Integrated Wireless-pon access Network Architectures Milos Milosavljevic

Chapter 2 Next Generation Access Networks 
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encryption key associated with each ONU is sent in the secured upstream data since individual 
ONUs cannot have access to upstream transmissions of others. 
Significantly, with the emerging applications and consequently ever increasing demand for 
bandwidth, PONs capable of accommodating even higher bandwidth were timely promoted. 
Towards this direction a task group was formed by IEEE [15, 16] and FSAN [17] and recently 
standardised what is known as the 10G-EPON, particularly aiming at achieving symmetrical 10 
Gbit/s for distances of at least 20 km and 1:32 split [18, 19]. Chromatic dispersion may become 
significant over the standard single mode fibre (SSMF) at these distances and data rates 
therefore state-of-the-art transceivers need to be developed [20]. These systems also provide 
backward compatibility with optical distribution networks currently deployed. 
2.2 WiMAX Architecture and Standards 
WiMAX is a broadband wireless access network developed to compete with traditional wireline 
access technologies by providing mobile, high-speed data and telecommunications services 
comparable to emerging 4G technologies [21]. It can support fixed, nomadic and mobile access 
based primarily on point-to-multipoint transmission [22]. As illustrated in Figure 2-3 data 
transmission in WiMAX is carried out between an internet service provider (ISP) and base 
stations [23], with the former located in the central office, connecting the access network with 
the internet backbone and the later at subscriber close proximity delivering data to end users. 
WiMAX is capable to support relatively high data rates in the range of 75 Mbit/s with 64-QAM 
modulation in 20 MHz bandwidth. The WiMAX standards also facilitate scalable bandwidth 
and data rates, adaptive modulation and coding based on received signal-to-noise ratio (SNR) 
and state-of-the-art forward error correction techniques [24, 25]. In the same time they provide 

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