C++ Multicast Example Linux

The standard input (stdin) device is the keyboard. Assign multiple IP addresses to single Network card in RPM based systems I tested this on CentOS 7 64 bit server edition. Programming examples are currently available for the following platforms:. HMAC can take most of the hash engine in order to hash your data with the secret key. If you’re posting something to help, at least post it right. Iperf is a tool to measure the bandwidth and the quality of a network link. It still seems that something is preventing the UDP message from leaving the PC on the send port (confirmed by. Interactive multicast implies that TV programs are sent only over transmitters where there are viewers, and that only the most popular programs are transmitted. Understanding PIM Source-Specific Mode, Source-Specific Multicast Groups Overview, Example: Configuring Source-Specific Multicast Groups with Any-Source Override, Example: Configuring an SSM-Only Domain, Example: Configuring PIM SSM on a Network, Example: Configuring SSM Mapping. Iperf is a very useful utility for network troubleshooting. It attempts to be compliant with RFCs 1889, 1890, 2038 and 2250. The biggest use of this utility is in the scripts where we need to deal with TCP/UDP sockets. Multicast is communication between a single sender and multiple receivers on a network. This page contains examples on basic concepts of C++ programming like: loops, functions, pointers, structures etc. Links to other multicast code examples. Default is 64. C++ Language These tutorials explain the C++ language from its basics up to the newest features introduced by C++11. GitHub Gist: instantly share code, notes, and snippets. The default iptables rules that come with most of the Enterprise Linux distributions (e. If for any element then given predicate returns true then it stops the further iteration and return true, else it returns false. Specify the IP time to live for unicast and multicast packets. c * This sample demonstrates a Windows multicast client that works with either * IPv4 or IPv6, depending on the multicast address given. c++ documentation: Semaphore C++ 11 Side by Side Comparisons of classic C++ examples solved via C++ vs C++11 vs C++14 vs C++17 GNU/Linux; opencv; Python. 8, the DOVE extensions have been added to the VXLAN implementation, removing the dependency on multicast. To create a standalone application which includes the "server" and "client" in the same program (and does not communicate with an external MySQL server), see Section 27. So in this tutorial we shall be checking out few examples of how to use netstat to find information about network connections and open ports on a system. This does not seem to be happening, so I want to make sure that the multicast UDP messages are getting through as my first step. Skip to content. 013 the all PIM routers, etc. All this special multicast groups are regularly published in the "Assigned Numbers" RFC. So let’s begin to summarize the difference between these three: Note: There is no separate classification for Many-to-Many applications, for example, video conferencing or online gaming, where. Tonight, I shifted RS232 serial port examples and the USB example for the PIC18F4550. Linux is an open-source operating system. All programs in this page are tested and verified. System: Windows Mac OS X Linux: Task: Features: Special characters Alternate languages Group names Some other Some other Some. dgram_echo. Was there anything special that you had to do? I can't seem to get it to send or receive a multicast. org are covered by this forum, too. The code is described in detail below. 1 which can be also a domain name like poftut. Because creating multicast tree is time consuming, it's pretty normal to lost first few multicast packets. HMAC can take most of the hash engine in order to hash your data with the secret key. 3 with gcc) and Windows (tested under Win2K with Visual C++ 6. Miscellaneous. Special addresses are defined for this purpose and are handled specially by network adapters, networking hardware, and IP stacks. This article gives some insight in to the tricks that you can do with AWK. cpp | hwclient. So in this tutorial we shall be checking out few examples of how to use netstat to find information about network connections and open ports on a system. The msg_flags field in the msghdr is set on return of recvmsg (). MulticastSocket-class. 3, “Writing C API Threaded Client Programs”. This will produce all tcp, udp & unix connections from the system. If I run the VI as is, with default values for 'Send to Port' and 'local port' it does not work. Any references found are resolved and the libraries are mapped into your program. Source Specific Multicast Example - Waikato Linux Users Group. A multicast address is specified by an IPv4 multicast address in its numeric representation. # touch file. The condition_variable class is a synchronization primitive that can be used to block a thread, or multiple threads at the same time, until another thread both modifies a shared variable (the condition), and notifies the condition_variable. IP_MULTICAST_TTL (since Linux 1. Together with anycast and unicast, multicast is one of the packet types in the Internet Protocol Version 6 ( IPv6 ). But now I need the receiver to run on Ubuntu 10. com said: I have a two systems and I am able to communicate both systems using udp server and client at both ends If you have a client-server networking architecture, you'd almost certainly. With that said, many of the existing MSDN ODBC C/C++ samples that are console based should compile on Linux with only minor modifications. The routing engine “knows” how to forward multicast messages, but Linux does not support the automatic updating of the routing tables by incoming IGMP reports. The tree is a tiny, cross-platform command-line program used to recursively list or display the content of a directory in a tree-like format. Most of the. Here is the Hello world program in C++. tgz archive files, also called “tarballs. Skilled system administrators can do much of their work using the built-in tools without having to install additional software. 265 [2xUKR_ENG]. The idea is to accumulate examples in there and use it as a quick reference. You can manage your connections to these machines from within Visual Studio. The solution also doesn't provide means to specify return types in signatures. Examples with awk: A short introduction. wav) and the Sun/NeXT format (. Most of the time, we don't care to specify a specific interface and can let the operating system use whatever it wants. Linux being a multi-user system uses permissions and ownership for security. Now, I am using Ubuntu Linux. 15 thoughts on “ Programming udp sockets in C on Linux ” Nathan. A multicast is received and processed by hosts which subscribe to the multicast group of the multicast. This class provides various methods for controlling the flow of multicast packets like setting the ttl, network interface to use etc, along with the major functions of joining and leaving a group. This page gives you access to all the complete and commented code listings. Clonezilla itself is licensed under the GNU General Public License (GPL) Version 2. You can determine the IP address or addresses of your Linux system by using the hostname, ifconfig, or ip commands. 2) Set or read the time-to-live value of outgoing multicast pack‐ ets for this socket. Finally, to the article Bottom Link to Netbeans C/C++ Development Article-Installation SetUp and Hello-World Example. C++ Language These tutorials explain the C++ language from its basics up to the newest features introduced by C++11. C Language Examples of IPv4 and IPv6 Raw Sockets for Linux I have recently been investigating raw socket programming in C for linux and I decided to provide a collection of routines I have prepared. For example, the time to live, identification, total length, and options in an IP packet are printed. I am a software engineer. Hi All, I have checked and filter for Multicast is as follows eth. A complete reference for writing makefiles from simple to advanced features. 1 interface. Ns is a discrete event simulator targeted at networking research. Multicast routing examples. Provide collection Swing controls. MultiCasting Code. It would place the data into the socket's buffer and return. This is where Integrated Development Environment (IDE) comes in picture. For this example and the following ones, a patch is needed for the ip command (to be included in 4. I use standard libraries on Linux in C++, I found several example of multi-cast that didn't work with me. ” This command has a large number of options, but you just need to remember a few letters to quickly create archives with tar. Introduction to C++11 Thread Library. Netstat is a command line utility that can be utilized to list out all the network (socket) connections on a method comparable to network connections, routing tables, interface records, masquerade connections, multicast memberships etc. The original post follows. That was the basic way of running a C++ program in Linux. The example below shows how the "-o" client option should be used to specify a per-packet overhead of 28 bytes, for UDP payloads of 100 bytes. This article will explain how to configure or disable iptables so client multicast applications can receive multicast packets. Hey Silver Moon, I’m a not a programmer but are very interested in electronics and making things automated. This may be configurable in the next version. MySQL Connector/C++ 1. The application will work however after I run the Labview shipped examples: UDP Multicast Receiver. The code used is C and tested on Linux Fedora OS The Linux socket and network programming on multicasting client-server with C program example. Above example generates 8 byte setsockopt call where fist for bytes defines multicast_group and second interface_ip. cd is a Linux command to change the directory/folder of the terminal's shell. Packet Sender is a free utility to for sending / receiving of network packets. Donahoo and Kenneth L. Toolkits based on cairo. This book starts where the basic C programming book leaves off. Abstract:. - Sat Apr 18, 2015 5:50 pm #14921 I've tried your sketch as well as several others related to UDP multicast on the 8266. Source Specific Multicast Example - Waikato Linux Users Group. In this example, the multicast group (225. Linux, by itself, doesn't support multicast routing, and you need to add something to the Linux device to support multicast routing. If you want to monitor or modify any. /intuition-listener. Provide collection Swing controls. Topics discussed include IP multicasting, supported protocol, FEC, reliable sender and receiver, multicasting in ATM and ample C program and code examples The Windows socket 2, Winsock 2, multicasting programming tutorials with C code and program examples. CGI ( Common gateway Interface ) is an interface between Web client and the web server that runs your CGI script/program. They can both be executed by different threads at the same time. System: Windows Mac OS X Linux: Task: Features: Special characters Alternate languages Group names Some other Some other Some. Send plain or colored UDP network text, then receive and view it instantly with a Freeware tool for Windows and Linux/Mac. Great example code. Welcome to the new Unreal Engine 4 Documentation site! We're working on lots of new features including a feedback system so you can tell us how we are doing. This may be configurable in the next version. I was preparing lab environment to test configuration of Source-Specific Multicast on Juniper SRX Equipment and needed a tool to generate and measure Source-Specific Multicast streams. The security protocol is important because it determines what tool you use to connect to the network. IP_MULTICAST_LOOP (since Linux 1. multicast client : simple multicast client that sends data on multicast group. Advanced file-access programming. Single netcat binary is enough for port scan and can be used for all operating systems like Windows, Linux, Unix, MacOS, BSD. All this special multicast groups are regularly published in the "Assigned Numbers" RFC. Java Project Tutorial - Make Login and Register Form Step by Step Using NetBeans And MySQL Database - Duration: 3:43:32. Source Specific Multicast (SSM) The multicast that you are probably familiar with (PIM sparse and dense mode) using IGMPv2 are also known as ASM (Any Source Multicast). It's designed to be used in very similar way as ping (8) and also has some features of the fping (8) command. This book is a must for any serious UNIX/Linux programmer. Hi! I have a quick question. vi; UDP Multcast Sender. The program output is also shown below. You can find user communities also in irc. EDIT : Fixed the code based on above comment, binding to multicast address, stored in 'group', as opposed to INADDR_ANY to receive only multicast packets sent to multicast address. The addresses for multicast, called multicast groups, are a subset of regular IPv4 address range (224. vi; I have rebuilt the tests using examples from Labview 2015 (UDP read and UDP write) with the same result. OSX (for unknown reasons) will not receive any multicast data if bound to a specific interface, so it has to use ‘0. , cache profiling); however, here we focus on the default tool, memcheck. MulticastSocket-class. I arbitrarily picked 239. In order to Join multicast group Python uses native OS socket interface. This example demonstrates how to integrate CUDA into an existing C++ application, i. Lawlor Here's how you write an entire function in assembly. Enter this command: ifconfig [nic]:0 [IP-Address] netmask [mask] up An example is shown below. A multicast is received and processed by hosts which subscribe to the multicast group of the multicast. If you need to download Linux drivers, you will be directed to a website that is outside HP Customer Support. 1, Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, Windows Server Technical Preview, Windows Vista. I have scripts that run IP multicast tests; however, my scripts are failing on a particular linux machine. Parts of the code (fec. Zeroconf Multicast Address Allocation Protocol (ZMAAP) (draft-ietf-zeroconf-zmaap-02. Multicast delegate passed as a parameter (C++) 0 Hi, I have a dynamic multicast delegate declared in c++ and I will like to have a function, callable in blueprint, that takes in this dynamic multicast delegate as a paremeter. txt) which represents captured network data. Example: For Java 8u79 replace 8u73 with 8u79. Finally, to the article Bottom Link to Netbeans C/C++ Development Article-Installation SetUp and Hello-World Example. Below is the source code and errata from the book "Multicast Sockets: Practical Guide for Programmers". This tutorial demonstrates how to build or develop the multicast server applications using Linux socket API. UNIX Socket FAQ. The kernel functions implementing this technology are also shown, to complete the global view of the multicast support under Linux. By Rafnas T P in Articles Oct. The find command is one of the most essential commands on the linux terminal, that enables searching of files very easy. You might want multicast features, but if your Linux box is not going to act as a multicast router you will probably not want multicast router features included in your new kernel. These tutorials cover a wide range of C and C++ programming for both opensource and commercial. The set_multicast_list function performs some hardware-specific actions at the driver level so the network card will be able to receive packages sent to this specific MAC address. The command line is one of the most powerful features of Linux. Each device processes the query and responds if the request filter is satisfied. C++ Shell, 2014-2015. Example Commands. Previously to the switch, a test is made to determine whether the options are multicast router specific, and if so, they are routed to the ip_mroute_setsockopt() and ip_mroute_getsockopt() functions (file LINUX/net/ipv4/ipmr. That is, we have to ask the kernel to "join" those multicast groups. Lawlor Here's how you write an entire function in assembly. However, if I set the two controls to contain the same portnumber it works on my Win10 - also after reboot and with out having run UDB Multicast example before. Become root by running su and entering the super-user password. c then run with the command. Linux C++ Socket Example with Client Server and Mulit-T - The aim of this Linux C++ example is to create simple client/server socket communication and multi-threading program on Linux. NET as well as the method in which multicasting works and why it is useful now and how, with the increasing availability of bandwidth and the increased use of streaming media, will become a definitive. This example is not multithreaded. It attempts to be compliant with RFCs 1889, 1890, 2038 and 2250. In this example, we will scan IP address 192. This property cannot be set for a transactional queue. IPv6 Site-local unicast local IPv4 to IPv6 6bone (for backbone research). Motivation: I needed a page like this when working with a small test program for my master's thesis at Appius / Fält Communications. In the case of CoAP, a 'get' request is sent via multicast to all IoTivity devices. This is a simple educational example of an IPv4/IPv6 multicast client and server, running under UNIX and Win32. Several extensions to the programming API are needed in order to support multicast. Code Examples. Three asynchronous multicast callback implementations are available: Two in C++ and one written in C. Consider the example of a heterogeneous Layer 2 and Layer 3 network that does not use IGMP snooping. This example demonstrates how to integrate CUDA into an existing C++ application, i. These two together create the cluster separation. There are a few tcpdump command with examples that i will share with you. The mechanism is different for Bluetooth, SSDP/HTTP, etc. The following line should work:. \What beautiful colours\, I say, and you agree. There is a better way to develop a C++ based application in Linux, using IDE. In this tutorial, let us use the following example: eth0 has been configured with IP address 19. dvbstream is a popular utility, from the "DVB tools" project, that can be used to broadcast either a (subset of a) DVB transport stream or a DVB program stream over a LAN using the rtp protocol. Several extensions to the programming API are needed in order to support multicast. For example, host C can answer host B’s DAD queries (below at 8. For some use-cases, in particular link-local multicast, it may not be possible to use multicast routing, then I recommend trying out: Bridging networks, see bridge(8) or Linux bridge - how it works igmproxy, mcproxy, or OpenVPN in Layer-2, bridged mode Make sure to check out the FAQ for the most common problems. c * This sample demonstrates a Windows multicast client that works with either * IPv4 or IPv6, depending on the multicast address given. Refer to the diagram below: When the multicast source starts to send multicast traffic for a multicast group, the switch probably has not seen any IGMP requests to join the multicast group, so the multicast. If you want to monitor or modify any. A friend of mine has been asked if he can multicast a local conference, across the internet to several remote towns. November 29, 2017 at 6:06 pm. Currently I'm testing on another server that has. In our example, the security policy allows multicast packets received by the internal interface to exit to the external interface. This tutorial will create two C++ example files which will compile and run in Ubuntu environment. 94 and bound to group ip 226. Whether you've had any prior programming experience or not, the tutorials on this site will walk you through all the steps to write, compile, and debug your C++ programs, all with plenty of examples. WebRTC Scalable Broadcasting. Even though the multicast packets are forwarded to all interfaces, you must add security policies to actually allow multicast packets through the FortiGate. Driver support for Linux OS For Linux downloads, HP recommends another website. agetty It is a Linux version of getty, which is a Unix program running on a host computer that manages physical or virtual terminals to allow multi-user access alias Instructs the shell to replace one string with another string while executing the commands amixer It is a command-line mixer for ALSA. Compilers Required: Linux: gcc 4. Linux Lite has been in existence since 2012. This book starts where the basic C programming book leaves off. This corresponds to a multicast IP and therefore is a multicast packet. txt) defines how IP hosts can allocate multicast addresses in the absence of outside configuration information. Doxygen usage example (for C)¶ I have been using Doxygen for a while now, but I keep forgetting bit and pieces of it. 100 and the vlan id is 100. These communicate using stream sockets in the Internet domain. Linux IP Networking A Guide to the Implementation and Modification of the Linux Protocol Stack Glenn Herrin TR 00-04. If invoked with one argument, it sends a packet containing the current time to an arbitrarily chosen multicast group and UDP port. Unicast with static flooding⚓︎ 3. Multicast has become a buzzword more than once in history. the CUDA entry point on host side is only a function which is called from C++ code and only the file containing this function is compiled with nvcc. That was the basic way of running a C++ program in Linux. How to configure multicast on an IP address (interface) - The Geek Diary Skip to primary navigation. See the screenshot of the running Java server (IP assignment utility) and the C/Linux client in the serial console window. There are three user types on a Linux system viz. 0 to Proxmox VE 5. This book travels. pcap as it can be read by any network protocol analyzer. sk****@gmail. Avahi is a free Zero-configuration networking (zeroconf) implementation, including a system for multicast DNS/DNS-SD service discovery. M Series,MX Series,T Series,QFabric System,QFX Series,SRX Series. An IGMP member report will be sent this addresses when a host joins a multicast group, then the multicast router can receive. You can determine the IP address or addresses of your Linux system by using the hostname, ifconfig, or ip commands. IPV6_MULTICAST_LOOP Control whether the socket sees multicast packets that it has send itself. I have scripts that run IP multicast tests; however, my scripts are failing on a particular linux machine. IP Multicast Addressing (Page 2 of 2) Well-Known Multicast Addresses. 2 netmask 255. dst[0] & 1 What I can interpret is to check [0]-->Least. Sample C++ Application: Retrieving KVP data from Hyper-V on a Linux Guest. Note that the message identifier is the same for each copy of the message. The code is described in detail below. They should be more thought of as an identifier rather than some unique address as we think of with IP. I made a Windows console application in C++. IPv6 multicast. /* multicast. Some examples of IP multicast addresses:. This website provides a comprehensive collection of computer networking tutorials, notes and study guides for anyone who is preparing for networking certificate or working in computer networking field. For example, a very simple client/server application for Linux, that is using UDP sockets. The new C++ language features also offers plenty of opportunities for new approaches. See the References section for the two other related articles. C++ does not contain any built-in support for multithreaded applications. Download if you are new to Oracle and want to try some of the examples presented in the Documentation Oracle Database 19c Client (19. If a large number of such multicast packets are sent from the network side, the air interfaces may be congested. 255) reserved for multicast traffic. 1 hour ago · Ilya Ilin (Kazakhstan), Men's 94kg weightlifting David Brooks and Ethan Ampadu are perhaps the most obvious examples, both firmly part of Ryan Giggs' plans having either played for England's age-grade sides or been heavily courted by them. While learning any programming language, practicing the language with examples will help you to understand the concepts better. 100 and the vlan id is 100. Surprisingly, there are very few resources on the Internet for multicast programming under WinSock and I think that this class that I wrote for my project will come in handy. I know that I can look at CONFIG_IP_MULTICAST in the kernel configuration file to determine whether the kernel was compiled with this. It is the IP-specific form of multicast and is used for streaming media and other network applications. The msg_flags field in the msghdr is set on return of recvmsg (). tgz archive files, also called “tarballs. This example is not multithreaded. Actually, Valgrind is a wrapper around a collection of tools that do many other things (e. He's baffled and has asked me for help. Are the C functions recvfrom and sendto mutually exclusive? No. Programming examples are currently available for the following platforms:. « Thread-Safe Queue (C++ implementation on Linux) Producer-Consumer Problem Solution On Self-Defined Semaphore (C++ implementation on Linux) » Leave a Reply Cancel reply. I am a software engineer. tar -rw-r--r--. Call MQSendMessage to send a copy of the message to each opened queue. Mixing Assembly and C++ Code CS 301 Lecture, Dr. Each OS takes an interrupt, and passes the packet on for inspection, which normally involves some data copies. These two together create the cluster separation. Example of Client-Server Program in C (Using Sockets and TCP) Below you’ll find an example of a very simple client-server program in C. the list contain C++ language basic and simple source codes and examples. Skilled system administrators can do much of their work using the built-in tools without having to install additional software. You need to pic an appropriate one for your setup. Here's an example in C++:. Whether you've had any prior programming experience or not, the tutorials on this site will walk you through all the steps to write, compile, and debug your C++ programs, all with plenty of examples. An example would be linking a function that saves data to a "Save" button on the interface. So let’s begin to summarize the difference between these three: Note: There is no separate classification for Many-to-Many applications, for example, video conferencing or online gaming, where. txt # ls -lh file. Computer Programming - C++ Programming Language - Games Sample Codes - Build a C++ Program with C++ Code Examples - Learn C++ Programming. It is maintained and funded by Offensive Security. dst[0] & 1 and understand that this corresponds to checking least significant bit of first address byte set. Sample code. --mcast-rdv-address address Uses a non-standard multicast address for the control connection (which is used by the sender and receivers to "find" each other). This book is a must for any serious UNIX/Linux programmer. Linux Netstat Commands with Basic and Advanced Examples August 6, 2018 Updated May 11, 2019 By Nishali Wijesinghe LINUX HOWTO Netstat is a command line tool that is used to view and monitor network statistics and configurations of a system. These tutorials cover a wide range of C and C++ programming for both opensource and commercial. The biggest use of this utility is in the scripts where we need to deal with TCP/UDP sockets. Last line has additional information (seq>=2 %0) which means, that after receiving first multicast packet with seq number 2, no other multicast packet was lost. This is a connectivity test, not a load test, each instance will by default only transmit a single multicast packet once every two seconds. Source code to display a sentence in C++ programming A simple C++ program to display "Hello, World!" on the screen. Introduction. We recommend using the latest version of a fast moving distribution such as Fedora, Ubuntu (non-LTS), Debian sid or OpenSuse to get a recent GStreamer release. #include /* for fprintf() */ #include /* for socket(), connect(), send(), and recv() */ #include /* for sockaddr_in and inet_addr() */ #include /* for atoi() and exit. Linux ifconfig command help, examples, and information. Java Multicasting Example Here follows a short description of how to write a multicasting application in Java using the sun. * Requires Windows XP+/Use MSVC and platform SDK to compile. Then point to multicast IP address 224. Linux C/C++ fork Example If you ever wanted to do multiple tasks at the same time in your C/C++ program then Linux fork () system call function is for you. 1 hour ago · Ilya Ilin (Kazakhstan), Men's 94kg weightlifting David Brooks and Ethan Ampadu are perhaps the most obvious examples, both firmly part of Ryan Giggs' plans having either played for England's age-grade sides or been heavily courted by them. To do so, the protocol, which is a member of the Internet Protocol family, provides various message types with which the hosts can inform the local router about the request to join and routers can receive and. NET, JavaScript, and C++. This tutorial demonstrates how to build or develop the multicast server applications using Linux socket API. This is fine if the data is going to a known server on your network. In the third case where the LAN has IGMP aware switches, and IGMP support is enabled, multicast packets will be transmitted only on segments where hosts have requested it. C / C++ Forums on Bytes. We point VLC to do announcements of this stream using SAP (see service advertisements protocol), set description of the streaming group to Video, and name this stream 'Jumper Movie'. Linux being a multi-user system uses permissions and ownership for security. You are here: Programming->C/C++ Sockets Tutorial This is a simple tutorial on using sockets for interprocess communication. HMAC can take most of the hash engine in order to hash your data with the secret key. Most notably, however, is simply that it is not the Linux team's responsibility to defend their use of C over C++ -- given the amount of code that must be adapted, it is more appropriate for the C++ devs to argue what heavy benefits C++ has in its favor (such that they merit the transformation of a complex and significantly large body of code). rcv field can also be formatted like. I like playing video games & reading books. Become root by running su and entering the super-user password. This article gives some insight in to the tricks that you can do with AWK. Simple C++ class example using serial port, USB, wireless… This post is part of the Practical C++ programming tutorial for Bioloid Here you can find a post serie about using serial port communications with C/C++ and C#, for Windows, Linux and microcontrollers. Instant Configuration. It is the C programmers guide to programming on the UNIX platform. This is the basis for cluster communications in Proxmox VE 2. Unicast with static flooding⚓︎ 3. Example Uses of Function Pointers Functions as Arguments to Other Functions If you were to write a sort routine, you might want to allow the function's caller to choose the order in which the data is sorted; some programmers might need to sort the data in ascending order, others might prefer descending order while still others may want something similar to but not quite like one of those choices.