ns2 project in Nevada
ns2 project in Nevada the client services class uses two types of classes for
communication between clients and agents and among
agents. The agentClient provides APIs to manage, control,
and send requests for an agent and it is ns2 project in Nevada used for direct
communication between the client and a given agent or
among agents. In addition, the agentGroup provides APIs to
manage, control, and send requests for a group of agents
using the agentClient to individually ns2 project in Nevada communicate information
to all agents in the group. For example, when a job is
initiated, the request and schedule objects are ns2 project in Nevada passed to the
agentGroup, which uses the agentClient to pass them to
individual agents. Both agentClient and agentGroup are also
used as API for developing distributed applications. When
a programming model is developed using the runtime
support environment, the interprocess ns2 project in Nevada communications are
handled in different ways. Point-to-point communications,
for example, can be implemented directly by the ns2 project in Nevada programming
model. However, if the nodes/machines involved are
not within a single cluster, the agents can assist ns2 project in Nevada the
communications by providing routing mechanisms between
the different nodes. In addition, group communications
such as broadcast and multicast can be provided by
the runtime environment rather than the programming
model to achieve efficient distribution and ns2 project in Nevada response times. The system allows multiple users to execute multiple jobs
simultaneously. To properly manage these jobs, each job
has multiple levels of identification, starting with a unique
job ID assigned by the system. The user ID and the program
name further distinguish different jobs. Within each job,
thread IDs are used to identify the remote threads of the job.
Executing user threads on remote machines ns2 project in Nevada exposes these
machines to many “alien” threats, raising security and
integrity concerns. Therefore, these machines must be
protected to ensure safe execution. Java’s default security
manager provides some level of protection by checking
operations against defined security policies ns2 project in Nevada before execution.
However, the security manager in Java has some
restrictions, thus many functions have been modified or
rewritten for our system. More specifically, two modes of
execution are used to provide a robust and secure
environment: 1. The Agent Mode in which no restrictions are
imposed. A thread running in this mode has full
control of all the resources and operations in the
system. All agents run in agent mode. 2. The User Mode in which restrictions are applied to
limit the user access to the system resources. Some
operations, such as deleting files, creating a ns2 project in Nevada subprocess,
using system calls, modifying system properties,
and writing files, are disabled in this mode.
With the security modes in place, the user processes have
full access to resources on their local machines (where the
user job was initiated), but limited and controlled access to
all remote machines’ resources (since they are running in
user mode). To provide users with access to necessary
resources for their application, the root (master) process
executes on the user’s local machine. However, the ns2 project in Nevada user has the option to override this setting and allow the root process
to execute on a remote machine; however, the application
will have limited access to the system’s resources.