1. Network Management Specification
8000-A2-GB30-30
June 2004
21
The following table shows the values supported :
Therefore this object will be set to the value of 127.
4. Evolution of the Interfaces Group of MIB-II (RFC 2863)
The interfaces group consists of an object indicating the number of interfaces supported by
the unit and an interface table containing an entry for each interface in the BAC. Since RFC
2863 is an SNMPv2 MIB it will be converted to SNMPv1 for support by the BAC. There
will be entries for WAN interfaces, ATM cell interfaces, an AAL5 interface, management
interfaces and DSL interfaces.
4.1
“ifNumber” Object (interfaces 1)
ifNumber will be supported as specified in the Evolution MIB and will specify the number
of rows in the ifTable for this particular device.
4.1.1
“ifIndex” Object (ifEntry 1)
This object provides the index into the ifTable and typically into tables in other MIBs also.
A unique value, greater than zero, for each interface or interface sublayer in the managed
system. It is recommended that values be assigned contiguously starting from 1. The value
for each interface sublayer must remain constant at least from one re-initialization of the
entity’s network management system to the next re-initialization.
4.1.1.1
ifIndex scheme
This section introduces the ifIndex scheme to be used in the BAC product. It describes the
interfaces to be managed as specified in the system requirements along with their
corresponding ifIndex assigned. The assignment of the values to the ifIndex in the product
is static and maintained across power cycles and software upgrades. The first column in
Table 1-6, BAC Interface List
, is the Interface description. The second column
corresponds to the layer in the stack where this interface fits (It does not necessary match
the layer in the OSI model). The third column is the number of this interface supported in
the current software release. The forth column is the maximum number of this interface
that is envisioned in this product. The fifth column is the name associated with that
instance of the interface.
The ‘x’ suffix in some ifName values corresponds to the interface/port number within the
same chassis.
Table 1-5.
sysServices
Layer (L)
Functionality
Value(2^(L-1)
Sum
1
Physical
2^(1-1) = 2^0 = 1
1
2
DataLink/Subnetwork
2^(2-1) = 2^1 = 2
3
3
Internet
2^(3-1) = 2^2 = 4
7
4
End-to-End
2^(4-1) = 2^3 = 8
15
5
Session
2^(5-1) = 2^4 = 16
31
6
Presentation
2^(6-1) = 2^5 = 32
63
7
Application
2^(7-1) = 2^6 = 64
127
