Bulletins from the Pacific Packet Radio Society - page 061

No attempt will be made by this document to standardize on the mechanism of interfacing the user data equipment to the system nodes. \It is assumed that the terminal node controllers being used will be interfaced either with an RS-232-C serial port, or some custom parallel interface.}

LEVEL 2 INTERFACE: PACKET TRANSMISSION SPECIFICATIONS

2.1 Packet Framing Specifications

No attempt will be made by this document to standardize on the mechanisms required for station nodes in attached local area networks to access the Amicon access nodes; rather, only the Amicon node (gateway) protocol will be specified, as described below.

High-level Data Link Control protocol (HDLC) will be used to control the multiple access channel.

2.2 Transmission Code

No attempt will be made by this document to specify the type of transmission code to be used within the packet. \The lack of standard specifically allows both ASCII transmission and binary file transfers; the latter will be very useful during experimental phases, for transferring program files containing the latest Amicon network updates.)

2.3 Channel Multiple Access Protocol

Access to the channel shall be by non-carrier-sensed multiple access (ALOHA) and carrier-sensed multiple access.\The latter standard allows use of sensing satellite transponder output during transmission of blocks of (identified) multiple packets, which will have transmission times greatly in excess of roundtrip travel times.}

2.4 Addressing Scheme

Each Amicon node will be assigned a single-byte unique binary identifier. Addresses will be obtained from the Amicon Coordinator at some time before a gateway comes on-line.\There are several current and planned addressing schemes for local area networks. However, the very small number and immobility of the interim network nodes allows this extremely simple and efficient mode of addressing.}

LEVEL 3 INTERFACE: NETWORK SPECIFICATIONS

3.1 - 3.4 (not applicable)

No attempt shall be made by this document to standardize the mechanisms for controlling the higher network functions of the Amicon network.\There are several schemes to attempt during the

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