• Planning Horizon: Optical transmission comes under infrastructure equipment and so service providers should look at 3–5 years period before opting for it. Service providers should also have a complete roadmap of the kind of services that they plan to provide over a period of time. This helps service providers in getting the best equipment and also protecting future investments as they move to address the future requirements of their customers. Service providers should closely associate with vendors so that there is uniformity between services launched and availability of equipment.
• Understand Your Requirements: Service providers who plan to deploy transmission equipment should first evaluate their networks. They should first decide on whether they plan to do the deployment on their own or they plan to take the help of equipment manufacturers. Second, they should be clear as to what to deploy as vague requirement can lead to additional costs, thereby increasing the capital expenditure.
• End-to-end Network Management: With networks becoming more complicated with triple play—voice, video, and data—service providers are finding it increasingly difficult to manage the network due to different applications and increase in number of interfaces. Vendors who provide end-to-end management will have an advantage as one need not worry about interfacing with other elements. One should see whether vendors can provide element management or complete network management. One should also see whether billing-related things are also taken care of, as long-distance carriers are also providing bandwidth to other carriers.
• Redundancy, Robustness, and Protection: The vendor should provide both equipment and network protection. Service providers should check whether protection mechanisms are built in the product or they have to make additional investments. With subscribers increasing at a fast pace, the network should be able to support it whether in centralized mode or in distribution mode. There should be a reduction in set-up time for the provisioning of new services. With increase in number of services, data and optics integration should work in tandem, because storage will become very important with more and more applications.

The increase in network size should also result in support and service levels from the vendor so that the network is robust, reliable and highly redundant.

• Scalability and Modularity: With subscribers and traffic increasing at a fast pace one should see whether the existing system is scalable and modular to meet future demand. It should not only be scalable in terms of number of subscribers and traffic, but also in terms of applications.

• Flexibility: The network should be designed in such a way that even if more than one ring goes down it should still work so that the network can be routed even when part of the network is down. Flexibility should be in terms of cross connection, types of interfaces/services, support technology and application revolution. In terms of interfaces, the equipment should provide TDM capabilities—E1, DS3, STM-1, STM-4, STM-16, and STM-64; emerging technologies like ESCON and FICON, and IP technologies—ATM, IP, MPLS< Ethernet, and Gigabit Ethernet. All these features will vary depending on metro, regional, and backbone infrastructure.