PDF of this tutorialAll Internet end users want access systems to provide increasingly higher speeds at a reasonable cost. Many users also want their Internet access to be closely coupled with the means they use to access other services. What are the challenges to measure against in meeting these needs of Internet users?
As described in this paper, the first challenge—the technology challenge—has been met vigorously by ingenious network providers and equipment vendors who have created a wide variety of high-speed access systems.
The second challenge is cost. New technology is usually costly, and the difficult challenge of meeting cost targets can take longer than access providers and end users wish. Today, the lag from technology creation to economic prove-in is the throttle regulating the pace at which emerging high-speed technologies gain widespread acceptance.
As access providers conquer the first two challenges and become successful in providing low-cost, high-speed access systems, it is already clear that new challenges will arise. For example, some access systems achieve high peak burst rates by sharing broadband-access media among many users. Eventually, all systems may find it beneficial to use shared links in portions of the access network. Shared systems have different network-engineering considerations from individual circuit-based systems, so we can expect shared systems to spawn new network engineering challenges for dealing with congestion, quality of service (QoS), and other performance criteria.
Finally, there are challenges in meeting the needs of users who see benefits in having Internet access combined with access to other services such as entertainment video and work-at-home intranets. Solutions such as virtual networks are being considered to address these needs, and access is an important enabler of these multiservice, multimedia solutions.
