RE: [RPRWG] Question about Row 22 and Row 23 of Table 10.13

["Jason Fan" <Jason@xxxxxxxxxxxx>]

Hi,

 

The reason that rows 22 and 23 of Table 10.13 (now rows 21 and 22 in Table 10.12 in D2.6) are correct is:

 

A station receives a TP frame from a station i hops away on ringlet0, so ri=0 and otherRi=1. There are two possibilities.

 

1. The TP frame indicates an edge on the east side (ringlet1 receive side) of the source station. If the source station is not the neighbor station (one hop away), then all stations i hops or further away on ringlet0 have their topoEntry[ri][j].valid and topoEntry[ri][j].reachable fields set to FALSE. The reason that the field being set is topoEntry[ri][j] is because the valid field corresponds to validity of the station from whith TP frames are recevied on ringlet ri. The reachable field in topoEntry[ri][j] corresponds to the reachability of the station on ringlet otherRi (see definitions in 10.3). There is no need to set any fields in topoEntry[otherRi][j] based on the receipt of this TP frame because other TP frames will be received from a different station reporting an edge on ringlet1.

 

If the source station is one hop away, then the setting of the valid and reachable fields is handled in stage 2 of the topology database update.

 

2. The TP frame indicates an edge on the west side (ringlet0 receive side) of the source station. The only difference with case 1 is that the exception case of a source station one hop away does not have to be handled differently in this case.

 

Jason Fan

Luminous Networks

-----Original Message-----
From: zhang xiaolin [mailto:bit_walker@xxxxxxxxxx]
Sent: Thursday, October 16, 2003 1:07 AM
To: stds-802-17@xxxxxxxx
Subject: [RPRWG] Question about Row 22 and Row 23 of Table 10.13

Hi, everyone,

In the Draft 2.5, I think there is a error in Row 22 and Row 23 of table 10.13.

If the station receive a TP frame from ringlet1 that indicates a edge in the west side of the source station, all the stations beyond the source station, including the source station, should be unreachable in ringlet0, not in ringlet1. If the TP frame indicates a edge in the east side of the source station, all the stations beyond the source station, not including the source station, should be unreachable in ringlet0.

So, I think the correct action of Row 22 should be:

for (j=i;j<=MAX_STATIONS;j+= 1) {
topoDB.entry[otherRi][j].valid=FALSE;
topoDB.entry[otherRi][j].reachability=FALSE;
}

and the action of Row 23 should be:

for (j=i+1;j<=MAX_STATIONS;j+= 1) {
topoDB.entry[otherRi][j].valid=FALSE;
topoDB.entry[otherRi][j].reachability=FALSE;
}.

How do you think about it?

 

 

Best Regards,

 

Walker