RFC 1101:DNS Encoding of Network Names and Other T...
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TCP


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... method which would be sufficiently general to set a good precedent for future mappings, for example, between TCP-port names and numbers, autonomous system ...
... existing support for host names, and another family of structures for future yellow pages (YP) functions such as conversions between TCP- port numbers and mnemonics ...


... Although a single, centrally-managed YP for well-known values such as TCP-port is desirable, we regard organization-specific YPs for, say, locally defined TCP ...
... TCP-port is desirable, we regard organization-specific YPs for, say, locally defined TCP ports as a natural extension, as are combinations of YPs using search ...
... <YP-origin> :=YP <from-data-type>:=TCP-port | IN-ADDR | Number | ...
... TCP-port Six character alphanumeric ...


... TCP-PORT ...
... $origin Number.TCP-port.YP. ...
... 23 PTR TELNET.TCP-port.Number.YP. 25 PTR SMTP ...
... port.Number.YP. 25 PTR SMTP.TCP-port.Number.YP. ...
... port.Number.YP. $origin TCP-port.Number.YP. ...
... TELNET PTR 23.Number.TCP-port.YP. ...
... SMTP PTR 25.Number.TCP-port.YP. ...
... search list. Thus, if the organization ISI.EDU wished to define locally meaningful TCP-PORT, it would define the domains: ...
... <TCP-port.Number.YP.ISI.EDU> and <Number.TCP-port ...
... <TCP-port.Number.YP.ISI.EDU> and <Number.TCP-port.YP.ISI.EDU>. ...



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