HK> A comma separated list is not very flexible, but instead inherently
 HK> quite rigid. A flexible format have to be built on field
 HK> identifiers, that is the only way to guarantee future extentions
 HK> without breaking existent next generation software. 

I believe that a comma separated list can be reasonably flexible provided
that all software that process it is written with extensibility in mind. 


Among other things this means that processing software should from the very
start be written to tolerate unknown fields.

Field identifiers (or rather field group identifiers) could be used to
identify each group of connectivity related fields:

,505,GET,Lulea,Goran_Eriksson,\
*POTS*,46-920-257910,33600,XX,V34,\
*ISDN*,46-920-257910,64000,CM,XX,X75,\
*IBN*,getibn.nospam.se,CM,\
*ITN*,getitn.nospam.com:9999,CM,\
*ISE*,irex{at}get.nospam.com

where the \ only implies line-breaks which have been inserted here for clarity.

With this

1. I can specify different on-line hours for different connectivity types
all in one nodelist entry.
2. I can specify different host names and different ports for IP protocols
all in one nodelist entry.
3. I can specify different file request capabilities for different
connectivity types all in one nodelist entry.

and a number of other things I haven't demonstrated above.

New connectivity field groups may be added (e.g. *AX25* for packet radio
links) without any problems provided that older software understands to
gently ignore the AX.25 connectivity group. The internal syntax of a
connectivity field group can be freely defined as long as no ambiguities
arise.


One advantage with a text file format is that it's easy to maintain the
information in the nodelist with your favourite text editor.

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