RFC 1103 (rfc1103) - Page 2 of 9
Proposed standard for the transmission of IP datagrams over FDDI Networks
Alternative Format: Original Text Document
RFC 1103 IP Datagrams over FDDI Networks June 1989 toward International Standardization for Media Access Control (MAC) [4], Physical Layer Protocol (PHY) [5], Physical Layer Medium Dependent (PMD) [6], and Station Management (SMT) [7]. The family of FDDI standards corresponds to the IEEE 802 MAC layer standards [8, 9, 10]. The remainder of the Data Link Service is provided by the IEEE 802.2 Logical Link Control (LLC) service [11]. The resulting stack of services appears as follows: +-------------+ | IP/ARP | +-------------+ | 802.2 LLC | +-------------+ | FDDI MAC | +-------------+ | FDDI PHY | +-------------+ | FDDI PMD | +-------------+ This memo describes the use of IP and ARP in this environment. At this time, it is not necessary that the use of IP and ARP be consistent between FDDI and IEEE 802 networks, but it is the intent of this memo not to preclude Data Link Layer interoperability at such time as the standards define it. Packet Format IP datagrams and ARP requests and replies sent on FDDI networks must be encapsulated within the 802.2 LLC and Sub-Network Access Protocol (SNAP) data link layers and the FDDI MAC and physical layers. The SNAP must be used with an Organization Code indicating that the SNAP header contains the EtherType code (as listed in Assigned Numbers [12]). 802.2 LLC Type 1 communication (which must be implemented by all conforming 802.2 stations) is used exclusively. All frames must be transmitted in standard 802.2 LLC Type 1 Unnumbered Information format, with the DSAP and the SSAP fields of the 802.2 header set to the assigned global SAP value for SNAP [11]. The 24-bit Organization Code in the SNAP must be zero, and the remaining 16 bits are the EtherType from Assigned Numbers [12] (IP = 2048, ARP = 2054). Katz
