OSI/AS Configuration and Management Manual

NSAP Addressing
OSI/AS Configuration and Management Manual—424119-001
3-9
AFI Component
The parts of an NSAP address are as follows:
•
IDP
•
DSP
These fields are discussed in more detail in the following subsections:
•
AFI Component on this page
•
IDI Component on page 3-10
•
DSP Component on page 3-11
AFI Component
The AFI (authority and format identifier) contains information on the network
addressing authority that regulates the domain specified in the IDP, as well as
information on the format of the IDI and the DSP. The network addressing authority
specifies the meaning of each AFI value; network addressing domains use the AFI
values.
The AFI contains a two-digit number (ranging from 00 through 99) that specifies the
following information:
•
Network addressing authority responsible for regulating IDI values
•
Syntax type of the DSP
•
Significance (or lack thereof) of leading zero digits in the IDI
Initial domain
part (IDP)
Unambiguously identifies a subdomain at the highest level. This
field is always expressed as a range of 2 through 17 decimal
digits.
AFI: The authority and format identifier (AFI) contains
information on the network addressing authority that regulates
the domain specified in the IDP along with information on the
format of the IDI and the DSP.
IDI: The initial domain identifier (IDI) contains information on
the domain governed by the network addressing authority
specified in the AFI.
Domain specific
part (DSP)
Is the last component of the NSAP address. The contents are
determined by the information contained in the AFI and IDI and
are regulated by the network addressing authority associated with
the subdomain identified in the IDP.