| Description | This parameter specifies the direction of enabled
communication, either inbound(1), outbound(2), or
biDirectional(3).
The semantics of this object depends on the protocol
the rule relates to. If the rule is independent of
the transport protocol (midcomRuleTransportProtocol
has a value of 0) or if the transport protocol is UDP,
then the value of midcomRuleFlowDirection indicates
the direction of packets traversing the middlebox.
In this case, value inbound(1) indicates that packets
are traversing from outside to inside, value outbound(2)
indicates that packets are traversing from inside to
outside. For both values, inbound(1) and outbound(2)
packets can traverse the middlebox only unidirectional.
A bidirectional flow is indicated by value
biDirectional(3).
If the transport protocol is TCP, the packet flow is
always bidirectional, but the value of
midcomRuleFlowDirection indicates that:
- inbound(1): bidirectional TCP packet flow.
First packet, with TCP SYN flag set, must arrive
at an outside interface of the middlebox.
- outbound(2): bidirectional TCP packet flow.
First packet, with TCP SYN flag set, must arrive
at an inside interface of the middlebox.
- biDirectional(3): bidirectional TCP packet flow.
First packet, with TCP SYN flag set, may arrive
at an inside or an outside interface of the middlebox.
This object is used as input to a request for
establishing a policy enable rule as well as for
indicating the properties of an established policy rule.
If object midcomRuleOperStatus of the same entry has a
value of either newEntry(1), setting(2), or reserved(7),
then this object can be written by a manager in order to
specify a requested direction to be enabled by a policy
rule. Writing to this object in any state other than
newEntry(1), setting(2), or reserved(7) will always fail
with an 'inconsistentValue' error.
Note that this error code is SNMP specific. If the MIB
module is used with other protocols than SNMP, errors with
similar semantics specific to those protocols should be
returned.
If object midcomRuleOperStatus of the same entry has the
value enabled(8), then this object indicates the enabled
flow direction.
If object midcomRuleOperStatus of the same entry has a
value other than newEntry(1), setting(2), reserved(7), or
enabled(8), then the value of this object is irrelevant. |