Simple Transportation Management Framework

16.1 Introduction

The STMF specifies a set of rules and protocols which can be used to organize, describe and exchange transportation management information between transportation management applications and equipments. STMP is based on the Internet-standard Network Management Framework and its purpose is to provide a high-level compatibility, inter-operability, and maintenance of STMF. The STMF framework consists of the following four elements. The brief definitions of these elements are listed below and the detailed descriptions and relationships of these elements will be given in the following sections.

• • Management information base (MIB) (Perkins et al., 1997): A collection of management objects written in ASN.1 (Abstract Syntax Notation One) (Steedman et al., 1993; ITU-T X.680-X.690, 1994) notation, which is a standard and flexible notation that describes data structures for representing, encoding, transmitting, and decoding data.

• • Structure and identification of management information (SMI): The definition of how to create management objects and a hierarchical definition of nodes where management objects will be attached for unique identification.

• • Simple network management protocol (SNMP) (Stallings et al., 1993; Stallings et al., 1996; Feit et al., 1995): A communications protocol developed by the IETF for configuring and monitoring of network devices.

• • Simple transportation management protocol (STMP): A variation of SNMP developed by NEMA to address low-bandwidth communication links and real-time device monitoring. NEMA is the trade association of choice for the electrical manufacturing industry, and it provides a forum for the development of technical standards

16.1.1 Relationships of SMI, MIB, and ASN.1

SMI describes the common structures and identification schemes for the definition of management information. ASN.1 is used to specify SMI and it can be compiled by MIB compilers. To do so, SMI definitions (ASN.1 specifications) are included in a MIB module. As shown in Figure 1, the difference is made because SMI defines how to create managed objects and how to utilize ASN.1 in order to create and identify management information (MIB objects) within a tree-like structure. Management center uses Structure and Identification of Management Information to define MIB, then using BER or OER encoding scheme to generate SNMP or STMP.

Figure 1.

Relationships of SMI, MIB, and ASN.1