Overview
The Cortina Systems
Optical Network (GEPON or EPON) Optical Network
Unit (ONU) chip (CS8016 ONU) implements functions
for Customer Premise Equipment (CPE). Equipment
vendors can build a complete CPE bo x with the
CS8016 ONU and add extr a features using the
embedded CPU, spare Flash memory space, external
SRAM interface, and flexible GPIO bus.
The CS8016 ONU is an IEEE 802.3ah* standard-
compliant device. It allows equipment v endors and
network operators to build an EPON system mixing
and matching with different IEEE 802.3ah* compliant
devices. The standard-compliant solution enables
network operators to preserve their investment and
save their cost in the long run.
The CS8016 ONU works in conjunction with the
Cortina Systems
(CS8021 OLT) and the Intelligent R eal-Time Operating
System (iROS). The iROS is a distributed and scalable
operating system that runs on the CS8016 ONU ,
CS8021 OLT, and the system control plane to control
Copyright © 2005 - 2008 Cortina Systems, Inc.
Cortina Systems
Typical System Application Diagram
PON
®
CS8021 Optical Line Terminal (OLT)
®
CS8016 Gigabit Ethernet P assive
Management
TM
Optical Xcvr
Typical System Application Diagr am
PHY
FE
®
CS8016 EPON Optical Network Unit Chip
EPON ONU
GPIO bus & devices (Optional)
Flash
CS8016
and manage the EPON system. This architecture
provides a wide r ange of Quality-of-Service (QoS) and
Traffic Management services. They ensure the
bandwidth, delay, and jitter requirement for each ONU
are met according to the tr affic profile extracted from
the Service Level Agreement (SLA).
The CS8021 OLT and CS8016 ONU also pro vide
differentiated services for v arious categories of tr affic to
ensure preferential treatment to high priority tr affic
such as voice and video. To meet these goals, the iROS
traffic management feature-set pro vides APIs to
configure five major QoS components in the CS8021
OLT and CS8016 ONU – Dynamic Bandwidth Allocation
(DBA) algorithm, traffic classification, traffic
conditioning (shaping, policing, and marking), queue
scheduling, and buffer management. All these
components work together to pro vide SLA-based QoS
guarantees, fair allocation of ex cess bandwidth, and
prioritization of user tr affic across ONUs and OLTs in the
EPON system, in both upstream and downstream
directions.
(Optional)
SRAM
EEPROM
Copper
PHY
Product Brief
UNI
Product Brief Number: 400047-3.0