RS-449
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| The five layer TCP/IP model |
| 5. Application layer |
|
DHCP • DNS • FTP • HTTP • IMAP4 • IRC • NNTP • XMPP • MIME • POP3 • SIP • SMTP • SNMP • SSH • TELNET • BGP • RPC • RTP • RTCP • TLS/SSL • SDP • SOAP • L2TP • PPTP • … |
| 4. Transport layer |
| 3. Network layer |
| 2. Data link layer |
|
ATM • DTM • Ethernet • FDDI • Frame Relay • GPRS • PPP • ARP • RARP • … |
| 1. Physical layer |
|
Ethernet physical layer • ISDN • Modems • PLC • SONET/SDH • G.709 • Wi-Fi • … |
The RS-449 specifiecs the functional and mechanical characteristics of the interface between data terminal equipment and data communications equipment. The electrical signalling standards intended for use with RS 449 are RS-422 for balanced signals, and RS-423 for the unbalanced signals, with data rates to 2,000,000 bits per second. The standard specified two D-subminiature connectors with 37 and 9 pins for the primary and secondary data circuits. Though never applied on personal computers, this interface is found on some network communication equipment. The full title of the standard is EIA-449 General Purpose 37-Position and 9-Position Interface for Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange. It was withdrawn in September, 1992.
[edit] External links
[edit] Reference
- Electronics Industries Association, EIA Standard 449 November 1977, reprinted in Telebyte Technology "Data Communication Library" Greenlawn NY, 1985, no ISBN, no Library of Congress card number
