The optical networking technology that suffered in the post - dot - com crash
several years ago has since recovered and is once again poised for rapid growth
due to the exhaustion of available bandwidth. Today, photonics networks transport
Internet data over large distances in long - haul and metropolitan networks.
Improvements in photonics components and silicon chips have enabled several
new technologies that are changing how these networks are built and operated.
While the network core has always been optical Internet access traditionally
secured through wireline access networks, various DSL (ADSL, VDSL, VDSL2),
cable (DOCSIS 2.0, DOCSIS 3.0), and passive optical networks (BPON, GPON,
EPON) have been used. The challenge in the YouTube and Facebook era is to
manage the amount of traffi c and service growth while securing or preferably
growing revenue. In particular, dynamic bandwidth allocation (DBA) in passive
optical networks (PON) presents a key issue for providing effi cient and fair utilization
of the PON upstream bandwidth while supporting the quality of service
(QoS) requirements for different traffi c classes.
Wireless networks have been booming largely independently of changes in
photonic and wireline networks. WLAN (IEEE 802.11), Zigbee (IEEE 802.15.4),
WiMax (IEEE 802.16), and 3G/4G cellular telephony are growing quickly, while
60 GHz, wireless sensor networks and cognitive radios are starting to be considered
for volume deployment. In the next 10 years, Internet access will likely
become dominated by mobile wireless terminals. The fourth - generation wireless
system (4G) is seen as an evolution and an integration of existing wireless
network architectures such as 2G and 3G with new ones such as mobile ad
hoc networks (MANETs). There are several challenges ahead to make this
integration happen. Many issues in 4G related to provisioning of ubiquitous and
seamless service access with different underlying wireless technologies remain to
be solved.
The main objectives of next - generation networks are to effi ciently provide
adequate network quality to multimedia applications with high bandwidth and
strict QoS requirements and to seamlessly integrate mobile and fi xed architectures.
These objectives are becoming increasingly relevant due to the huge increment
of multimedia applications that require better quality than plain best effort.
Wireless and wireline next - generation networks that access the photonic core
will be as ubiquitous as traditional telephone networks, and today ’ s engineering
students must be prepared to meet the challenges of their development and
deployment.