Media Converters in the MAN and Beyond

Most Local Area Networks have migrated to a Gigabit or at least a Fast Ethernet backbone with switched 10/100 connections to clients, printers and file servers. Fast on the inside, but slow on the outside, many U. S. businesses rely on copper T-1 and T-3 connections, or fiber ATM / SONET circuits for WAN connectivity. These connections were designed for voice but were never intended to handle the exponentially growth of Internet and data traffic, applications or the protocols typically used in today's LAN. What's more, provisioning and maintaining these circuits, or upgrading from a T-1 to a T-3 connection is an expensive and time-consuming proposition for both the service provider and the customer. It also requires significant capital investment at both the Point of Presence (POP) and the customer premises.  Ethernet is the dominant LAN protocol with the highest market penetration. Ethernet equipment is readily available at reasonable prices, and provides a migration path from 10 Mbps to 100 Mbps to Gigabit Ethernet. And with the 10, 40 and eventually, 100 Gigabit Ethernet standard, the application space for Ethernet will logically expand from the LAN to the MAN, and eventually to the WAN.


Media Converters are Flexible

Connecting copper switch ports to modular media converters for optical access enables service providers to fully benefit from the flexibility and distance offered by media converters. Media converters support multiple types of media from copper to multi-mode and single-mode fiber, and support 10 Mbps, 100 Mbps and Gigabit Ethernet.  Single-mode converters routinely cover distances of 20, 40 and 80 kilometers with 1310 nm optics, and even up to 130 kilometers with 1550 nm optics.

Media converters can also greatly enhance the consistency of service. With modular media converters, the network administrator can troubleshoot one circuit while the other customers' connections remain up and running. On the customer side, a standalone media converter can be used to provision an optical demarcation point, resulting in more cost savings and simplicity because the Telco router can be eliminated. Behind the media converter on the network edge, a Layer 2 LAN switch can be used to interconnect the public and private networks. Advanced protocols such as 802.1q, 802.1p, Quality of Service, and Network Address Translation can be handled at the POP switching router.

Benefits of Media Converters in the MAN

Tried and proven in the LAN, Ethernet is well positioned to become the protocol of choice for the transport of data, voice and video also outside the LAN.

Protocol transparency — service provider supplies the customer a standard Ethernet interface

Bit rate transparency — customer can connect to the service provider network at 10 Mbps, 100 Mbps or Gigabit Ethernet

Ethernet simplifies the network design — a traditional Telco router can be replaced with a remotely managed media converter

Customers can use the bandwidth they need, when they need it, without the wait associated with legacy services

Using media converters with Ethernet-based services minimizes the cost of provisioning and maintaining optical circuits