This MIB provides information on the IP-RAN traffic
from cell site to aggregation site in the following
situations.  In an GSM environment the cell site will
be the Base station Transceiver System(BTS) and the
aggregation site will be the Base Station
Controller(BSC).  In the UMTS environment the cell
site will be the B-Node and the aggregation site will
Radio Network Controller(RNC).
        
        
        
There are two typical type backhaul, also know
as longhaul, links.  The traditional backhaul
connection consists of a PPP multilink containing two
or more E1 or T1 links or ATM or ATM/IMA.  The
alternate backhaul is traffic transported using
IP cloud.
        
        
Simple back-to-back configuration
---------------------------------
   This setup consists of two devices that
   support a limited number of GSM and UMTS links.
   They are deployed in pairs and inserted between
   the existing BTS device and BSC device.
        
       BTS site               BSC site
        
   GSM-Abis                           GSM-Abis
   ----||||||||    Backhaul   ||||||||----
   ----|      |---------------|      |----
   ----|      |---------------|      |----
       ||||||||               ||||||||
        
       RNC  B-Node site       RNC
        
   UMTS                                UMTS
   ----||||||||    Backhaul   ||||||||----
   ----|      |---------------|      |----
   ----|      |---------------|      |----
       ||||||||               ||||||||
          |                       |
          |-----------------------|
           Alternate backhaul over
           IP cloud
        
        
Aggregate node configuration
----------------------------
This configuration consists of one aggregate node
located at BSC site and several devices at BTS
sites. The aggregate device has a seperate backhaul
link to each BTS site.
        
    BTS site                BSC site
        
                           Aggregate
GSM                                GSM
----||||||||    Backhaul   ||||||||----
----|      |---------------|      |----
----|      |---------------|      |----
    ||||||||               |      |
       .                   |      | .
       .                   |      | .
GSM    .                   |      | .
----||||||||    Backhaul   |      |----
----|      |---------------|      |----
----|      |---------------|      |----
    ||||||||               ||||||||
        
        
     RNC                   B-Node
UMTS                                UMTS
----||||||||    Backhaul   ||||||||----
----|      |---------------|      |----
----|      |---------------|      |----
    ||||||||               |      |
       |     Alternate     |      |
       |        ....       |      |
       -------.      .     |      |
              . IP   .     |      |
              . Cloud.-----|      |
              .      .     |      |
       -------.      .     |      |
       |       ......      |      |
       |    Backhaul       |      |
UMTS   |                   |      |
----||||||||    Backhaul   |      |----
----|      |---------------|      |----
----|      |---------------|      |----
    ||||||||               ||||||||
        
        
                   Compression
                   Multiplexing
                       |
BSC <---------->||||||||  V   ||||||||<---------->BTS
     . GSM    . |      |<---->|      | . GSM    .
     . A(bis) . |      |<---->|      | . A(bis) .
    <---------->||||||||      ||||||||<---------->
         A                A
         |                |
    ShortHaul         BackHaul
        
    Multiple E1/T1 Back Haul Links
        
Entries in these tables cannot be created or deleted
by the network management system.  All entries are
created or deleted by the agent.
        
Shorthaul interfaces support the following protocols.
        
Protocol    ifType
--------    ----------------------------
GSM-Abis    propPointToPointSerial(22)
UMTS-iub    atm(37)
UMTS/IMA    atmSubInterface(134)
           aal5(49)
ifType.44 = atmIma(107)
        
        
The following list provides the currently allowed
backhaul interfaces types.  Additional interfaces
types will be added as they are supported.
        
ifType
---------------------------
ethernetCsmacd(6)
ppp(23) as Multilink bundle
pppMultilinkBundle(108)
        
        
In order to manage the IP-RAN optimization solution, two
key factors must be monitored. The first and most
important is the amount of traffic sent over the backhaul
interface.  The second is compression efficiency which has
a direct impact amount of traffic placed backhaul link.
        
MIB Structure
-------------
The MIB has the following structure.
        
Shorthaul information tables:
 cirbhInfoTable
        
Shorthaul Alarm Information tables
 cirbhGsmAlarmTable
 cirbhUmtsConnectionTable
 cirbhUmtsAlarmTable
        
Shorthaul statistics tables
 cirbhStatsTable
 cirbhErrorsTable(deprecated)
 cirbhShortHaulHistoryTable(obsolete)
 cirbhCongestionTable
 cirbhGsmErrorsTable(replaces cirbhErrorsTable)
 cirbhUmtsErrorsTable(replaces cirbhErrorsTable)
        
Backhaul information tables
 cirbhBackHaulTable(obsolete)
        
Backhaul statistics tables
 cirbhBackHaulHistoryTable(obsolete)
 cirbhBackHaulStatsTable(obsolete)
 cirbhBackHaulStatsHistoryTable(deprecated)
        
Abbreviations:
    A-bis   Interface between BSC and BTS
    AAL2    ATM Adaptation Layer type 2
    AAL5    ATM Adaptation Layer type 5
    AIM     Advanced Interface Module
    AgNode  Aggregation Node
    ALCAP   Access Link Control Application Part
    AMR     Adaptive Multi-Rate speech codec
    ATM     Asynchronous Transfer Mode
    BCH     Broadcast Channel
    BSC     Base Station Controller.
    BTS     Base Station Transceiver System
    CDF     CID Definition Field
    CID     Channel IDentification
    CPCH    Common Packet Channel
    DCH     Dedicated Channel
    DSCH    Downlink Shared Channel
    DTX     Discontinuous Transmission (mechanism)
    FACH    Forward Link Access Channel
    GSM     Global System for Mobile communications
    IMA     Inverse Multiplexing for ATM
    Iub     Node B to RNC interface
    OC3     Optical Carrier 3
    OSF     OffSet Field
    LAPD    Link Access Protocol on Dm Channel
    O&M     Operations and Maintenance
    MLPPP   Multi-Link PPP
    MS      Mobile Station (Handset)
    NBAP    Node B Application Part
    NNI     Network to Network Interface
    Node-B  Node B
    PCH     Paging Channel
    PVC     Permanent Virtual Circuit
    RAN     Radio Access Network
    SVC     Switched Virtual Circuit
    RACH    Random Access Channel
    RNC     Radio Network Controller
    SAR     Segment Assembly Reassembly
    SDC     Traffic Channel
    SDH     Signaling Channel
    SPVC    Soft Permanent Virtual Circuit
    SSCOP   Service Specific Connection Oriented Protocol
    STC     Signaling Transport Converter
    STM-1   Synchronous Transport Module type 1
    TRAU    Transcoder Unit
    UMTS    Universal Mobile Telecommunications System
    UNI     User to Network Interface
    USCH    Uplink Shared Channel
    UTRAN   UMTS Terrestrial Radio Access Network
    VCI     Virtual Channel Identifier
    VPI     Virtual Path Identifier