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package com.sun.jmx.snmp;

This engine is conformant with the RFC 2571. It is the main object within an SNMP entity (agent, manager...). To an engine is associated an SnmpEngineId. Engine instantiation is based on a factory  SnmpEngineFactory. When an  SnmpEngine  is created, a User based Security Model (USM) is initialized. The security configuration is located in a text file.
The text file is read when the engine is created.
Note that the engine is not used when the agent is SNMPv1/SNMPv2 only.
 The USM configuration text file is remotely updatable using the USM Mib.
 User that are configured in the Usm text file are nonVolatile. 
 Usm Mib userEntry supported storage type values are : volatile or nonVolatile only. Other values are rejected and a wrongValue is returned) 

 volatile means that user entry is not flushed in security file 
 nonVolatile means that user entry is flushed in security file 
 If a nonVolatile row is set to be volatile, it will be not flushed in the file 
If a volatile row created from the UsmMib is set to nonVolatile, it will be flushed in the file (if the file exist and is writable otherwise an inconsistentValue is returned)

This API is a Sun Microsystems internal API  and is subject
to change without notice.
Since:
1.5/**
 * This engine is conformant with the RFC 2571. It is the main object within an SNMP entity (agent, manager...).
 * To an engine is associated an {@link SnmpEngineId}.
 * Engine instantiation is based on a factory {@link com.sun.jmx.snmp.SnmpEngineFactory  SnmpEngineFactory}.
 * When an <CODE> SnmpEngine </CODE> is created, a User based Security Model (USM) is initialized. The security configuration is located in a text file.
 * The text file is read when the engine is created.
 * <p>Note that the engine is not used when the agent is SNMPv1/SNMPv2 only.
<P> The USM configuration text file is remotely updatable using the USM Mib.</P>
<P> User that are configured in the Usm text file are nonVolatile. </P>
<P> Usm Mib userEntry supported storage type values are : volatile or nonVolatile only. Other values are rejected and a wrongValue is returned) </P>
<ul>
<li> volatile means that user entry is not flushed in security file </li>
<li> nonVolatile means that user entry is flushed in security file </li>
<li> If a nonVolatile row is set to be volatile, it will be not flushed in the file </li>
<li>If a volatile row created from the UsmMib is set to nonVolatile, it will be flushed in the file (if the file exist and is writable otherwise an inconsistentValue is returned)</li>
</ul>
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 * @since 1.5
 */
public interface SnmpEngine {
    
Gets the engine time in seconds. This is the time from the last reboot.
Returns:
The time from the last reboot./**
     * Gets the engine time in seconds. This is the time from the last reboot.
     * @return The time from the last reboot.
     */
    public int getEngineTime();
    
Gets the engine Id. This is unique for each engine.
Returns:
The engine Id object./**
     * Gets the engine Id. This is unique for each engine.
     * @return The engine Id object.
     */
    public SnmpEngineId getEngineId();

    
Gets the engine boot number. This is the number of time this engine has rebooted. Each time an SnmpEngine is instantiated, it will read this value in its Lcd, and store back the value incremented by one.
Returns:
The engine's number of reboot./**
     * Gets the engine boot number. This is the number of time this engine has rebooted. Each time an <CODE>SnmpEngine</CODE> is instantiated, it will read this value in its Lcd, and store back the value incremented by one.
     * @return The engine's number of reboot.
     */
    public int getEngineBoots();

    
Gets the Usm key handler.
Returns:
The key handler./**
     * Gets the Usm key handler.
     * @return The key handler.
     */
    public SnmpUsmKeyHandler getUsmKeyHandler();
}