>> MIB - Management Information Base

>> Table: ifTable - (.1.3.6.1.2.1.2.2.1)

Description: An interface entry containing objects at the subnetwork layer and below for a particular interface.

ifTable
OIDNameTypeAccess
.1IndexINTEGERR
.2DescrDisplayStringRW
.3TypeENUMR
.4MtuINTEGERR
.5SpeedGaugeR
.6PhysAddressPhysAddressR
.7AdminStatusENUMRW
.8OperStatusENUMR
.9LastChangeTimeTicksR
.10InOctetsCounterR
.11InUcastPktsCounterR
.12InNUcastPktsCounterR
.13InDiscardsCounterR
.14InErrorsCounterR
.15InUnknownProtosCounterR
.16OutOctetsCounterR
.17OutUcastPktsCounterR
.18OutNUcastPktsCounterR
.19OutDiscardsCounterR
.20OutErrorsCounterR
.21OutQLenGaugeR
.22SpecificOBJECT IDENTIFIERR

Index
A unique value for each interface. Its value ranges  

between 1000 and the value of ifNumber. The following 

information is encoded in the ifIndex:

a. An ifIndex between 1000 and 9999 define  

hardware  interfaces with the following attributes.

b. An ifIndex greater than or equal to 10000 defines

a software interface. Examples include the 

dialup-interfaces as defined in the  biboPPPTable.
Descr
A textual string containing information about the  

interface. The ifDesc value can be defined to help improve

readability of the interface names on the  system. By  

default, the hardware and software  interfaces are set by the

system as follows:

a. Hardware  interfaces (1000 # ifIndex # 9999):

The name is set which contains information on this

slot number, and if applicable, the unit number. For  

example: 'en1' for ethernet in slot 1, 'bri2-1' for a basic

rate interface in slot 2 unit 1.

b. Software  interfaces (ifIndex  10000):

The name is set to dialup(x) where x is the next available 

interface number on the  system.
Type
The type of interface, distinguished according to

the physical/link protocol(s) immediately `below'

the network layer in the protocol stack.

other(1)		= none of the following;

regular1822(2);

hdh1822(3);

ddn-x25(4);

rfc877-x25(5);

ethernet-csmacd(6);

iso88023-csmacd(7);

iso88024-tokenBus(8);

iso88025-tokenRing(9);

iso88026-man(10);

starLan(11);

proteon-10Mbit(12);

proteon-80Mbit(13);

hyperchannel(14);

fddi(15);

lapb(16);

sdlc(17);

ds1(18)		= T-1;

e1(19)		= european equiv. of T-1;

basicISDN(20);

primaryISDN(21)	= proprietary serial;

propPointToPointSerial(22);

ppp(23);

softwareLoopback(24);

eon(25)		= CLNP over IP [11];

ethernet-3Mbit(26);

nsip(27)             	= XNS over IP;

slip(28)		= generic SLIP;

ultra(29)		= ULTRA technologies;

ds3(30)		= T-3;

sip(31)		= SMDS;

frame-relay(32)
Enumerations:
  • other (1)
  • regular1822 (2)
  • hdh1822 (3)
  • ddn-x25 (4)
  • rfc877-x25 (5)
  • ethernet-csmacd (6)
  • iso88023-csmacd (7)
  • iso88024-tokenBus (8)
  • iso88025-tokenRing (9)
  • iso88026-man (10)
  • starLan (11)
  • proteon-10Mbit (12)
  • proteon-80Mbit (13)
  • hyperchannel (14)
  • fddi (15)
  • lapb (16)
  • sdlc (17)
  • ds1 (18)
  • e1 (19)
  • basicISDN (20)
  • primaryISDN (21)
  • propPointToPointSerial (22)
  • ppp (23)
  • softwareLoopback (24)
  • eon (25)
  • ethernet-3Mbit (26)
  • nsip (27)
  • slip (28)
  • ultra (29)
  • ds3 (30)
  • sip (31)
  • frame-relay (32)
  • adsl (94)
  • radsl (95)
  • sdsl (96)
  • vdsl (97)
  • interleave (124)
  • fast (125)
  • tunnel (131)
  • hdsl2 (168)
  • shdsl (169)
Mtu
The size of the largest datagram which can be

sent/received on the interface, specified in

octets.  For interfaces that are used for

transmitting network datagrams, this is the size

of the largest network datagram that can be sent

on the interface.
Speed
An estimate of the interface's current bandwidth

in bits per second.  For interfaces which do not

vary in bandwidth or for those where no accurate

estimation can be made, this object should contain

the nominal bandwidth.
PhysAddress
The interface's address at the protocol layer

immediately `below' the network layer in the

protocol stack.  For interfaces which do not have

such an address (e.g., a serial line), this object

should contain an octet string of zero length.
AdminStatus
The desired state of the interface.  The

testing(3) state indicates that no operational

packets can be passed.  The dialup(4) state

can be used to initiate a call.

up(1)		= ready to pass packets; 

down(2);

testing(3)	= in some test mode;

dialup(4)   	= initiate a call on a dialup

interface for some reason
Enumerations:
  • up (1)
  • down (2)
  • testing (3)
  • dialup (4)
OperStatus
The current operational state of the interface. The  

testing(3) state indicates that no operational packets can be

passed. If ifAdminStatus is down(2) then ifOperStatus

should be down(2). If ifAdminStatus is changed to up(1)

then ifOperStatus changes to up(1) if the interface is ready

to transmit and receive network traffic; it changes to  

dormant(5) for interfaces that require additional actions

(such as a dialup interface waiting for an incoming|outgoing

call); it remains in the down(2) state if and only if

there is a fault that prevents it from going to the up(1)

state. If ifOperStatus is blocked(6) no packets can be

passed and no dialup will occur for a certain time.

up(1)		= ready to pass packets;

down(2);

testing(3)	= in some test mode;

unknown(4)	= status can not be determined

for some reason.

dormant(5)	= operational but not up (eg. dialup);

blocked(6)	= currently not operational
Enumerations:
  • up (1)
  • down (2)
  • testing (3)
  • unknown (4)
  • dormant (5)
  • blocked (6)
LastChange
The value of sysUpTime at the time the interface

entered its current operational state.  If the

current state was entered prior to the last 

re-initialization of the local network management

subsystem, then this object contains a zero

value.
InOctets
The total number of octets received on the

interface, including framing characters.
InUcastPkts
The number of subnetwork-unicast packets

delivered to a higher-layer protocol.
InNUcastPkts
The number of non-unicast (i.e., 

subnetwork-broadcast or subnetwork-multicast) packets

delivered to a higher-layer protocol.
InDiscards
The number of inbound packets which were chosen

to be discarded even though no errors had been

detected to prevent their being deliverable to a

higher-layer protocol.  One possible reason for

discarding such a packet could be to free up

buffer space.
InErrors
The number of inbound packets that contained

errors preventing them from being deliverable to a

higher-layer protocol.
InUnknownProtos
The number of packets received via the interface

which were discarded because of an unknown or

unsupported protocol.
OutOctets
The total number of octets transmitted out of the

interface, including framing characters.
OutUcastPkts
The total number of packets that higher-level

protocols requested be transmitted to a

subnetwork-unicast address, including those that

were discarded or not sent.
OutNUcastPkts
The total number of packets that higher-level

protocols requested be transmitted to a 

non-unicast (i.e., a subnetwork-broadcast or

subnetwork-multicast) address, including those

that were discarded or not sent.
OutDiscards
The number of outbound packets which were chosen

to be discarded even though no errors had been

detected to prevent their being transmitted.  One

possible reason for discarding such a packet could

be to free up buffer space.
OutErrors
The number of outbound packets that could not be

transmitted because of errors.
OutQLen
The length of the output packet queue (in

packets).
Specific
A reference to MIB definitions specific to the

particular media being used to realize the

interface.  For example, if the interface is

realized by an ethernet, then the value of this

object refers to a document defining objects

specific to ethernet.  If this information is not

present, its value should be set to the OBJECT

IDENTIFIER { 0 0 }, which is a syntatically valid

object identifier, and any conformant

implementation of ASN.1 and BER must be able to

generate and recognize this value.


Copyright ©2003 by BinTec Access Networks GmbH