Quality of Service (QoS) mechanisms in networks
supporting mobile Internet communications give
rise to new threats: these mechanisms could be abused
by malicious entities launching so-called Denial of Service
(DoS) attacks. If the network can not efficiently check the
credibility of a QoS-request during a handover process,
malicious entities could flood the network with bogus QoSrequests;
if the authentication check is performed by means
of an AAA protocol before the access network commits its
resources to the request, the authentication process may
not only introduce a notable latency to the handover process,
but also generate an extensive traffic which degrades
the signaling capacity in the network when there are a considerable
amount of malicious requests. In order to defend
against these kinds of attacks and meet the low-latency
micro-mobility handover requirement, we 1propose to have
a preliminary authentication check with a cookie-based
mechanism before processing the requests and performing
authentication and authorization. The performance evaluation
shows that the cookie-based mechanism is efficient in
dealing with the identified issues.
Single-hop WDM networks with a central Passive Star Coupler (PSC), as well as single-hop networks with
a central Arrayed-Waveguide Grating (AWG) and a single transceiver at each node, have been extensively
studied as solutions for the quickly increasing amounts of unicast and multicast traffic in the metropolitan
area. The main bottlenecks of these networks are the lack of spatial wavelength reuse in the studied PSC
based networks and the single transceiver in the studied AWG based metro WDM networks. In this paper
we develop and evaluate the FT EE ???? FREE AWG network, which is based on a central AWG and has arrays
of fixed-tuned transmitters and receivers at each node. Transceiver arrays are a mature technology, making
the proposed network practical. In addition, the transmitter arrays allow for high speed signaling over the
AWG while the receiver arrays relieve the receiver bottleneck arising from multicasting in conjunction with
spatial wavelength reuse on the AWG. Our results from probabilistic analysis and simulation indicate that
the FTEE ???? FREE AWG network gives particularly good throughput-delay performance for a mix of unicast
and multicast traffic.