 | Issue: | North America 2009 |
| Article no.: | 7 | |
| Topic: | POTS for data-intensive services | |
| Author: | Noam Lotan | |
| Title: | President & CEO, | |
| Organisation: | MRV Communications Inc. | |
| PDF size: | 228KB |
About author
Noam Lotan is the President and CEO of MRV Communications. Until assuming his current post, Mr Lotan was MRV’s Chief Financial Officer. Earlier, Mr Lotan served as Managing Director of Fibronics (UK) Ltd, a manufacturer of fibre optic communication networks; later when purchased by MRV, Mr Lotan assumed the post of Director of European Operations for Fibronics. Mr Lotan held a variety of sales and marketing positions with Fibronics and Hewlett-Packard. He is also a Director for Capstone Turbine Corporation, Noam Lotan holds a Bachelor of Science degree in Electrical Engineering from the Technion, the Israel Institute of Technology and a Master’s degree in Business Administration from INSEAD, the European Institute of Business Administration, Fontainebleau, France.
Article abstract
‘POTS’, the old acronym for plain old telephone service has a new meaning – packet optical transport services. The growth of POTS is driven by the insatiable demand for broadband-dependent content-rich, multimedia applications such as entertainment and video services and the operating companies’ need to upgrade network capacity without cutting too heavily into profits. POTS enhances capacity and efficiency and, unlike traditional SONET/SDH networks, POTS not only handles10G Ethernet, but can be dynamically and remotely reconfigured to meet user needs.
Full Article
In the telecommunications industry, the acronym POTS will soon no longer conjure memories of ‘Plain Old Telephone Service’ and voice-only networks of the past. The new POTS stands for packet optical transport services, a new class of data-aware optical networking equipment. Although it may take time for the migration from today’s SONET/SDH networks to POTS networks, industry analysts agree that POTS will be a necessary component for the high-bandwidth, high-quality and cost-effective networks of the video and real-time data era that we are now living in. Over the past decade, demand for data services has increased with the explosion of technologies such as DSL, fibre optic access and broadband wireless networks. Additionally, today’s mobile phones are now handling as much data as PCs had in the past, with the ability to process voice, data and video. To handle the demands of these services, all of these technologies require a network infrastructure that delivers high performance and has the provisioning flexibility operators need. Today’s optical backbone networks rely on SONET/SDH to transport high-speed data. However, the explosion of data services is beyond what these circuit-switched networks can cost-effectively deliver. This results in considerably higher capital and operational expenses for service providers when compared to the scalability and cost effectiveness of Internet Protocol (IP) networks. SONET/SDH is a less cost-effective solution because it cannot provision maximized bandwidth and cannot be scaled to fit changing network demands. Enter POTS – the combination of packet and optical. While is the exact definition of POTS is still being worked out and the equipment and vendor taxonomies are still in flux, product and technology definitions are generally known. The benefits of these networks, however, are well known, and are driving network growth even though service providers must be very choosy about their CAPEX spending. According to a report by Heavy Reading, the POTS market should grow from its current small base to reach US$2.8 billion in sales in 2012 according to forecasts that assume a modest annual growth rate of 4.8 per cent CAGR (compound annual growth rate) for worldwide optical transport revenue. The report also indicated that the move from SONET/SDH would continue, and that it would decline at a rapid pace. Why POTS? As innovative consumer services increase demands on telecom networks, operators will look for solutions that meet these new demands while maintaining cost-effective operations. One area where this is most pronounced is in the area of video and entertainment delivery. From IPTV to mobile TV to YouTube! carriers are being called on to deliver more real-time video than ever before. POTS is very useful in the deployment of content-rich, multimedia applications such as entertainment and video services delivered through the Internet or mobile network. One issue with these services is the need for high quality, uninterrupted data speeds. With POTS, the optical transport can handle high-speed data transfer rates providing the highest quality available for these services. POTS enhances the backhaul capacity, efficiency and service delivery of the network. POTS also enhances services within the mobile network. POTS will provide a smooth transition for the telecom operators who are upgrading their backhaul networks to support the move to 4G/LTE services. POTS allows for greater flexibility and reliability for mobile traffic, by offering a solution that allows for scaling of bandwidth when necessary. Many operators now offer triple play services such as Internet, TV and phone, and POTS can provide the operational consistency and efficiency these bundled services require. POTS supports the full-rate packet traffic needed for high-speed Internet and video services. A secondary benefit of POTS that goes beyond high-speed data networking is the service provisioning flexibility and speed provided by these networks. In a SONET network, service provisioning can take weeks or months because site visits have to be scheduled and changes to network cabling – ranging from laying new cable to reconfiguring cabling in wiring closets and switching centres – may be required. The ability to offer services on demand, or even temporary services, is one of the requirements of the new world of data networking. Customers may want high-speed data services for a short period, like during a big promotion on their Website, or during parts of the day when they know they need higher bandwidth, like overnight backups. Business users, in particular, expect the carrier to be able to deploy new services in a matter of hours or days. POTS network technologies POTS is a new category of optical transport system; it is based on three key optical technologies: generalized multi-protocol label switching (GMPLS), wavelength division multiplexing (WDM) and reconfigurable optical add-drop multiplexer (ROADM). POTS also supports Layer 2-4 connection-oriented Ethernet switching support in a single chassis. Some systems also provide SONET/SDH ADM connectivity for legacy network interconnect. That is a tall order because it combines legacy network support with support for several still evolving technologies. GMPLS is the latest version of the MPLS protocol that is very widely used in networks today to provide quality of service. With GMPLS, however, equipment manufacturers can completely separate the control and data planes of a network switch/ router to support network switching for time, wavelength, and space switching as well as for packet switching. With GMPLS, a switch can map packets to light waves and deliver flexible switching on layer 2, 3 or 4 of the IP protocol stack, enabling a seamless interconnection and convergence of new and legacy networks. WDM is today’s state of the art technology for high-speed optical networks; it currently provides speeds of 40Gbps and speeds of up to 100Gbps are on the horizon. WDM multiplexes multiple optical carrier signals on a single optical fibre by using different wavelengths to carry each signal. This multiplies capacity and enables bidirectional communications over a single strand of fibre. ROADM is a key optical technology for POTS; it offers a cost-effective way to remotely add or drop a service to meet customer demand without manually changing the cabling. ROADM is an optical add-drop multiplexer that remotely switches WDM traffic at the wavelength layer so individual, or multiple, data channels (wavelengths) can be added and/or dropped from a transport fibre at each node. Putting it together What does a POTS network look like after putting together all of these technologies? The POTS network starts at the edge IP demarcation switches. Ideally, these offer up to 10G Ethernet switching for customer networks and comprehensive operations, administration and maintenance (OAM) to reduce operations costs. These ‘demarc’ switches need flexible connectivity to the carrier network, via either WDM or 10Gbps IP switching. Aggregation switches are the next key point, because this is where a lot of intelligence for making service-provisioning decisions is located. The ideal aggregation switch will have IP switching to connect to the demarc switches and, connecting to the carrier, will have WDM connectivity with GMPLS for the service provisioning flexibility. At the transport part of the network, data is fed into a POTS-enabled WDM platform where the ROADM capability delivers the flexibility to reconfigure services at each hub of a long-distance transport ring. So with ROADM technology, the carrier is able to redeploy the physical interconnection from a central management location. Looking forward to POTS Today’s service providers are faced with the task of expanding their networks to provide advanced data services while maintaining the quality of service demanded by users. POTS allows network operators to evolve their networks easily to deliver new services. With POTS technology, operators can maintain the operational consistency and efficiency required to maintain services while staying ahead of the demand for advancing technologies.
