PMDF System Manager's Guide
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41.3.1 Network Transport Addresses

PMDF-X400 requires the use of an OSI address for the X.400 Reliable Transfer Service. The format of these OSI addresses is specified in RFC 1278. OSI addresses consist of four parts:

The combination of an NSAP and TSEL is called a "Transport Service Access Point", TSAP, or Transport Address. An NSAP, TSEL, and SSEL is called a "Session Service Access Point", SSAP, or Session Address. Finally, an NSAP, TSEL, SSEL, and PSEL is called a "Presentation Service Access Point", PSAP, or Presentation Address.

PMDF-X400 uses the Transport Address, or TSAP, for 1984 or 1988-X410 modes, and the Presentation Address, or PSAP, for 1988-NORMAL mode. The written format of a TSAP for PMDF-X400 requires the TSEL component, followed by a forward slash, /, followed by the NSAP component: 


tsel / nsap-address
while the written format of a PSAP requires a PSEL, SSEL, TSEL, and NSAP, each separated by a forward slash: 


psel / ssel / tsel / nsap-address

Table 41-6 shows sample TSAP and PSAP addresses.

41.3.1.1 Selectors (PSEL, SSEL, and TSEL)

A selector can be specified as a numeric integer, a hexadecimal string of octets, a printable string, or an empty string, as presented in Table 41-5.

Table 41-5 Transport Selector Format
#decimal-digit-string Decimal integer between 0 and 65535
'hexadecimal-digit-string 'H Requires 2 digits per octet, max length 63
"printable-string " One printable character per octet, max length 63
"" The empty string, selector present but empty

A printable-string can contain the characters a-z, A-Z, , 0-9, -, ., and +.

41.3.1.2 Network Service Access Point (NSAP)

PMDF-X400 allows three forms of NSAP address: Internet, X.25, and "real NSAP". The Internet form allows for the specification of IP host names or addresses and an optional TCP port number by using the "Internet=" form identifier. You should use the Internet form if you are using X.400 over TCP/IP. The X.25 form allows for the specification of an X.25 DTE address by using the "Int-X25=" form identifier. You should use the X.25 form if you are using X.400 over OSI Transport over CONS with an X.25 network and are running on OpenVMS or Tru64 UNIX; the X.25 form should not be used on Solaris. The "real NSAP" form allows for the specification of an OSI NSAP address by using the "NSAP=" form identifier. You should use the real NSAP form if you are connected to an OSI network and can specify NSAP addresses on that network; in particular, the real NSAP form is always used when using OSI transport on Solaris. 


Internet=IP-domain-name-or-address+TCP-port-number
Int-X25=DTE-address
NSAP=nsap-address

On Solaris, note that SunLink OSI requires a CONS NSAP address which maps onto an X.121 address for use over X.25. Therefore on Solaris you must use the real NSAP address form with PMDF-X400, rather than the Int-X25 form. See the SunLink OSI Administrator's Guide for details on constructing the appropriate NSAP address for use over X.25.

For the Internet form of IP addresses, the + followed by TCP-port-number is optional. If not present, TCP port number 102 will be used. Note that IP-domain-name-or-address can contain a host name, a complete domain name, or a dotted- decimal IP address. The name or address must be available for use as part of your TCP/IP transport's configuration. PMDF-X400 does nothing itself to define the address nor ensure that the address is reachable.

For the Int-X25 (OpenVMS or Tru64 UNIX only) or NSAP forms of addresses, the DTE-address or nsap-address must be available for use as part of your OSI transport configuration. PMDF-X400 does not configure your OSI transport, nor ensure that the address is reachable.

See Table 41-6 for some example addresses.

Table 41-6 Example TSAP and PSAP Addresses
Example TSAP address for 1984 mode or 1988-X410 mode Description
"PMDF-X400"/Internet=X400.EXAMPLE.COM TCP/IP Internet with standard port
'013a5e03'H/Internet=X400.EXAMPLE.COM TCP/IP with octet-string TSEL
"X400-MRX"/Int-X25=12345678910 OSI using X.25 DTE address+
""/NSAP=49004008002B1D615121 OSI NSAP address with empty TSEL
Example PSAP address for 1988-Normal mode Description
"MTA"/"MTA"/"PMDF-X400"/Internet=X400.EXAMPLE.COM TCP/IP Internet
"PP"/"MTA"/"PMDF-X400"/Int-X25=12345678910 OSI using X.25 DTE address+
"MTA"/"MTA"/"PMDF-X400"/NSAP=49004008002B1D615121 OSI NSAP

+OpenVMS and Tru64 UNIX only

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