MAPOS Version 1 Assigned Numbers

This document describes the protocol parameters used in the Multiple Access Over SONET/SDH (MAPOS) version 1. MAPOS is a link layer protocol and provides multiple access capability over SONET/SDH links.

Multiple Access Protocol over SONET/SDH (MAPOS) is a high-speed link-layer protocol that provides multiple access capability over SONET(Synchronous Optical Network)/SDH(Synchronous Digital Hierarchy). Its frame format is based on the HDLC-like framing for PPP. A component called "Frame Switch" allows multiple nodes to be connected together in a star topology to form a LAN. Using long haul SONET/SDH links, the nodes on such a "SONET-LAN" can span over a wide geographical area. The Internet Protocol (IP) datagrams are transmitted in MAPOS HDLC frames . This document describes the protocol parameters used in MAPOS version 1 .

The MAPOS Version 1 Data Link Layer contains a 16 bit Protocol field to identify the the encapsulated protocol. The Protocol field is consistent with the ISO 3309 (HDLC) extension mechanism for address fields. All protocol numbers MUST be assigned such that the least significant bit of the most significant octet equals "0", and the least significant bit of the least significant octet equals "1". Assigned MAPOS Protocol Numbers Value (in hex) Protocol Name 0001-001F Not Used - reserved 0021 MAPOS Version 1 Internet Protocol Version 4 0023-FCFF Not Used - reserved FE01 MAPOS Version 1 Address Resolution Protocol (ARP) FE03 MAPOS Version 1 Node Switch Protocol (NSP) FE05 MAPOS Version 1 Switch Switch Protocol (SSP) FE07-FEFF Not Used - reserved

The authors would like to acknowledge the contributions and thoughtful suggestions of John P. Mullaney, Clark Bremer, Masayuki Kobayashi, Paul Francis, Toshiaki Yoshida, and Takahiro Sajima.