 | Issue: | Asia-Pacific III 2008 |
| Article no.: | 18 | |
| Topic: | Next-generation network and satellite convergence | |
| Author: | David Bettinger | |
| Title: | CTO | |
| Organisation: | iDirect Technologies | |
| PDF size: | 217KB |
About author
David Bettinger is the CTO and Senior Vice President of Engineering at iDirect; he previously served as iDirect’s VP of Engineering responsible for all hardware and software development. Mr Bettinger joined iDirect Technologies as the Director of Hardware Engineering. Mr Bettinger has been active in the satellite networking industry for over 15 years; prior to iDirect, Mr Bettinger was a senior member of the technical staff at Hughes Network Systems – Satellite Networks Division. Mr Bettinger is active in industry standards organizations and forums and is a member of the Telecommunications Industry Association (TIA), the EEE and the IPv6 Forum. David Bettinger is a graduate of Virginia Tech with a Master of Science degree in Electrical Engineering.
Article abstract
Today, satellites are mostly used for broadcasting and connectivity in remote areas or in extreme situations. The growth of centralized, Web-based enterprise applications has made full-time broadband access to every office and employee essential – even when primary networks fail and where terrestrial systems can’t reach. The true convergence between terrestrial and satellite networks needed to meet these demands calls for common routing protocols, network-wide quality of service, converged end-to-end VPNs, total network security and integration of network management software.
Full Article
For decades, satellite communications has been a highly specialized segment of the telecommunications industry. It’s a field distinguished by what are often considered miracles of engineering – videoconferencing on speeding military vehicles, IP broadband in the middle of the ocean and aboard airplanes, and cell phone coverage in the jungles of Africa and Latin America. However, despite these impressive feats, satellite communications has traditionally been foreign to many in the telecommunications industry. Many think it is applicable only in unique or extreme situations, without broader application. Today, that is changing. A new wave of demand for satellite connectivity is coming from an unlikely source – the world’s major terrestrial carriers. Broadband demand The world now runs on broadband, and it is bringing a new set of requirements for how businesses operate – as well as new operating challenges for terrestrial carriers. Today, broadband must be available everywhere. With the growth of centralized and increasingly Web-based enterprise applications, every office and employee of a major organization must now have equal access to a high-speed network. And broadband must be available at all times – even when primary networks fail or are not yet in place and in environments where terrestrial systems simply can’t reach. Terrestrial carriers have begun addressing this demand through the development of converged networks. These are typically Multi Protocol Label Switching (MPLS) networks, which operate like a circuit switch network, routing IP traffic securely across distinct customer networks. In 2004, BT unveiled the vision for its next-generation 21st Century Network. The sweeping plan called for a complete end-to-end IP network to replace its 16 discrete legacy networks, including a circuit-switched public telephone network. For BT, the 21st Century Network represents an ambitious response to rising customer demands for improved networking capabilities and a seamless user experience. With the development of next-generation networks, however, carriers are focusing not just on convergence but also on improving the integration of core terrestrial, wireless and satellite communications technology. While dramatically more powerful than the systems they are replacing, even next-generation networks carry limitations in reach, mobility, immediacy and functionality. Only when combined with satellite communications can they stretch broadband around the globe and serve every customer need, which is the ultimate next-generation goal. So, with the emergence of next-generation networks, satellite communications has begun to play a more pivotal, far-reaching role in the telecommunications industry. The next-generation integrated network Operators and carriers have been mixing terrestrial and satellite networks for decades to address many of the above demands. The development of hybrid networks – a blend of terrestrial, wireless and satellite functionality – is an established trend. However, while hybrid networks improve access to broadband, they fall short of delivering a seamless, fully functional network. Enterprises end up with multiple sub-networks to manage and are hindered by performance discrepancies across geographies and applications. From the service provider perspective, parallel networks are costly to maintain and inefficient, and network integration is a technology and management burden. Hybrid networks do not meet today’s universal demand for constant broadband connectivity. Both the terrestrial and satellite industries must refine the engineering of their systems to become wholly compatible. This requires a shared set of technological priorities. While there are many priorities that one could list, I have outlined a short-list of five primary requirements that will benefit next-generation converged networks, providing a new level of terrestrial and satellite integration. The majority of the tasks fall to the satellite industry; fortunately satellite technology leaders have already made significant progress in recent years. The five-point technology integration roadmap 1 – Share common routing protocols In most cases, satellite networks rely on the Routing Information Protocol (RIP) to transport data. However, RIP is an edge protocol. In the context of a hybrid network, IP data transported by a satellite network must be converted to Border Gateway Protocol (BGP) at a satellite hub and then to another protocol such as Open Sort Path First (OSPF) to make its way through the core terrestrial network. While this conversion process has sufficed for discrete applications, it does not easily scale to support a large network. To support next-generation networks, satellite technology providers are engineering their systems to directly support BGP, OSPF and other terrestrial protocols. This will introduce a more bandwidth-efficient use of satellite capacity and enable satellite systems to integrate seamlessly with large networks. For operators and service providers, it will lower operational costs and will enable them to manage a complete network, not just individual nodes. 2 – Achieving network-wide quality of service A critical priority for terrestrial carriers, especially in the context of converged networks, is to establish and guarantee dynamic SLAs (service level agreements) based on specific application needs. Voice applications, for example, must be protected from bandwidth degradation on a network shared by enterprise applications. Bandwidth must give way to high-priority applications such as video-conferencing while maintaining overall network performance. In a hybrid network environment, it is not uncommon for end users to experience robust quality of service (QoS) on a core terrestrial network but then incur voice and video packet loss on the satellite edge. The problem is that in a hybrid network, quality of service criteria are not universal but are set to specific segments or nodes of an overall network based on the unique characteristics that define them. To resolve this, satellite systems need to mirror the same application-level, dynamic quality of service criteria that govern terrestrial networks. Recent innovations in satellite technology development have addressed this challenge. The result is a single, consistent SLA that can manage and fuse together terrestrial, wireless and satellite networks. With this in place, end users can trust bandwidth-intensive and real-time applications – such as voice, video, point-of-service and online banking – to maintain terrestrial performance across a satellite network. 3 – Establishing end-to-end VPNs Another potential integration challenge is that many satellite networks cannot easily, or affordably, support Virtual Private Networks (VPNs). With satellites, the tendency is to define a distinct sub-segment as a single IP address space, which is not strictly a private network. To address this, satellite technology providers have developed a method to map Virtual Local Area Network (VLAN) tags directly to terrestrial networks. This ensures terrestrial data segregation on the satellite leg and enables sub-networks on a shared platform, which spreads the cost of satellite bandwidth. 4 – Ensuring total security Satellite networks have not always provided the same type of security as terrestrial networks – as they have not always transported sensitive data. Because of greater integration, technology leaders in the satellite industry have introduced developments such as two-way data encryption to match terrestrial standards. This is a critical step to encouraging organizations to trust critical applications and data on the satellite leg of an integrated network. As terrestrial carriers continue to improve data security, satellite technology leaders must incorporate the same innovations into their systems. 5 – Integrating network management and enabling straight-through provisioning An unconquered next-generation challenge is the integration of network management systems that monitor terrestrial, wireless and satellite networks. Currently, operators can leverage middleware to unite terrestrial Operational Support Systems (OSS) with satellite Network Management Systems (NMS), but a greater effort is underway to develop a common management system. This would create valuable business efficiencies, increase quality control and enable flow-through provisioning so customers can manage their network SLAs simply by accessing a Web portal. Seamless integration – a quick scenario Satellite and terrestrial communications can come together seamlessly to support both traditional satellite applications, such as remote connectivity and maritime broadband, and such emerging applications as business continuity. In the case of business continuity, satellite communications plays a critical role that lies beyond the functional capacity – rather than the geographical reach – of terrestrial networks. Terrestrial backup networks typically share the same local infrastructure as the primary network. When the primary network fails, the backup network often suffers from the same problem. Terrestrial backup networks also utilize lower speed lines that do not provide the same bandwidth capabilities as the primary network. So, if the primary network fails, a business or organization might not have adequate bandwidth on the backup network to support all of its applications. By contrast, a satellite network does not share local infrastructure, and is not subject to the same points of failure as the primary terrestrial network. And when the terrestrial network goes down and the satellite network takes over, a broadband experience is still in place to keep business running, not just flickering. When it is not being used as a back-up network, satellite connectivity can serve multiple needs, including multimedia distribution, digital signage and, of course, remote connectivity. Today, the terrestrial and satellite communications industries are travelling the same road, striving to meet a common set of end user demands. It is the role of satellite communications to extend the reach of terrestrial networks and drive the development of critical applications such as disaster recovery, business continuity, mobile connectivity, distance education and more. More than that, it is now the role of the satellite communications industry to help terrestrial carriers create an ultimate end user experience that is seamless and reliable.
