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Chapter 1Introduction pfailure is presented, using the default ranging algorithm of the DOCSIS protocol.This algorithm adjusts the transmission power every time a station fails to range withthe headend. The same authors in [106] and [105] proposed a persistent rangingalgorithm, where stations try to retransmit using the same transmission power levelfor a number of attempts. Only after this limit is reached are the power parametersmodified and the process started again. Sdralia showed that the persistence rangingalgorithm performs better than the default ranging algorithm of the DOCSIS 1.0protocol, where a reduction of ≈ 38% was achieved in the recovery time.For the IEEE 802.14 protocol, Sala et al. [93] studied the performance of three CRAs(p-persistence, binary exponential backoff and splitting tree algorithm) in case ofregistration on power-up. The authors found that even in the worst case, the p-persistence algorithm performs better than the splitting tree algorithm up to ≈ 2000stations.e) Performance comparisons of CATV protocols; An investigation of protocol issuesand performance comparisons between IEEE 802.14 vs. DOCSIS can be found inGolmie et al. [42] and Smythe et al. [108]. Performance comparisons betweenDOCSIS vs. DVB/DAVIC are reviewed in Smythe et al. [109], [110], [111] and forcomparisons between “DVB/DAVIC vs. IEEE 802.14 vs. DOCSIS can be found inRangel et al. [84]. Here, the comparisons focus mainly on the capacity of theupstream channel to deliver several traffic types and packet sizes, using differentparameters of configuration.From the literature overview, there is a lack of studies that address the scalability,performance and optimisation of the DVB/DAVIC protocol. The first to report a briefanalysis of the performance of the DVB/DAVIC protocol was Schunke [100]. Thisanalysis focused on the performance of the three access modes of the DVB/DAVICprotocol (contention, reservation and fixed-rate) for the support of CBR (64-kbps with48-byte packets) and bursty traffic (64 kbps with 1.6-Kbytes), using a network size of50 stations and simulation time of 5 seconds. Simulation results revealed that systemperformance directly depends of the access mode that is chosen for the current trafficload. The contention access mode is only suitable for a light traffic load, whereas fixed-1-15