Example of SNMP protocol technology application (1)

In some current network architectures, we often use multiple protocols in combination. Next we will talk about the GPON Technology Based on the SNMP protocol. It may seem strange at first. It doesn't matter. Let's first take a look at the characteristics of this technology, and then analyze the protocol functions of this technology.

GPON technology is the latest generation of Broadband Passive Optical Integrated Access Technology Based on ITU-TG.984.x standards, it has many advantages such as high bandwidth, high efficiency, wide coverage, rich user interfaces, and is regarded by most operators as an ideal technology for broadband and integrated transformation of access network services. focus on GPON hardware, the physical specifications and hardware devices of the GPON system are discussed in detail. However, there is no good standard for how to assign software to the hardware, based on a series of GPON management operation specifications recommended by G984.4, this article describes the GPON management and control protocols in detail, and points out that management and control are the key to ensure the stable and secure operation of GPON, the overall structure of the network management system is proposed. Based on the analysis of the structure and functional modules of the GPON system, the network management of GPON and the relationship between management entities are described, the overall design of the software system is proposed, and the design of the SNMP-based GPON network management software system is discussed ｡

Overview of the overall structure of the GPON Network Management System

1. Overall structure of the GPON Network Management System

GPON Network is composed of Optical Line Termination (OLT), Optical Distribution Network (ODN), and Optical Network Unit (ONU) as shown in GPON Network Management Architecture 1, the management interface of the access network is located at the OLT end, while the optical network terminal devices of the access network are located at The ONU end, that is, in the GPON access system, the Network Management Information of optical network terminal devices is collected by the ONU end and sent to the management interface of the OLT end ｡

Figure 1 GPON Network Management System

2 G984.4 Protocol

Is the latest protocol in the G984 series. It specifies the ONT Management and Control Interface (OMCI) when the physical layer and the transport aggregation layer have been defined) this protocol mainly discusses the operation management and maintenance part of the GPON system, defines entities managed by the Management Information Library (MIB), these management entities are established in the optical network terminal (ONT) A model for information exchange between optical line Terminals (OLT). In addition, this Protocol includes the management of specific ONT messages, this makes coordination between multiple ONT and OLT possible [1]. It mainly includes research on OMCI frames and Research on MIB libraries unrelated to protocols. Figure 2 shows OMCI frames ｡

Figure 2 OMCI Frame

If the GEM header sends an ATM frame format, it is the ATM header. The message type (including set and get) is defined in this frame format ); device identifiers and message identifiers, which are mainly used to distinguish different managed entities of the defined protocol-independent mib library; the message content is used to fill in OMCI Frames Based on the Message Type of the managed entity, and OMCI trailer is mainly used to fill in the verification code ｡