Ethernet Private Line Service

Sharing SONET channels over a shared SONET infrastructure is known as an Ethernet Private Line. Encapsulated in SONET payloads Ethernet frames are at the customer premises and transported through SONET infrastructure to another customer site.

Ethernet Private Line services include:

  • Ethernet over DS3
  •  Ethernet over T1
  • 10 Mbps Ethernet (10BaseT) over SONET
  • Full rate Fast Ethernet, Fast Ethernet over SONET and partial rate Fast Ethernet
  • Gigabit Ethernet over SONET, including full rate (1000 Mbps) Gigabit Ethernet and five partial rates (50, 150, 300, 450, and 600 Mbps)

SONET Payloads

Supporting a data rate of 49.5 Mb/s, SONET payload is designated as STS-1. Ethernet frames at 10 Mb/s, partial rate fast Ethernet frames of 50 Mb/s and the lowest partial rate of Gigabit Ethernet frames are put into STS-1 payloads. These smaller payloads can be put together to make larger payloads. Up to three STS-1 payloads can be concentrated forming a STS-3c payload, which can be used to carry full rate fast Ethernet. 600 Mb/s of gigabit Ethernet can be concentrated with twelve STS-1 payloads.

Virtual Concatenation

Virtual connections create situations where STS-1 payloads can be linked at end points, but handled separately through the network. To form a STS-1-3v payload, three STS-1’s must be connected. This will carry up to 150 Mb/s of Gigabit Ethernet. Other partial rate gigabit Ethernet services are done in six, nine, twelve and twenty-one STS-1 payloads.

Customer Interfaces

Based on the 10BASE-T standard, 10 Mb/s Ethernet service is an electrical customer. 10BASE-T uses two unshielded twisted pairs with a length of up to 100meters long. Customer interface is based on 100BASE-TX technology to bring gigabit Ethernet service for optical interfaces for customer equipment. Gigabit Ethernet services are either on the 1000BASE-SX, where multi-mode fibers are used, or on the 1000BASE-LX, where a single mode fiber is used. Distance limitations on optical interfaces generally are not problems or Ethernet Private Line Services.

Alternate Handoff

Customers can use a SONET rather than a native mode handoff can be used at one end. SONET handoffs would be optical with a standard interface like an OC-3 or OC-12 interface.


Near perfect quality of service and high resiliency are delivered through an Ethernet Private Line Service. Less expensive than traditional private line, Ethernet Private Line services deliver better wavelength services. LAN’s can create interconnections and extensions to SONET rings can be provided to help Ethernet Private line services.


Ethernet provides a great high quality connection with a low cost that is great for almost anything your business needs to do. Through replacing Frame Relay and ATM services, you can reduce costs and simplify network administration over the MAN and WAN networks with Ethernet services.

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