[pim] Orie Steele's No Objection on draft-ietf-pim-3810bis-11: (with COMMENT)

[Orie Steele via Datatracker <[e-mail]>]

Orie Steele has entered the following ballot position for
draft-ietf-pim-3810bis-11: No Objection

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COMMENT:
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# Orie Steele, ART AD, comments for draft-ietf-pim-3810bis-11
CC @OR13

https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-pim-3810bis-11.txt&submitcheck=True

## Comments

### Why not MUST NOT?

```
1182               multicast address, if it is non-empty.  An SSM-aware host
1183               SHOULD NOT send a MODE_IS_EXCLUDE record type for multicast
1184               addresses that fall within the SSM address range as they will
1185               be ignored by SSM-aware routers [RFC4604].
```

```
1206               the specified multicast address, if it is non-empty.  An SSM-
1207               aware host SHOULD NOT send a CHANGE_TO_EXCLUDE_MODE record
1208               type for multicast addresses that fall within the SSM address
1209               range.
```

Is this simply a SHOULD because it won't cause harm, because it is ignored?

Are there cases where an SSM-aware host MUST / MUST NOT send MODE_IS_EXCLUDE or
CHANGE_TO_EXCLUDE_MODE ?

### Why not MUST?

```
1292       Records of the Report message.  From now on, it will treat packets
1293       sent to those multicast addresses according to this new listening
1294       state.  Once a valid link-local address is available, a node SHOULD
1295       generate new MLDv2 Report messages for all multicast addresses joined
1296       on the interface.
```

Under which conditions should a node not generate new new MLDv2 Report messages.

```
2414       SHOULD log an error.  It is RECOMMENDED that implementions provide a
2415       configuration option to disable use of Host Compatibility Mode to
2416       allow networks to operate only in SSM mode.  This configuration
2417       option SHOULD be disabled by default.
```

implementions -> implementations

Under which conditions is it ok to leave this configuration enabled by default?