at least a round-trip time delay later. This waste of resources
is significant in optical multi-gigabit networks and can be used to transmit traffic of a lower class of service in a non-competing
way. The proposed hybrid OBS architecture, takes advantage of this idle time to transmit one-way optical bursts of a lower class of
service, while high priority data explicitly requests and establishes end-to-end lightpaths. In the proposed scheme, the two control
planes (two-way and one-way OBS reservation) are merged, in the sense that each SETUP message, used for the two-way lightpath
establishment, is associated with one-way burst transmission and therefore it is modified to carry routing and overhead information
for the one-way traffic as well. In this paper, we present the main architectural features of the proposed hybrid scheme and further
we assess its performance by conducting simulation experiments on the NSF net backbone topology. The extensive network study
revealed that the proposed hybrid architecture can achieve and sustain an adequate burst transmission rate with a finite worst case
delay.
Abstract: Avertical perspective, ranging from management
and routing to physical layer options, concerning dynamic
network monitoring and compensation of impairments
(M&C),is given.Feasibility, reliability,and performance
improvements on reconfigurable transparent networksare
expected to arise from the consolidated assessment of network management and control specifications, as a more accurate evaluation of available M&C techniques. In the network
layer,physical parameters aware algorithms are foreseen to
pursue reliable network performance. In the physical layer,
some new M&C methods were developed and rating of the state-of-the-art reported in literature is given. Optical monitoring implementation and viability is discussed.
Abstract: An enhanced impairment-aware path computation element (EPCE) for dynamic
transparent opticalnetworks is proposed and experimentally evaluated. The obtained results show
that by using the EPCE, light-path setup times of few seconds are achieved.
Abstract: This article studies the transmission control
protocol (TCP) synchronization effect in optical burst
switched networks.Synchronization of TCP flows appears
when optical bursts with segments from different flows inside
are dropped in the network causing flow congestion windows decreasing simultaneously. In this article,this imminent
effect is studied with different assembly schemes and network scenarios.Different metrics are applied to quantitatively assess synchronization with classical assembly
schemes.A new burst assembly scheme is proposed that
statically or dynamically allocates flows to multiple assembly queues to control flow aggregation within the assembly
cycle.The effectiveness of the scheme has been evaluated,
showing a good improvement in optical link utilization