| Description | This is the frame relay(logical) port number.
For Service Modules, supporting ifTable, this
must be the ifIndex value of the frame relay port.
The port number value supported depends upon the
following for each Service Module:
- type(Channelized, Unchannelized, Fractional etc)
of physical line and number of physical lines
- Number of physical line supported
- Limitations due to Service Module Hardware components.
Port Number mapping is as follows:
(NOTE: All the Supported Service Module information is
not provided here).
T1(channelized) : 24 Time Slots * Max #Lines Supported.
Example: 8 Port Service Module - 1..192(24*8)
E1(channelized) : 31 Time Slots * Max #Lines Supported.
Example: 8 Port Service Module - 1..248(31*8)
T3 Channelized :
Example: 2CT3 Service Module: 1-256(Limited by hardware)
Unchannelized VHS : Range is 1-2
(T3/E3/HS2/T3B/E3B/HS2B-HSSI)
FRSM-HS2B-12IN1 : Range is 1-8
FRSM-12 : same as ifIndex value.
With the above convention, Port Number mapping
is as follows:
T1 Service Module : Range is 1-192.
E1 Service Module : Range is 1-248.
2CT3 Service Module : Range is 1-256
NOTE:
For other Service Modules(Where ifTable is supported):
This value for this object must be same as the
ifIndex value for the frame relay port ifTable.
The frame relay ports identified by ifType values
frameRelayService(44) and frForward(158) are
valid for this object.
Since, Frame Relay Port table is used for creating
entries in ifTable, it sounds odd to specify ifIndex
value for this object, even before creating the
ifTable entries!.
The reason(s) for this is as follows:
- There are tables in other frame relay mibs,
which are indexed by auxiliary objects(objects
which are both specified in the INDEX clause
and columnar objects of the same row) whose
value is supposed to be same as 'portNum'.
These MIBs have been used earlier by NMS Applications
for the other product lines(MGX8250, MGX8220 etc).
- The same frame relay tables in used in other
products has been decided to use in new
products(for example MGX8850 with FRSM-12 Service Module).
It is a requirement that ifTable must be supported
in New Service Modules.
If we use ifIndex value of the frame relay port
(after creation) in other tables(FR Port Stats, FR R
Resource Partition or FR Connection etc), and if ifIndex
value is different than 'portNum', then it will
break the NMS applications which have been
using this MIB with the assumptions that 'portNum'
and INDEXes(For example: frResPartPortNum,
lmiCnfPortNum, etc) are same.
To avoid this confusion, it is required that
'portNum' value must be same as 'ifIndex' of
the frame relay port. |