What is the WAN Interface Sublayer (WIS)?

Introduction

In high-speed networking, the WAN Interface Sublayer (WIS) plays a pivotal role in adapting 10 Gigabit Ethernet (10GbE) for wide area network (WAN) environments. By enabling compatibility with SONET/SDH networks, WIS allows Ethernet frames to be transmitted efficiently over long-distance carrier infrastructures. Understanding WIS is essential for network engineers, IT professionals, and enterprises that deploy 10GbE networks with WAN requirements.

LINK-PP’s 10G optical modules, such as 10GBASE-LR SFP+, fully support WIS functionality, ensuring seamless operation in both LAN and WAN PHY modes.

What is the WAN Interface Sublayer (WIS)?

The WAN Interface Sublayer (WIS) is a functional layer defined in the IEEE 802.3ae standard for 10 Gigabit Ethernet. Its primary purpose is to adapt standard Ethernet frames for transmission over SONET/SDH networks, which operate at slightly lower line rates than LAN PHY.

Key Functions of WIS:

  1. Frame Encapsulation: WIS encapsulates standard Ethernet frames into a SONET/SDH-compatible format, enabling smooth interoperability with carrier networks.

  2. Data Rate Adaptation: While LAN PHY runs at 10.3125 Gbps, WIS adjusts the data rate to 9.953 Gbps, aligning with OC-192/STM-64 standards.

  3. Error Detection: Provides additional integrity checks to ensure data consistency during long-distance transmission.

  4. Compatibility: Bridges the gap between enterprise LAN environments and WAN infrastructures, maintaining reliable 10GbE connectivity.

WAN Interface Sublayer (WIS)

WIS in WAN PHY Applications

WAN PHY is designed for Ethernet deployment over carrier networks. WIS is a critical component of WAN PHY, enabling Ethernet frames to traverse SONET/SDH links.

Benefits of WIS in WAN PHY:

  • Carrier Network Integration: Ensures 10GbE signals can be transmitted over existing telecommunication backbones.

  • Long-Distance Transmission: Supports connections spanning tens of kilometers while preserving signal integrity.

  • Flexible Deployment: Works with LINK-PP optical modules to switch between LAN PHY and WAN PHY as needed.

LINK-PP 10GBASE-LR SFP+ modules implement WIS, making them ideal for enterprise-to-carrier connections, metro networks, and WAN deployments requiring both high performance and compatibility.

Technical Overview

Feature

Description

Standard

IEEE 802.3ae

Data Rate (LAN PHY)

10.3125 Gbps

Data Rate (WAN PHY with WIS)

9.953 Gbps (OC-192/STM-64 alignment)

Function

Encapsulation of Ethernet frames for SONET/SDH

Application

WAN PHY, carrier networks, metro, and long-distance links

Conclusion

The WAN Interface Sublayer (WIS) is a crucial component for extending 10 Gigabit Ethernet into wide-area networks. By enabling LAN-to-WAN adaptation, frame encapsulation, and rate alignment with SONET/SDH, WIS ensures reliable, high-speed data transmission across carrier networks.

LINK-PP’s 10G optical modules support WIS and WAN PHY modes, providing network engineers with the flexibility to deploy 10GbE links in both local and wide area environments.