Getting Technical

For technical information about FidoNet please see www.ftsc.org

Expanding a Theme on ERN

4 May 2001

A short while ago I wrote on ERN routing and some of the basic ideas used as well as the history. This next piece will take it a bit farther to show both flags in testing that may be useful for this purpose, and some more concepts on how charts are developed.

A chart, is a text file used to show how sites interconnect so that netmail can be sent from one route to another. People who route netmail, use these charts in their various different forms, to enter manually, 'routing statements' to handle netmail sent to them, and destined for another net.

How are these charts made? Well, it depends on the region and the zone involved. They are not all the same, nor are they all published in the same format, even within the same zone. But they all have one thing in common, for all that the formats differ. A sysop (normally the REC but not always) checks what route each known net in their region desires, and types this up into a text file and sends it out to those who need it.

In Zone1, these are hatched in a filebone area. In Z6, they are posted in a communal sysop echo.

However they are sent out, eventually someone has to add them together. The methods for that may be just 'pasting them on' (as in zone6 apparently) or with a major zone level chart as Z1 uses.

Each method is prone to human error as it requires a human to do some tasks and make sure all works in tandem and that there are no apparent conflicts or typographical errors.

Only a person with true divine inspiration and advance knowledge can be perfect at this, but as a hobby, it's working pretty well most of the time.

Some however like to look to automated tools to produce such lists. To do this, the control has (under testing) been placed back with the NC level to directly reflect feeds. This is a Z1 test at this time and exists only in 3 regions, with only 1 (R12) having a full test implementation.

This test series involves several nodelist flags. No one can yet actually change mailer routing automatically based on them. They currently exist only to make potential routelists based on software still in testing.

A new flag was added to the test zone in Z1. Please note, all test flags until accepted belong in the USER comment area. That means you use ,U,flag

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Janis has approved a new user flag for testing in Z1.

U,DRVIA

This flag optionally may carry a :Z:net/node uplink primary. Specifically there is to be only one entry of this flag per region and it is used to designate the default region routing site for all nets in that region if no other route is known. It is applied to the primary use number of that node only.

EX: 1:140/1 is the primary 'use' number for Bob Seaborn so if he were the default region route for his net, it would go on that number and that one only

EX2: Joe Davis is the default region route for R13 nets. Joe has numbers 1:13/1 and 1:261/1380. 1:261/1380 is his primary use number so the ,U,DRVIA goes on that number.

This may complete the set of needed *RVIA user flags. For a reminder, here ar the other 2 listed in earlier articles.

,U,MRVIA:(uplink address). There are to be 1 per net (no more? Undecided by use yet) but the site specifically must be able to reach all nodes in their ne via routing services. Just like DRVIA, it is applied only to the node's primary tossing 'use' address.

,U,RVIA:(uplink address). There may be as many as needed in each net but specifically this is used just to show exceptions to default net links. If node has a direct connection to the same path as the net does but with no interconnection to the net, it is valid to list it.

EX: Larry DiFava in 1:270 draws from 1:275/103 and carries a ,U,RVIA:1:275/103 listing. This is correct.

,U,RVIA listings are not valid methods of reaching other than the node in that list. They are either questionable or non-functional to reach others in that net.

xxcarol