A GENERIC INTERFACE FOR SYSTEM AND APPLICATION MANAGEMENT
FIELD OF THE INVENTION
[0001] The present invention relates generally to field of system interface. More
specifically, the present invention is directed to sending and receiving data to and from a system.
BACKGROUND
[0002] Embedded systems are growing more and more complex, requiring a
range of external management applications such as SNMP, Command Line
Interfaces, TNM, WBEM, etc. These applications have completely different
interfaces, network protocols and purposes but must all interface to the low-level
internals of the system.
[0003] In order for a system to perform successfully in a user environment, it is
necessary that the user be able to configure the system to operate as desired, and
to be able to observe the device for troubleshooting and monitoring purposes.
Further, the system needs to be able to provide its configuration at any moment
and needs to be able to be restored to captured configuration. The configuration
may possibly be editted offline. This functionality is collectively known as
"management".
[0004] Management may be effected through a variety of user interfaces. The
most common is Command Line Interface (CLI), where configuration and display
commands are entered in text mode and promptly executed. Another common
interface is Simple Network Management Protocol (SNMP) where configuration - and monitoring data is transmitted over the network.
[0005] A technology currently in development by Sun Microsystems and various
partners is working towards a much broader and more abstract framework. JMX
(Java Management Extensions) is a Java based model for implementing management services independent of a management protocol. Sun's model is
much broader in scope and is also incomplete; the specifications are in an early
form of definition by the JMX community. JMX completely replaces the internal
applications with their own framework.
[0006] It would be advantageous to have an interface definition that allows
implementers of device drivers and low-levςl system services to provide
configurable attributes and statistics to the higher-level system management
applications without knowing anything about the system management
applications.
SUMMARY OF THE INVENTION
[0007] In one embodiment, method for providing a generic interface is disclosed. Data available in a system is identified. Each data is categorized as a scalar data
or a tabular data. The tabular data is associated with data from a table and the
scalar data is not. Each data is further categorized as a parameter data or a
statistic data. The statistic data is pulled from the system. The parameter data is either pulled from the system or pushed to the system. The data is grouped into
groups based on logical relationships of data in the groups. A blank form is
developed for each group of data. Each blank form has one or more fields
defined to accommodate the data in the group. Using the blank form, the data is
pushed to the system and pulled from the system.
BRIEF DESCRIPTION OF THE DRA INGS
[0008] The present invention is illustrated by way of example in the following drawings in which like references indicate similar elements. The following
drawings disclose various embodiments of the present invention for purposes of
illustration only and are not intended to limit the scope of the invention.
[0009] Figures 1A and IB provide exemplary illustrations of an Interface
Manager.
[0010] Figure 2 is an illustration of an exemplary hierarchy of forms and form
classes defined by the present invention.
[0011] Figure 3 is an exemplary illustration of three instances of a form.
[0012] Figure 4 is a table illustrating exemplary XML (Extensible Markup
Language) tags.
[0013] Figure 5 is an exemplary illustration of a push operation and an XML file
mapping the push operation.
[0014] Figure 6 is an exemplary illustration of a tree representation of an XML
document describing a CLOCK SET command.
[0015] Figure 7 is an exemplary illustration of a pull operation and an XML file
mapping the pull operation.
[0016] Figure 8 is an exemplary illustration of interfaces between the internal
manager, CLI and SNMP.
DETAILED DESCRIPTION
[0017] In one embodiment of the present invention, a method for providing a generic interface is disclosed. A framework is used for delivering data to and
from the system. The framework consists of different delivery vehicles or forms to carry different types of data.
[0018] The following detailed description sets forth numerous specific details to provide a thorough understanding of the invention. However, those of
ordinary skill in the art will appreciate that the invention may be practiced
without these specific details. In other instances, well-known methods,
procedures, protocols, components, algorithms, and circuits have not been
described in detail so as not to obscure the invention.
[0019] Generally, a system is managed by using high-level applications that
collect data from or send data to the system. The system may also be managed
by issuing commands using a command line interface (CLI).
[0020] In one embodiment of the present invention, a framework is provided for
system management that is abstracted from the low-level elements of the system
to be managed and the high-level applications that manage them. Collectively,
this framework is called the Internal Manager or IMGR of the system.
[0021] The IMGR performs as an abstraction layer between system implementation and system management applications independently of both
applications. The IMGR provides a generic interface for saving and restoring
system state. The IMGR also provides a generic interface that allows for the
retrieval of data (e.g., scalar and tabular data) from the system. For example, the
IMGR provides an interface definition that allows implementers of device drivers and low-level system services to provide configurable attributes and
statistics to the higher-level system management applications without knowing
anything about the system management applications. The IMGR also allows
system management application developers (e.g., CLI, SNMP, etc.) to work
autonomously, promoting code reuse and information hiding as well as
programmer productivity. In addition, the IMGR provides a uniform interface
across the system that can handle the complicated task of saving and restoring
system state.
[0022] The IMGR is a system wide construct that allows the low-level
developers of a system to provide access to data (e.g., parameters, statistics, etc.)
of the system without having any knowledge of the applications that will use
this data. It is a system wide abstraction layer, below which are kernel device
drivers and various system services software and above which are the
applications that provide management services. Using this framework,
applications can be insulated from the system implementation and vice versa.
[0023] Figures 1A and IB provide exemplary illustrations of an Interface
Manager. Referring to Figure 1A, the system 115 includes hardware
components, operating software, device drivers, etc. As described herein, a
range of different management applications is used to control and manage the
system 115.
[0024] In one embodiment, the IMGR 110 is created between the command line
interface (CLI) 105 and the low-level elements (e.g., kernel device drivers and various system services software, etc) of the system 115. The IMGR 110 lies between the user management (CLI, SNMP, etc.) and the operating software
and serves as an intermediary abstraction layer. The IMGR 110 operates to
provide translations of functions of the low-level elements in the system 115 to the CLI 105. Although the CLI 105 is used in this discussion, it would be
apparent to one skilled in the art that the description may also be applicable to
other management applications (e.g., SNMP application, etc.) at the same layer as the CLI 105, as illustrated in Figure IB.
[0025] The IMGR 110 defines an abstract interface and a framework gluing
internal applications (at the CLI 105) to the system 115 they are to manage. In
one embodiment, it is assumed that only data is conveyed between the IMGR
110 and the operating software in the system 105.
[0026] The IMGR 110 provides a representation of system data based on an
extensible interface that uses a notion of forms with special operations. These
forms can be "pulled" from the system to retrieve attributes such as system
settings and statistics or pushed into the system to handle configuration. The
IMGR 110 is based on object-oriented concepts requiring a programmer to
implement specific interfaces. These interfaces make available certain
operations to the managers such as, for example, the concept of a "GETNEXT"
operation that can be used on any table of meta-data to traverse its rows and columns irrespective of the underlying data type and bounds of the table. [0027] In one embodiment, the IMGR 110 includes a group of Java objects which are extensions of a base form object. Each form carries data. Both the
application layer (e.g., CLI layer 105) and system layer 115 (with its operating
software) are knowledgeable of particular editions of these forms, which are the basis of communications between these layers. In addition to carrying data, the
forms may also operate on the data they carry. For example, the form may
format the data for user presentation, or it may assist in traversing instances of a
table.
[0028] The data from the system 115 can be statistic data or parameter data.
Statistic data are data maintained by the operating software. Statistic data are
thus considered to be read-only from a management point of view. For
example, there is no SET type of operation for statistic data. Thus, statistic data
can only be pulled from the system. For example, a number of times the clock
has been read is considered a statistic data. Statistic data can also be considered
as counters maintained by the operating software.
[0029] As described above, data may be parameters or statistics. Data that is not
statistic data is considered parameter data. Individual parameter data may be
read-only (RO) or read-write (RW). Thus, all parameter data can be pulled and
some parameter data can be pushed. Referring to Figure IB, data sent from the
IMGR 110 to the system 115 is parameter data and not statistic data. However,
data sent from the system 115 to the IMGR 110 can be either statistic data or parameter data.
[0030] The base form object can be implemented as a data structure defined with one or more fields to carry the data to the system 115 or from the system 115.
Data are gouped onto the same form based on logical relationships of the data.
New forms can be added to accommodate different groupings of data. In one
embodiment, there is one operating software function for pulling (populating)
the form, and zero or one function for push the form. At the upper interface
(e.g., CLI layer 105), however, it may take several forms to satisfy a particular
CLI command.
[0031] In one embodiment, when a form is pulled (from the system), all
parameter data will be filled out by the operating software in the appropriate
fields. When a form is pushed (to the system), the operating software will look
only for those fields in the form which have the RW (read-write) attributes. For
example, a SETCLOCK operation involves pushing parameter data, while a
READCLOCK operation involves pulling parameter data. If information about
the number of times the clock has been read is required, a CLOCKREAD
operation would pull statistic, using a separate form. Thus, parameter data is
different from statistic data. Note that a form is merely a snapshot of data (or an
instance) at a particular time.
[0032] When a form carrying data from the system 115 is received by the IMGR
110, the IMGR 110 presents the form to the management applications or the CLI
105. In one embodiment, the data in the form are automatically formatted for
presentation to the CLI 105 or for presentation to the management applications at the CLI layer. Similarly, when the IMGR 110 presents a form to the operating software in the system 115, the data in the forms is presented according to an
appropriate data structure understood by the operating software. Thus, code
that places data in a form and code that extracts data from the form are
knowledgeable about a layout of the form such that the data in the form can be
consistently interpreted. In one embodiment, it is acceptable to have RO
parameter data and RW parameter data on the same form. Note that multiple
instances of the same form can be extracted with each instance possibly having
different data.
[0033] There may be multiple forms to carry different types of data with each
form used to carry one or more data. A form may be used to carry data in
response to different actions. For example, the same form may be used to carry
statistic data from the system 115 in response to different actions issued by the
CLI 105 or by the management applications. Similarly, the same form may be
used to carry parameter data from or to the system 115 for different actions.
There may be different forms for different commands.
[0034] A form may be pulled from the system 115 to gather system attributes
(e.g., system configurations, settings, statisistics, etc.). For example, a filled-out
form can be pulled up from the operating software as a result of a
GET/SHOW/ DISPLAY command from the CLI 105. A form may be pushed to
the system 115 to set system configuration. For example, parameter data
associated with a command SET /CONFIGURE is pushed in a form to the operating software in the system 115. There is a one-to-one correspondence
between a form and platform code that fills out or reacts to a form. Knowledge
of the different forms is required for the different push and pull operations
between the management applications/CLI 105 and the system 115. These forms form a basis of communication between the management
applications/CLI 105 and the system 115
[0035] Figure 2 is an exemplary illustration of hierarchy of forms and form
classes. In one embodiment, the interaction between the CLI 105 and the IMGR
110 is performed using commands in a command set. For example, the
command set may include a GET NEXT command that can be used to traverse
rows and columns of a table data structure. As described herein, each of the
commands in the command set is associated with a form and that there may be
multiple distinct forms.
[0036] Referring to Figure 2, a form 205 may be designed to work with a single
data ("scalar data") in a scalar entity class 210 or with a row of data in a table
("tabular data") in a table entry class 215. The data in the table entry class 215
may be further subclassed as parameter data 225 or statistic data 226. Similarly,
the scalar entity class 210 may be further subclassed as parameter data 227 or
statistic data 228. Thus, a form 205 may be categorized as one of the four
following abstract subclasses:
InternalManager - Table - Parameter
InternalManager - Table - Statistic
InternalManager - Scalar - Parameter
InternalManager - Scalar - Statistic.
The tabular data may be accessed as an instance. For example, the form may
correspond to exactly one row of the table, and rows of a table can be
differentiated by some combination of columns of the table. Different instances
of the same table can be used so that specific entries in the table can be located,
or so that the table can be traversed. In one embodiment, a form 205 cannot be
used to carry a mixed combination of scalar data and tabular data. In another
embodiment, a form 205 does not support tables within tables.
[0037] In one embodiment, the command set supported by the IMGR 110 should
at least have pull management commands for pulling statistic from the system
115. This allows for at least some monitoring capabilities. In another
embodiment, data originally placed on one form may be presented in multiple
forms. For example, data pulled from the system 115 to the IMGR 110 may be
placed on one form, but the IMGR 110 may extract the data from the one form
and place them onto multiple forms before they are presented to the management applications or the CLI 105. The operating software of the system
115 fills out the forms to be pulled from the system. The operating software of
the system 115 also processes forms pushed down to it by the IMGR 110.
[0038] In one embodiment, it is acceptable to have both parameter data and statistic data on the same form. Thus, a form may be a parameter form, a statistic form, or a parameter and statistic form. For example, an interface index
item might appear on the same form as an interface statistic data in order to
correlate the interface and the associated statistic data. The interface index item
may also appear on several forms carrying parameter and/or statistic data. In one embodiment, just because a data is on a parameter form, it isn't necessarily
settable, though other items on the same form might be settble. In one
embodiment, a speed of the interface may be settable, but not its identity. For
example, it is likely that statistic data would be pulled from the system
frequently and repetitively (e.g., for monitoring purpose), and as such, forms
used to carry statistic data may be handled differently for optimization.
[0039] Figure 3 is an exemplary illustration of three instances of a form.
Referring to Figure 3, the three instances 305, 310 and 315 of the same form 300
are received at three different times. Each instance provides a snap shot of the
data on the form 300 at a particular time. In one embodiment, each form is
timestamped when it is used to carry the data. The timestamp may be used to
compare how much a statistic data has changed since a previous pull operation.
For example, the instance 305 of the form 300 has a time stamp field 320. In one
embodiment, the instance 305 is stored so that it can be used to compare with a
next instance of the same form.
[0040] In one embodiment, a delta value is pulled rather than an absolute value.
For example, the instance 310 of the form 300 has a delta value 325. The delta value 325 indicates a differece from the absolute value 322 in the instance 305.
In another embodiment, for each pull operation, an indicator may be set on the
form to indicate to the system 115 that the fields on the form need to be updated
only when the system 115 has different values than the default startup values for those fields. When a pull operation is not successful, a "fail" condition may be returned to the management applications or to the CLI 105.
[0041] Each of the fields on a form may carry non-null values or null values. In
one embodiment, when there is a push operation, any fields on the form that
have null values may be disregarded by the system 115. The system 115 needs
to extract data from those fields that have non-null values. The non-null values
may or may not be acceptable by the system 115. For example, a non-null value
may be alphanumeric when the system 115 expects a numeric value. When this
occurs, error condition may be communicated by the system 115 to the
management applications or the CLI 105.
[00421 In another embodiment, each form may be associated with a "save" and a
"restore" function. For example, when the "save" function is invoked for a
particular form, data corresponding to the fields on that form are pulled from
the system 115. The data then sent to a destination (e.g., user, management
application, data file, etc.). When the "restore" function is invoked, the
previously saved data is placed into the appropriate form. The form is then
pushed down to the system 115. The data is then extracted from the form to complete the restore operation.
[0043] An instance of a form may have scalar data or it may have tabular data.
As described herein, when a form is used to carry tabular data, each instance of
the form carries one row of data from the table. An indicator may be sent along
with the form to provide information regarding where the row is in the table. It
is assumed that the table remains constant during the lifespan of the push or pull operations.
[0044] When a command associated with a pull operation (e.g., SHOW
command) is issued using the CLI 105, an interpreter resolves the command into
an object/method pair. The "object" is a glue that calls a static method in the
form class which in turn pulls an instance of the form up from the system 115
and generates display information back to the CLI 105. The form can also be
read by the method of the glue object.
[0045] When a command associated with a push operation (e.g., CONFIG
command) is issued using the CLI 105, the command can also be resolved to an
object/method pair. In this example, an empty instance of the form is created
and the command parameters are translated into settings of the fileds of the
form. The form is then pushed to the operating software in the system 115 to
effect the push operation.
[00461 When the IMGR 110 is used to interface with SNMP (as shown in Figure
IB), most of the SNMP code is automatically generated by an agent software
(e.g., AdventNet software from AdvenNet, Inc. of Pleasanton, California) when it interprets a Management Information Base (MIB) file. In one embodiment, lowest levels of this agent code are edited to effect the "instrumentation" part of SNMP operations. In one embodiment, when a GET command on an object is
processed by the runtime agent, a form containing the item is pulled up from
operating software, and the value of the data is read from the form. Similar
processing is performed for a GETNEXT command. GETFIRST and GETNEXT
functions are provided as static methods in the form. SET commands are also
handled one varbind at a time. In one embodiment, a new empty form is
created, set the varbind value into the form field, and push it down to the
operating software. SNMP may be used for monitoring.
[0047] The IMGR 110 expects the operating software to provide a static pull and
a static push function. In both cases, a reference to a form instance is passed as
an argument. In one embodiment, when the form is for a table, another
argument specifies the sequence number (not the instance) of the entry in the
table (the table is assumed to remain constant during the lifespan of the
operation).
[0048] In the case of pull operations, there is an additional flag argument
indicating that the operating software should only fill out the fields of the form
that have different values than the default startup values of the system. In the
case of push operations, any fields of the form that are null can be disregarded -
only the fields that are non-null need to be acted upon. The form provides
public methods for setting and getting the fields of the form. In one
embodiment, the same form can be used for push and pull operations. [0049] In one embodiment, "native" methods are used where the C code of the platform accesses the methods and fields of the Java class. In the pull direction
(from the system to the applications), the setter methods of the form object are
used to fill out the form, while in the push direction, the fields of the form are accessed directly. Other approaches include use of "exec" functions called from within the form, or via the reading of 'proc' files.
[0050] In one embodiment, FAIL indications are returned if the pull operations do not succeed. In the case of push operations, even though there may be
careful checking by SNMP and by CLI before pushing a form, there may be
situations that a pushed form might not be acceptable by the operating
software. A set of exceptions is provided for these situations.
[0051] Figure 4 is a table illustrating exemplary XML (Extensible Markup
Language) tags. The XML document can be viewed as a description document
providing descriptions about how to interpreret parameter data and statistic
data. Each tag occurs in the XML document as a <tagname>...</tagname>
combination. Attributes are enclosed in the tag fields with their values bounded
by a pair of double quotation marks such as, for example, <tagname
attribute="value">.
[0052] The <cli> tag 405 is the top-level element of the XML document. All
other tags are subtags of this top-level <cli> tag 405. This <cli> tag 405 has no
attributes and text inside the <cii> tag 405 is ignored. The <mode> tag 410 contains the mode of the management command. There should be only one <mode> tag 410 in the XML document. The <mode> tag 410 has a single
attribute which identifies the name of the mode such as, for examples, <mode
name='global'> or <mode name="exec">. The <command> tag 415 is the top-
level tag for a single command. It has no attributes and text inside the <command> tag 415 is ignored. The <command> tag 415 contains a single
<keyword> tag such as, for example,
<command>
<keyword text="show">
</keyword>
</command>.
The <keyword> tag 420 specifies the text of a command keyword in
the command set of the CLI such as, for example SHOW, ENABLE or
LOGOUT. The text is supplied by the single attribute "text". The keywords
may contain other <keyword> tags to specify subkeywords.
[0053] The <help> tag 425 specifies help information for the command / keyword. The <help> tag 425 has no attributes. The text enclosed by the <help>
tag 425 defines the help text for the outlying tag, i.e. for a keyword or argument.
One example of the help information follows: <keyword text="show"> <help>Show running system information </help>
<keyword text="clock">
</keyword> [0054] The <action> tag 430 specifies that there is a executable action for the enclosing keyword. For example, the action specified within the <action> tag
430 is carried out for the associated command when the carriage return is
presses. The "object" and "method" attributes of the <action> tag 430 specify an object and a method in the system by name. A collection of Java type
interfaces is created for the "objects" and "methods" that get invoked during
run-time. One example of the object and the method follows:
<action object="CliSystem" method="clock">
</action>.
[00551 The <arg> tag 435 defines an argument type for an <action> tag 430. The
<arg> tag 435 has no arguments and text in the <arg> tag 435 is ignored. A
single <type> tag or <help> tag may be inserted in the body of the <arg> tag
435. One example of the <arg> tag 435 follows:
<arg>
<type tjrpe=:"java.lang.String"></type>
<help>destination address or hostname</help>
</arg> [00561 The <type> tag 440 describes a Java type for input to the invocation of the
object, method pair specified by the <action> tag 430. The Java type name is
entered as a "type" attribute of the <type> tag 440. Other text in the body of the
<type> tag 440 other than those associated with the "type" attribute is ignored. [0057] In this example, XML is used to describe the command language. XML is advantageous because there are a lot of available XML tools (e.g., editor tool,
browser tool, etc.) for development. Although XML is used, one skilled in the
art would recognize that other generalized markup languages might also be
used to describe or map the management commands to the objects of the
system, where the objects are low-level functions implemented in the system.
[0058] Figure 5 is an exemplary illustration of a push operation and an XML
document mapping the push operation. The XML document 525 describes
statically all the keywords, arguements, and mapping from a CLOCK SET
command to action in the system that will cause the action corresponding to the
CLOCK SET command to be carried out. The CLOCK SET command is made
available to a user or a management application interfacing with the system
even though the system may not have the exact CLOCK SET command in its
own command set. The XML document 525 describes the hierarchy of the
CLOCK SET command keyword by keyword. Each command is associated with
an action defined as an "object" and a "method".
[0059] The command 505 illustrates the "help" feature by specifying the "?" as
part of the of command argument. This "help" feature is also illustrated in the command 510 and 515 to get additional information about the format (e.g., time,
month, year) of the CLOCK SET command. The command 420 illustrates a
complete CLOCK SET command with all the possible arguments or parameters specified. The XML document 525 describes the CLOCK SET command 505-520 using the XML tags described in Figure 4. At run-time, the command CLOCK
SET issued by the user or the management application is recognized by the
interpreter as corresponding to the command keyword CLOCK shown on line
527 and the keyword SET shown on line 528. There may be multiple command
keywords in the same XML document in addition to the CLOCK command.
The interpreter will parse the XML document 525 to determine if the command
is a valid command. In the current example, the help information requested in
the commands 505-515 is enclosed in the <help> tags on lines 530, 535, 540 and
545 respectively.
[0060] Depending on the format of each of the CLOCK SET commands 505-520,
a form containing information extracted from the arguments/ parameters of the
XML document 525 is pushed to the operating software at the lower-layer. The
operating software then executes the action specified by the "object" and
"method" attribute of the <action> tag shown on line 529. Results (i.e., statistical
data) associated with this action is then pulled up from the lower layer and
displayed to the user or presented to the management application in another
form.
[0061] Figure 6 is an exemplary illustration of a tree representation of an XML
document describing a CLOCK SET command. An XML document created
using the tags described in Figure 4 is translated into a tree format that can be
interpreted at run-time. The structure of the tree corresponds to the tags and
attrbutes in the XML document. The tree also contains all of the texts enclosed by any of the tags so that every piece of information in the XML document is reflected in the resulting tree. Each tree describes what the command is and
what the expected arguments /parameters are. In one embodiment, a Java
Document Object Model (DOM) library is used to parse the XML document into
a resulting tree or DOM tree. The DOM tree contains a collection of Java objects
that represent the tags, attributes, and text of the corresponding XML document.
The DOM tree in Figure 6 corresponds to the CLOCK SET command described
in the XML document 525 illustrated in Figure 5. Note that there are only two
keyword nodes 605, 610 corresponding to the keywords CLOCK and SET
respectively. Note also that there are four argument nodes 620-635 under the
action node 615. The four argument nodes 620-635 correspond to the
arguments for "time", "day of month", "month" and "year" of the CLOCK SET
command. The DOM tree and its collection of Java objects are translated into a
collection of Java run-time classes.
[0062] Figure 7 is an exemplary illustration of a pull operation and an XML
document mapping the pull operation. The pull operations in this example
include a SHOW CLOCK command 705 and a SHOW CLOCK DETAIL
command 710. The XML document 715 illustrates a description of the above
two commands 705 and 710 using XML keyword tags described in Figure 4.
The XML document 715 describes the SHOW CLOCK command using
keywords, sub-keywords, help text, arguments, and specification of actions to be carried out by the lower-layer operating software.
[0063] The XML document 715 is presented in its source format and is normally
compiled using an XML compiler so that it can be used by a run-time system.
When a user or a management application issues the command, the run-time
system performs object mapping, method mapping and the arguments / parameters are provided to the operating software of the system to carry out the
action. For example, when the command SHOW CLOCK 705 is issued, the run¬
time system executes the action associated with an object CLOCK and a method
SHOW, shown on line 720. When the command SHOW CLOCK DETAIL 710 is
issued, the run-time system executes the action associated with an object
CLOCK and a method SHOWDETAIL, as shown on line 725. The run-time
system invokes a collection of Java system interfaces corresponding to the object
and method specified in the action. The run-time system then collects data
(parameter data) from the system, put them in a form and presents the form to
the user or to the management application.
[0064] Using the method of the present invention, commands that are associated
with the system and that are used to control the system can be shielded from the
user. These commands can be described and expressed using a universal
description language such as, for example, XML. A set of common commands is
created by describing all of the commands associated with the system. For
example, XML can be used to create a new set of commands that describe
commands associated with a Lucent router such that the new set of command is
consistent with commands associated with routers from Cisco. One skilled in the art would recognize that commands for other vendors can also be
implemented. Using this method also shield the users from changes or version
upgrades applied to the operating software of the system. In addition, when a
new system is used, the commands can be made to be the same by describing and mapping the commands to the objects and methods of the new system.
Thus, as shown in Figures 1A and IB, by having the internal manager as the
middle layer, the command set available in the upper layer through the CLI is
independent of the system of the lower layer.
[00651 Figure 8 is an exemplary illustration of interfaces between the internal
manager, CLI and SNMP. The run-time versions of the commands described
using the generalized markup language such as, for example, XML, may be
stored in a command description file 802. When the user 801 enters a command,
the CLI 805 searches the command description file 802 for the corresponding
definition to carry out the command. The method of the present invention can
also be used in a network environment using, for example, simple network management protocol (SNMP) and management information base (MIB). MIB
modules specify targets of management operations. The MIB modules are
interpreted to identify the target of management operations. [0066] Instead the user or the management application issuing commands
through the CLI, management commands are issued using SNMP 810. SNMP
810 interfaces with the IMGR 110 to access information from the system 850. In
one embodiment, the IMGR 110 is divided into several IMGR packages 820, 825, and 830. Each of the IMGR packages 820, 825 and 830 corresponds to a group of related services provided by the system 850. For example, the services may be
grouped under IP routing, ATM routing, etc.
[0067] The IMGR package 825 transfers data between the system 850 and SNMP
using forms 815, as described above. The IMGR package 825 includes a client
interface 814, pullers 817 and pushers 816. When a command is issued by a uer
801 though the CLI 805, the command is sent to the appropriate IMGR package
825. For example, when the command is a SET CLOCK command, the CLI 805
sends the command to the IMGR package 825 because it recognizes that the
IMGR package 825 processes system related commands including the SET
CLOCK command. The CLI 825 is abie to make this recognition because, at an
earlier time, the client interface 814 in the IMGR package 825 was registered
with the CLI 805. This registration allows the client interface 814 to indicate to
the CLI 805 that the client interface 814 handles system related commands. The
client interface 814 is aware of the specific actions of the system 850.
[0068] The IMGR package 825 fills the form 815 with parameter data for push
operations. The IMGR package 825 may also use the form 815 to extract
parameter data and/ or statistic data using pull operations. For example, when
a GET operation is processed by the IMGR package 825, the form 815 containing
the appropriate data is pulled up from the system 850. The data is then read from the form 815 by the SNMP 810.
[0069] Consider the following example of the results of an SNMP GET operation:
.1.3.6.1.2.1.17.4.3.1.1.255.255.255.255.255.3 = ff ff ff ff ff 03
This can be rewritten as:
{DotldTpFdbTable}.{Macadress}.(255.255.255.255.255.3} = ff ff ff ff ff 03
And interpreted as:
The MAC address of the Fdb Table entry whose MAC address is
255.255.255.255.255.3 is ff:ff:ff:ff:ff:03
In this example, within the FdbEntry form, there is a field containing a
MacAdress object. Access methods are provided to provide the value of the
address in the two different schemas that SNMP requires: as a string
("255.255.255.255.255.3") as used for instancing an object, and as a 6-byte OCTET
STRING used for the value. Internally, the MacAddress is kept as a 6-element
integer array.
[0070] The GET operation described above can also be used to get a
configuration of the system 850. A blank form 815 is pushed to the system by
the pushers 816. Recognizing that the action is associated with a SAVE
operation, the operating software of the system 850 fills out the blank form with
configuration data. The filled-out form 815 is then pulled from the system 850
by the pullers 817. The configuration data may then be saved in a configuration
file 818 for a subsequent restore operation. In one embodiment, the
configuration file is saved in XML format. When a restore function is invoked, the configuration file 818 is processed into CLI command lines. The CLI command lines are fed back to the CLI 805.
[0071] From the above description and drawings, it will be understood by those
of ordinary skill in the art that the particular embodiments shown and described are for purposes of illustration only and are not intended to limit the scope of
the invention. Those of ordinary skill in the art will recognize that the invention
may be embodied in other specific forms without departing from its spirit or
essential characteristics. References to details of particular embodiments are not
intended to limit the scope of the claims.