The MIB is used to manage and optimize power usage
in networks. 

Cisco EnergyWise is a specification of data, discovery and
protocols for managing power on and between network devices.

An entity is Cisco EnergyWise compatible, if it complies with
Cisco EnergyWise specification.

A Cisco EnergyWise entity is characterized by the power related
attributes of a physical entity present in ENTITY-MIB. 

Cisco EnergyWise solves the problem of Network Power
Management.   One of goals of Cisco EnergyWise is to manage
power on network level.  Some solutions in FCAPS have focused
on
managing a single element but Cisco EnergyWise provides the
capability to handle the management of a network of devices, as
well as a single device. 

Concepts and Definitions:
=========================
Cisco EnergyWise Entity: A physical entity that is part of the
network that provides power or draws power from another 
part of the network.

Cisco EnergyWise Level: A uniform way to classify power
settings on an EnergyWise entity.  Levels are guidelines for
the manufacturers of entity (e.g., shut, hibernate, sleep,
standby).

Cisco EnergyWise Usage: The consumption of power by a Cisco
EnergyWise entity in watts.

    Current         The current power consumption by an 
                    Cisco EnergyWise entity.

    Provisioned     The maximum power a Cisco EnergyWise
                    entity can draw in the current level.

    Usage Vector    A vector 0..10 representing the maximum
                    power a Cisco EnergyWise entity can draw at
                    each level. 

    Delta Vector    This defines a vector 0..10 representing
                    the difference between the Current and
                    Usage Vector for each level.

Cisco EnergyWise Entity Power Unit: This is used to represent
smaller or larger quantities of Cisco EnergyWise usage and
conforms to the standard prefixes for the SI (System
International) units of measure.  The value represents an
exponent of 10.

    For example, if current usage of an EnergyWise entity is 
    3, it could be 3 W, 3 mW, 3 KW, 3 MW depending on the value
    of Cisco EnergyWise power unit, i.e. 0, -3, 3, or 6 
    respectively.

Cisco EnergyWise Domain: A collection of entities that is
divided into manageable sets.  Switch, IP phones, IP cameras,
lighting controllers can be Cisco EnergyWise entities, all part
of a domain.  A domain can contain multiple devices.

Cisco EnergyWise Entity Importance: The importance attribute of
an entity enables the management station to differentiate other
Cisco EnergyWise entities in the domain with a different
business context.  This also provides a choice to the
administrators to manage power in context of importance.

    For example, assuming we have 2 phones deployed in a
    enterprise.  One phone is in a shared spare office and one 
    used by trader generating lot of money as part of core
    business of enterprise.

    This clearly demonstrates that the phone used by trader is
    more important than the phone used in the spare office.

Nanny Vector: A vector of bits, representing different features
(E.g., sleep, wakeup, shutdown) supported on a Cisco
EnergyWise entity.  Setting of some of the features on the
Cisco EnergyWise entity can be managed by itself, but for some
others, a parent has to nanny.

Nanny: An EnergyWise entity acts on behalf of another 
another Cisco EnergyWise entity.

Cisco EnergyWise Parent: A Cisco EnergyWise entity that does
not have a nanny vector.  This entity can manage all its power
setting for itself as well as for Cisco EnergyWise entities
contained in it.  The contained in relationship is same as
defined in ENTITY-MIB. 

Cisco EnergyWise Child: A Cisco EnergyWise entity that has a
nanny vector.  It requires a Cisco EnergyWise parent to serve
as nanny.  Depending on the nanny vector a Cisco EnergyWise
child can be fully or partially managed.  

Cisco EnergyWise Neighbor: A Cisco EnergyWise entity to which
Cisco EnergyWise protocol events can be forwarded to.  An
entity can either discover a neighbor using a discovery
protocol, or the neighbor can be configured as a static
neighbor
by the Management station.  A Cisco EnergyWise parent may also
nanny a Cisco EnergyWise neighbor.

    For example, A Cisco EnergyWise compatible entity like an
    IP phone, connected to a port on the switch, can provide a 
    nanny vector to the switch to serve as a nanny.

Cisco EnergyWise Proxy: A device attached to a port that does
not understand the Cisco EnergyWise protocol, but has the
provision to manage power through network APIs or a proprietary
protocol.  

A Proxy is always configured on a port.  It allows the
Cisco EnergyWise protocol to be used with other non networking
devices that draw power indirectly. 

    For example, a Lutron controller (building lighting 
    controller) is a nonnetworking device which does not
    understand Cisco EnergyWise protocol.  However, it runs a 
    proprietary BACNET protocol.

The following diagram represents the relationship between 
cewEntTable and cewNeighborTable, 
cewEntTable and cewProxyTable.


                      Points to a 
--------------------- nbr entry for    ---------------------
| EntPhyIdx | NbrId | which it does    | NbrId |  Name     |
--------------------- Nanny            ---------------------
| 101       |   1   |----------------->|    1  | IP-Phone1 |
---------------------                  ---------------------
| 102       |   0   |                  |    2  | Switch1   |
---------------------                  ---------------------
| 103       |   3   |----------------->|    3  | IP-Phone2 |
---------------------                  ---------------------
| 104       |   0   |----------        |       |           |
---------------------         |        ---------------------
| 105       |   0   |-----    |        |       |           |
---------------------    |    |        ---------------------
                         |    |
Points to proxy          |    |   -----------------------------
entry configured         |    |   | EntPhyIdx | PrxyId | Name |
on this port.            |    |  -----------------------------
                         |    |-->|  104      |  1     | LC1  |
                         |        -----------------------------
                         |        |           |        |      |
                         |        -----------------------------
                         -------> |  105      |  3     | BL2  |
                                  -----------------------------
                                  |           |        |      |
                                  -----------------------------

Cisco EnergyWise Event: It is a policy that can be either
configured on a Cisco EnergyWise entity or received from
other Cisco EnergyWise entities.  Using this, a Cisco
EnergyWise entity can adjust its power settings according
to some criteria, typically time.

    For example, a Management station can configure an
    EnergyWise event on a switch to control devices in branch 
    offices, to go to power level standby at 8pm and power
    level full at 7am.

Cisco Energywise Query: It is a Cisco Energywise CLI used to
get
power information from the entire Energywise Domain. Queries
are
delivered, hop by hop, through the Domain using the established
neighbor information. Authentication is by the domain's shared
secret, and only authenticated queries can be sent to
EndPoints. EnergyWise supports various kinds of queries,
including set, collect, sum and delta.
   set: changes or turns off power usage levels
   collect: retrieves power usage information (in watts) from
the cloud.  
   sum: aggregates power information across multiple Members
and Endpoints. 
   delta: runs what if calculations.

Cisco EnergyWise Neighbor Id : The Cisco EnergyWise Neighbor's
unique Id is made up of two parts:-
    UDI: Unique Device Indentification of the Cisco EnergyWise
Neighbor.
    EntPhysicalIndex: The Entity Physical Index of the Cisco
EnergyWise Neighbor.
A combination of these two values provide a unique Id for the
Cisco EnergyWise Neighbor.