Threads play a major role in applications programming today. For example, most Web servers are threaded, as are many Java GUI programs. Here are the major settings in which using threads has been founded convenient and/or efficient:
• Programs with asynchronous events:
Here the program must be ready for various events, but does not know the order in which they might occur. For example, in Sections 3.1 and 3.2, we have a network server connected to several clients. The server does not know from which client the next message will arrive. So, we have the server create a separate thread for each client, with each thread handling only its client.
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The EPICS toolkit consists of a set of software components with which Application Developers can create a control system. The basic component types are:
•OPI
Operator Interface. A UNIX- or NT-based workstation or PC which can run various EPICS tools—the “clients.”
•IOC
Input Output Controller. A VME/VXI-based chassis containing a Motorola 68K or PPC processor with various VME I/O modules for analog and digital signals, and for access to field buses such as Allen-Bradley, GPIB, CANbus or CAMAC.
•LAN
TCP/IP-based Local Area Network. A communication network which connects the IOCs and OPIs. EPICS provides a software com- ponent, Channel Access, which provides network transparent commu- nication between every client—such as OPI—and an arbitrary number of servers—such as IOC.
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Huntron Workstation software It is very helpful if you have a working knowledge of Microsoft Windows prior to using
Huntron Workstation.
You are allowed to create a backup copy of the software disk. Your purchase agreement allows for copies to be made for backup purposes only-copying for distribution or resale is strictly prohibited.
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We use the PICPgm Develop Software for writing our codes into the Flash Memory of the PIC Microcontroller. PICPgm is very good open source software for Windows. Works well with Windows 98, XP and Vista. It supports even our JDM based programmer circuit. Here is a Screenshot of the software as you open it (without connecting any hardware circuitry).
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Iptablesrocks was created to provide a publicly available, easy to understand guide and tutorial for the installation and configuration of iptables. Iptables is a linux package for managing IPv4 (and optionally IPv6) packet filtering and NAT (Network Address Translation). Iptables can be configured to function as a firewall, a NAT mechanism, a packet filter or all 3 at once. The diversity of capabilities possible with iptables makes it a secure, stable and economical alterative to hardware based firewalls and routers or costly 3rd party firewall software. Iptables can also serve as a rendundant firewall in conjunction with a hardware firewall, providing you with an extra layer of security. Iptablesrocks.org covers the installation of iptables in a Redhat environment, the syntax and structure associated with iptables and a collection a pre-configured iptables configurations for a variety of applications. This site is currently under development. Enjoy!

When running a typical web server, you need a firewall that is secure and offers protection, but you also need one that allows all needed traffic to be able to enter and leave the server so that your server’s day to day operations can carry on unimpeded. This particular iptables configuration does the following:
1. Uses the “mangle” portion of the table to effectively block and/or confuse most port scans. These rules deal address FIN,SYN,RST,PSH,ACK,URG FIN,PSH and URG methods.
2. Establishes a locked down and secure foundation by initially blocking all incoming, outgoing and forwarded packets COMPLETELY.
3. With all incoming packets dropped by default, it then grants incoming access to a select number of ports. These ports are ports that a typical web server might allow. Open inbound ports include: 20 & 21 (ftp), 22 (ssh), 25 (smtp), 53 (dns), 80 (http), 110 (pop), 143 (imap), 443 (https), 993 (imaps)
4. With all outbound packets dropped by default, it then grants outbound access to a select number of ports. These ports are posts that a typical web server might allow. Open outbound ports include: 20 & 21 (ftp), 22 (ssh), 25 (smtp), 43 (whois), 53 (dns), 80 (http), 110 (pop), 143 (imap), 443 (https), 993 (imaps)
5. Both inbound and outbound connections are required to be in a “related and established” state. The “related and established” state requirement will require you to add the “ip_conntrack_ftp” module into your server’s configuration. This is typically done with the following command: insmod ip_conntrack_ftp
6. ICMP packet types 3, 8 and 11 are dropped by default for all inbound traffic. This makes your server unpingable and reduces the chance of ping ICMP based attacks. Pings are allowed for all outbound traffic.
7. Unauthorized inbound and outbound traffic is logged.

Download pdf An iptables guide & tutorial

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The Tutorial is designed to help you get familiar with MeMate HVAC 2005. Simply follow the Tutorial and perform all of the steps in the same order as described here. The Tutorial will give you a general picture of MeMate philosophy, abilities, and approach to the system design. You can find additional information in the MeMate User Manual. It covers MeMate commands and features not mentioned in this Tutorial. With Tutorial, you will go through MeMate operations demonstrated in the MeMate Multimedia Demonstrations. You may want to view respective segments of the Demonstration before working with a particular step of the Tutorial.
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This paper provides an introduction to writing concurrent programs with “threads”. A threads facility allows you to write programs with multiple simultaneous points of execution, synchronizing through shared memory. The paper describes the basic thread and synchronization primitives, then for each primitive provides a tutorial on how to use it. The tutorial sections provide advice on the best ways to use the primitives, give warnings about what can go wrong and offer hints about how to avoid these pitfalls. The paper is aimed at experienced programmers who want to acquire practical expertise in writing concurrent programs. The programming language used is C#, but most of the tutorial applies equally well to other languages with thread support, such as Java.
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Whether teaching, training, or collaborating, the valuable information on your board can now be an integral part of your digital information environment. That information can be shared real time or on demand, viewed locally or remotely via the Internet, as printed pages or on-screen as stand-alone Ink files, or embedded in documents from your favorite software applications. The purpose of this manual is to provide you with a comprehensive understanding of the remarkable tool now in your possession through a detailed description of the varied and powerful features of your mimio system, from the most basic to the most elaborate. These features are made possible through the richness and power of the mimio software application.
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