In this paper we determine the optimal fraction c∗ of the uplink channel capacity that should be dedicated to the contention channel in a DOCSIS cable network in order to minimize its mean response time. For this purpose, we have developed an open queueing network with a non-standard form of blocking consisting of tens to hundreds of nodes. The network contains several types of customers that e...

Several decades of research in underwater communication and networking has resulted in novel and innovative solutions to combat challenges such as long delay spread, rapid channel variation, significant Doppler, high levels of nonGaussian noise, limited bandwidth and long propagation delays. Many of the physical layer solutions can be tested by transmitting carefully designed signals, recording...

The paper describes the upstream MAC protocol employed by the HP cable-modem for hybridber-coax networks. The protocol, called MXL, divides the upstream channel into two logical channels: a contention channel and a reserved channel. Cablemodem stations that need to send data have to reserve su cient bandwidth in the reserved channel. In order to send their reservation request, the stations have...

The rapid international development of the mobile phone business has led to significant advances in communications engineering. However, the experience base for underwater acoustic communications is much more limited. Meanwhile, the ocean channel has unique characteristics, so that one cannot assume radio modulation schemes are suitable for acoustic communications in the ocean (and vice versa)....