Connectivity and Protocols - The Technical Side: OSI and TCP/IP, FTP, TELNET, SR, ILL, Update
Liv A. Holm · IFLA Journal · 1994
Networks are modeled in layers. For each layer, one or more services are defined, and for each service a protocol is specified. Two OSI application level protocols have been defined for library services: SR and ILL. The underlying layers are supposed to be OSI services, but some implementations are using TCP/IP, and some are using a mixture of OSI and TCP/IP. The systems based directly on TCP/IP can not communicate with those based purely on OSI. The articles discusses the pros and cons for choosing OSI or TCP/IP. Gateways between the OSI and TCP/IP networks are needed. The ISO protocol SR and the ANSO protocol Z39.50 are both search and retrieve protocols. The SR is almost a subset of the Z39.50, but they may become identical in the future. There is only one protocol for interlibrary loan, the ISO ILL protocol. It covers three models of interlibrary loan and all services connected with ILL. Other services such as Explain, Scan and Update are presently being discussed in ISO TC 46. The library community also needs network services such as file transfer, remote login, directories, and electronic mail. These are discussed in the paper