Zte Ptn 6z5a3s

ZXCTN 6000 Products Basic Working Principles Technical Specifications

Operator Logo

ZXCTN 6000 Products Basic Working Principles Technical Specifications

ZXCTN 6000 Products Basic Working Principles Technical Specifications

ZXCTN 6000 Products Technical Specifications Version

Date

V1.00

2009-03-11

Author

Basic

Approved By

Working

Principles

Remarks Not open to the Third Party

© 2009 ZTE Corporation. All rights reserved. ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used without the prior written permission of ZTE. Due to update and improvement of ZTE products and technologies, information in this document is subjected to change without notice.

ZXCTN 6000 Products Basic Working Principles Technical Specifications

TABLE OF CONTENTS 1

Preface ........................................................................................................................ 1

2 2.1 2.2

A Brief Introduction to the Technology ................................................................... 1 Basic Principle of System Framework ......................................................................... 2 Basic Procedure of Service Processing ...................................................................... 3

3 3.1 3.2

Key Technology.......................................................................................................... 4 Basic Principle of OAM ................................................................................................ 4 Basic Principle of Protection ........................................................................................ 6

4

Abbreviations ............................................................................................................. 9

5

Reference .................................................................................................................. 10

ZXCTN 6000 Products Basic Working Principles Technical Specifications

FIGURES Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

System framework ......................................................................................................... 2 Procedure of multi-service bearing ................................................................................ 3 Hierarchical OAM........................................................................................................... 4 Linear 1+1 protection ..................................................................................................... 6 Linear 1:1 protection ...................................................................................................... 7 Ring Wrapping protection .............................................................................................. 8

ZXCTN 6000 Products Basic Working Principles Technical Specifications

1

Preface ZXCTN 6000 series is the new generation metro area optical network product of ZTE oriented to packet delivery. It adopts the system architecture with packet switching as kernel. Adopting PWE3 (Pseudo-wire Emulation Edge-to-Edge) it realizes bearing of multiple services. Via MPLS forwarding technology with delivery features, working with carrier-class OAM and protection switchover mechanism, it realizes carrier-class delivery of packet of multiple services. It also provides high-precisely clock and time transmission to meet the needs of 3G Backhaul market. The product have the following models according to their service processing capability in an ascending sequence: ZXCTN 6100：1U Pizza Box product oriented to access layer. With 3Gbps processing capability, it adopts the structure of SMB master card and 2 expanded cards. it provides low-cost packet and TDM service access. Its master card can directly provide common FE, GE service interfaces and abundant auxiliary interfaces concerned telecom management and clock (such as Qx, LCT, Alarm, 2Mbits and 1pps&TOD). Via the 2 expanded cards it can provide expansion of interfaces such as TDM E1, IMA E1, FE, GE, and STM-1. the equipment works mainly to achieve network protection without providing hardware card-level protection. ZXCTN 6200：With 3U height and 20-40Gbps processing capability, it is oriented to products with hardware card-level protection at access and aggregation edge layer. It adopts 1+1 redundancy structure for power supply and MSC. Providing 4 interface card slots, it s various interfaces of FE, GE, 10GE, TDM E1, IMA E1 and STM-1/4. Its interface cards are compatible with those of ZXCTN 6300. ZXCTN 6300：With 8U height and 88Gbps processing capability, it is oriented to products with hardware card-level protection and E1 1:N TPS protection at aggregation layer. It adopts 1+1 redundancy structure for power supply and MSC. Providing 6 lowspeed interface card slots and 4 high-speed interface card slots, it s various interfaces of FE, GE, 10GE, TDM E1, IMA E1 and STM-1/4. It also provides 2 extra circuit branch interface slots to realize two groups of E1 1:2 protection.

2

A Brief Introduction to the Technology ZXCTN 6000 series adopts T-MPLS/MPLS-TP technology oriented to delivery. Integrated with the features of data and transmission, adopting the architecture with packet switching as kernel, working with connection-oriented service delivery technology, it solves the problem that traditional MSTP network cannot implement bandwidth multiplexing when it carries packet services. At the same time it guarantees end-to-end delivery feature of service, realizes end-to-end monitoring and complete protection of packet network. At management plane It inherits the tradition of delivery-oriented carrierclass network management system. It s network management of multi-service bearing and expansion of control plane to meet the needs of OPEX reduction.

ZTE Confidential Proprietary

© 2009 ZTE Corporation. All rights reserved.

1

ZXCTN 6000 Products Basic Working Principles Technical Specifications

2.1

Basic Principle of System Framework The system architectures for ZXCTN 6100, 6200 and 6300 are basically similar. They all adopt a centralized service processing structure. Their MSC or master card implements MPLS forwarding plane functions and network element management, clock and time processing. Their interface cards or expanded cards mainly complete auxiliary functions such as interface switch, PWE3 processing, 1588 and OAM. By a proper layout of functions, they avoid possible congestions in internal service processing, meet wirespeed forwarding requirements, and greatly reduce power consumption. Figure1 I is a diagram showing the system framework of ZXCTN 6000:

Figure 1

System framework

MSC The service forwarding core of the system is integrated service processing and scheduling unit of MSC, which adopts network processor and private ASIC to realize Ethernet service processing, L2/L3 switching, MPLS switching, and service QoS control. Forwarding route can be decided based on message carried by ingress packet. L2/L3 control protocol, OAM, IEEE1588 packets can be identified and forwarded to MSC U, 1588 and OAM unit for protocol exchange and calculation. Service packets go through the procedure of traffic classification, traffic control, learning and search, switching, and queue management before they are forwarded to corresponding service ports, where they are integratedly processed and buffered. Packet forwarding rate is improved as much as possible to avoid congestion inside equipment. As system software carrier, MSC U sub-system work with software system to realize L2/L3 control protocols such as MSTP, LA, OSPF, IGMP Snooping, SSM, and BMC; and to complete key functions of service-concerned T-MPLS/MPLS-TP alarm, performance management, related abnormality monitoring and multi-layer protection switch. It also implements management plane functions, management of each interface

ZXCTN 6000 Products Basic Working Principles Technical Specifications

card, collection and storage of alarm performance, resolution of network management configuration commands, and storage of configuration data. MSC sub-system usually s 1+1 and M:N redundancy protection. It avoids equipment failure caused by key unit fault through card-level protection. ZTE ZXCTN 6200 and 6300 1+1 protection, graceful restart and avoid the impact of MSC switch on service and protocol as much as possible. Interface unit Each interface card mainly implements expansion of service interfaces of FE optical/electrical, GE optical/electrical, 10GE optical, CES E1, IMA E1, Ch. STM-1/4, Ch. POS STM-1/4, and ATM STM-1. For FE/GE/10GE Ethernet cards, interface cards need to implement resume and delivery of synchronous Ethernet clock, and improve time transport precision and service performance statistics precision. Interface card needs to take IEEE 1588 PTP time stamp processing and performance monitoring of LM（Loss Measure）and DM （Delay Measure）services at the nearest interface side; so as to avoid the impact of unpredictable buffer depth of service processing unit on ns level precision needed by PTP time stamp. Error of LM and DM statistics can also be avoided. For ATM and TDM cards such as E1 and STM-1/4, besides implementing resume and delivery of interface clock, interface cards mainly implement PWE3 processing. They can encapsulate ATM cell into pseudo-wire by cascading based on VPI/VCI, and implement ATM VPI/VCI switching to avoid VPI/VCI conflict at different ports or PW. TDM cards need to have slicing processing first. They extract TDM code stream with 125us as unit based on ’s configuration, and encapsulate it to the corresponding PW based on port and time slot configuration. Reversely, when PWE3 packets are received, besides packet buffering of a certain depth should be implemented to counteract network delay and jitter, interface clock recovery of self-adaption and clock recovery need to be implemented for interface side to provide TDM code stream of correct frequency output.

2.2

Basic Procedure of Service Processing ZXCTN 6000 s access of packet service and TDM service. It adopts E-LINE, ELAN, and E-TREE service management defined by MEF and ITU-T to provide Ethernet linear, switching and aggregation services. Figure2 is a diagram showing service procedure of ZXCTN 6000:

Figure 2

Procedure of multi-service bearing

ZTE Confidential Proprietary

© 2009 ZTE Corporation. All rights reserved.

3

ZXCTN 6000 Products Basic Working Principles Technical Specifications

Ethernet UNI<->NNI: implement E-LINE, E-LAN and E-TREE Ethernet service processing; complete adding, modification or peel-off of CE-VLAN; fulfil service identification to implement CAC control, priority identification and traffic control. MAC address for switching and aggregation services are learned and searched in VPN domain. Packets with forwarding route determined is implemented PWE3 encapsulation and bound to LSP tunnel and sent to the designated port. At the same time OAM alarm and performance monitoring are implemented based on PW, tunnel and section-layer. TDM E1 / Ch. STM-1<->NNI: implement E1 cell slicing on uplink, multi-cell cascading processing, and implement PWE3 encapsulation before binding them to LSP tunnel. On downlink, resolve PW from LSP before disassemble cascading cells based on sequence number in PWE3, and send them to receiver buffer to decrease delay and jitter of network side. Clock at outgoing port can implement self-adaptive recovery based on buffer depth and packet receiving or implement E1 clock retiming by directly using system clock. At network side OAM alarm and performance monitoring can be implemented based on PW, tunnel and section-layer. ATM<->NNI: implement ATM cell recovery on uplink. Complete VPI/VCI exchange based on network management configuration, multi-cell cascading processing, and PWE3 encapsulation before binding them to LSP tunnel. On downlink, resolve PW from LSP before disassemble cascading cells based on sequence number in PWE3. complete VPI/VCI exchange on downlink and implement ATM encapsulation and sending again.

3

Key Technology

3.1

Basic Principle of OAM By T-MPLS/MPLS-TP OAM ing hierarchy, ZXCTN 6000 can realize alarm and performance monitoring of end-to-end service, LSP tunnel and section-layer between two adjacent points. The hierarchical OAM is shown in Figure 3:

Figure 3

Hierarchical OAM

ZXCTN 6000 Products Basic Working Principles Technical Specifications

Service connection between service source and sink can be checked by PW layer monitoring. Tunnel protection switchover can be realized by network checking via tunnel layer monitoring. Check physical link by monitoring of section-layer to improve linear protection switchover speed and to initiate ring protection switchover. The hierarchical OAM of T-MPLS/MPLS-TP covers: •

PW layer: providing T-MPLS/MPLS-TP transport network service. One PW layer OAM connection is used to transport one client service entity (including a single customer service or a group of customer service).

•

Tunnel layer: providing transport network Trunk. One tunnel connection transport one or multiple TMC signals at the edge of tunnel domain.

•

Section-layer: section-layer OAM provides OAM monitoring between two adjacent T-MPLS/MPLS-TP nodes. Since section-layer OAM instance and service layer route are one to one, no label is needed and service layer route must be point to point.

Key OAM functions include: •

Continuity and Connectivity Check (CC): pre-activated OAM, checking whether the connection is normal. Fast CC can act as checking evidence for route switch. Slow CC is only used to check service connection and interruption.

•

Alarm Indication Signal (AIS): maintenance signal, used to notify service layer route failure signal to client layer. If section-level SF is found, tunnel layer AIS needs to be inserted.

•

Remote Defect Indication (RDI): maintenance signal, used to a remote defect indication signal to remote when the near-end detects a failure.

•

LB (Loopback): MEP is the initiating point of packet request by loopback. The implementation point of loopback could be MEP or MIP. It is OAM on demand.

•

LM(Frame Loss Measurement): used to measure the frame loss ratio of single-way or bi-directional from a MEP to another MEP.

ZTE Confidential Proprietary

© 2009 ZTE Corporation. All rights reserved.

5

ZXCTN 6000 Products Basic Working Principles Technical Specifications

3.2

•

DM （ Packet Delay and Packet Delay Variation Measurements (DM): used to measure the single-way delay and delay change from MEP A to MEP B (needs to IEEE1588), or bi-directional delay and delay change between MEP A and MEP B.

•

Automatic Protection Switching (APS) : used to send and protect relevant APS frame.

•

Synchronization Status Message (SSM) : defined by G.8261 to send SSM frame; used for clock protection of synchronous Ethernet.

Basic Principle of Protection T-MPLS/MPLS-TP network protection covers linear protection and ring protection mechanisms. Linear protection includes 1+1 route protection, 1:1 route protection and SNC 1+1, SNC 1:1 protection, which share the basically identical protection principles. Basic principle for linear 1+1 protection: •

Each working connection has a private protection connection. Working connection and protection connections are bridged at source of the protected domain. Source services are sent to the sink of protected domain via working and protection connections at the same time. At the sink services on working or protection connections are selected based on fast CC connection check. To avoid single-point failure on network, working and protection connections should be configured with separated routes.

•

Linear 1+1 protection is single-way switchover. That is to say, only the impacted connection direction is switched to protection route. The selector on two ends are independent. 1+1 T-MPLS route protection operation could be revertive or nonrevertive.

Figure 4

Linear 1+1 protection

ZXCTN 6000 Products Basic Working Principles Technical Specifications

Basic principle of linear 1:1 protection: •

Each working connection has a private protection connection. The protected services are transported by working or protection connections. Selection between working and protection connections are made based on CC connection check by APS. To avoid single-point failure on network, working and protection connections should be configured with separated routes.

•

1:1 T-MPLS route protection is bi-directional switchover. That is to say, both the impacted and unimpacted connection directions are switched to protection route. Bidirectional switchover needs Automatic Protection Switch protocol (APS) to coordinate the connecting two ends. Bi-directional 1:1 T-MPLS route protection operation is revertive.

•

1:1 protection features high bandwidth and multiplexing ratio, which can avoid waste of protection link bandwidth.

Figure 5

Linear 1:1 protection

ZTE Confidential Proprietary

© 2009 ZTE Corporation. All rights reserved.

7

ZXCTN 6000 Products Basic Working Principles Technical Specifications

Since MPLS-TP ring protection standards are still under research, here we just give a description of basic principle of ring protection of the mature T-MPLS Wrapping protection: •

Ring protection takes action based on service layer failure, TMS section-layer failure or performance degrading.

•

When a node on network detects a network failure, the adjacent node send switching request to neighbor nodes via APS protocol. When a node detects failure or receives switching request, the common services forwarded to the failed node will be switched to the other direction (far away from the failed node). When network fails or APS protocol request disappears, services will be returned to the original route.

Figure 6

Ring Wrapping protection

ZXCTN 6000 Products Basic Working Principles Technical Specifications

4

Abbreviations <===============Sample begins========================== Abbreviations

Full form

GSM

Global System for Mobile communications

EDGE

Enhanced Data rates for GSM Evolution

WCDMA

Wideband Code Division Multiple Access

CN

Core Network

GERAN

GSM Edge Radio Access Network

ZTE Confidential Proprietary

© 2009 ZTE Corporation. All rights reserved.

9

ZXCTN 6000 Products Basic Working Principles Technical Specifications

Abbreviations

Full form

UTRAN

UMTS Terrestrial Radio Access Network

MS/UE

Mobile Station/ Equipment

BSC

Base Station Controller

RNC

Radio Network Controller

BTS

Base Transceiver Station

SDR

Software Defined Radio

CDMA2000

Code Division Multiple Access 2000

WiMAX

Worldwide Interoperability for Microwave Access

MicroTCA

Micro Telecommunications Computing Architecture

eEDGE

Enhanced EDGE

SDH

Synchronous Digital Hierarchy

CAPEX

Capital Expenditure

OPEX

Operation Expenditure

RF

Radio Frequency

LTE

Long Term Evolution

RI

Common Public Radio Interface

BBU

Base Band processing Unit

RRU

Remote Radio Unit

FP

Frame Protocol

<===============Sample ends==========================>

5

Reference < All reference involved in this technical specification> <===============Sample begins========================== List of reference: ITU-T Recommendation Y.1710(2002), "Requirements for OAM Functionality for MPLS Networks”. ITU-T Recommendation Y.1711(2004), "Operation & Maintenance mechanism for MPLS networks”. ===============Sample ends===========================>