A computer network, or simply a network, is a collection of computers and other hardware components interconnected by communication channels that allow sharing of resources and information.

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6answers
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Difference between a socket and a port

Could someone please explain quite clearly the difference between a port and a socket. I know that a port serves as a door into the network for an application process and that the application process ...
85
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4answers
39k views

IPv4 to IPv6. where is IPv5?

As all of us know that after IPv4 it came IPv6. How this transition happened? I just want to know was there any IPv5 also? or there is any other logic in naming this version of IP as IPv6?
21
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5answers
5k views

Why can't we use IP address instead of cookies in identifying the client in servlets?

I know we have some extra advantages in using the cookies over IP address, but my question is Why can't the container just remember the IP address of the client in identifying the client when he visit ...
14
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1answer
759 views

What did network programs use to communicate before sockets was invented (around 1983?)

Sockets were invented in Berkeley around 1983, but how did networked computer programs work before this? These days, pretty much everything uses sockets, so it's hard for me to imagine how else ...
11
votes
2answers
778 views

How to divide work to a network of computers?

Imagine a scenario as follows: Lets say you have a central computer which generates a lot of data. This data must go through some processing, which unfortunately takes longer than to generate. In ...
8
votes
4answers
991 views

How a port “listens”, pull or push?

When you write a code to listen from a port, like 80 for example, what happens under the hood? Is the method the OS uses to listen is pull, or push? In other words, does the OS checks that port every ...
4
votes
2answers
215 views

Why is it called network “topology”? Why not network “graph”?

I want to understand why we use the term "network topology" as opposed to "network graph", or another term, to talk about the structure of networks. I'm working on a network design for a project, and ...
4
votes
3answers
8k views

TCP and UDP basics: connecting to a website

I am just learning computer networks so please forgive me if this question is naive. I know the TCP protocol binds itself to a port till the transfer of messages is over (port 80) and UDP is best ...
4
votes
1answer
730 views

Is PGM (Pragmatic General Multicast) viable to achieve reliable message delivery with IP multicast?

I have a server application that distributes stock quotes to a number of clients on our internal network. As the number of clients has grown, unicast (TCP) connections between the server and the ...
3
votes
6answers
808 views

Is scanning the ports considered harmful? [closed]

If any application is scanning the ports of other machines, to find out whether any particular service/application is running, will it be considered harmful? Is this treated as hacking? How else can ...
3
votes
4answers
2k views

How can I work out how many IP addresses there are in a given range?

I'm wondering if there is a formula to work out the amount of IP addresses in a given range. I have a system that takes either a single IP address or a start and and end IP address: A single one ...
3
votes
2answers
289 views

Massive vehicular network simulator

I am interested in making a vehicular network simulator (vehicular network as in vehicles can be equipped with radios and when they come in range they can talk with each other). I want to be able to ...
3
votes
1answer
492 views

Which programming guidelines for a chess network application?

I'd like to implement a simple chess peer to peer network application : one instance of the program may register friends player, and when one friend is "connected" (I mean both available by another ...
3
votes
3answers
123 views

How can I architect P2P discovery?

I've never really done network programming so this is all new to me. What I'm attempting to make is a Peer to Peer "chat" client. The idea is that anyone can connect to someone whose IP they know. All ...
3
votes
1answer
940 views

What will generate an adjacency matrix file with a specified topology for me?

I am writing an application that takes some file specifying an adjacency matrix and uses this to construct a graph (in this case, a directed social network). What I would like to do is specify the ...
2
votes
2answers
169 views

Securing my own software… against myself?

I do a lot of programming work for other people's businesses. I am currently working on a project for my local Scouts group that I have worked with before. The problem is I have built them their ...
2
votes
1answer
59 views

Can udp packets be glued

Is there any standard that says that udp packets must not be combined together by operating system? In other words can I be sure that when I send small udp packets by sendto or analogues, I will ...
2
votes
2answers
799 views

Simplest possible Paxos algorithm (distributed consensus) explanation

I am looking for a simple explanation of the Paxos algorithm that can be used for reaching consensus in a distributed environment (possibly peer to peer network). Every explanation I have encountered ...
2
votes
3answers
5k views

Does data size in TCP/UDP make a difference on transmission time

While discussing the development of a network component for our game engine, a member of our team suggested that transmitting either 500 bytes or 1k of data using UDP makes no difference from ...
2
votes
1answer
191 views

Accessing internal API via Internal DMZ

I have an API that for firewall reasons can't sit on an internal DMZ and has to reside on the internal network. It was suggested that I build a 'shell' API that basically has all the same endpoints ...
2
votes
1answer
434 views

Pattern for mobile app data synchronisation using HTTP over 3G networks

I have a mobile app built using jquerymobile, PhoneGap and some custom CSS and JavaScript. The data objects are received in JSON and used to display different forms to the user. For example { id: 1, ...
1
vote
2answers
232 views

Estimating file transfer time over network?

I am transferring file from one server to another. So, to estimate the time it would take to transfer some GB's of file over the network, I am pinging to that IP and taking the average time. For ex: ...
1
vote
1answer
212 views

What is the most efficient way to discover devices on a network?

I've been programming a C web server from scratch as an interface for controlling ESP8266 WiFi modules that I plan to use to control appliances & lighting with relays. In an attempt to make a user-...
1
vote
2answers
348 views

Euclidean Space Fully Connected Nondirectional Graph: Shortest Path to all nodes

So this may be a question that is born of my inability to properly express my intentions to Google. In a fully connected non-directional graph such that any three points can be properly represented ...
1
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1answer
95 views

REST services with a local or remote application

I have several uncommon questions related to the design of REST services hosted on a server communicating with local or remote applications. As an example, let's say that I have 2 machines ("A" and "...
1
vote
1answer
286 views

Hardware-control on one computer. But how about several?

For a while I have been pondering the question of, given a standard interface specification, whether there is a way to allow multiple programs to control multiple hardware devices across the network. ...
1
vote
1answer
79 views

How to improve timeout value dynamically?

I'm working on an application where I want to keep a timeout value computed dynamically using a moving average of say 100 previous response times for service A. This value + some buffer (~3 seconds) ...
1
vote
0answers
30 views

Splitting the application into two different hosting providers

Due to cost I am currently thinking of using AWS for scalable hosting of the node.js backend of the application that would be nice to have monitoring,load balancing and all the goodies of the AWS ...
0
votes
1answer
354 views

Limitations of modern programming languages for low-level network programming [closed]

For say a network packet sniffer, are there any of the more modern high level languages such as C# or Java, that would actually be unsuitable or limiting when it would come to constructing a packet ...
0
votes
1answer
101 views

How best to implement a local-area peer to peer network

My goal: To write a program where any two computers on the same LAN see each other, and can talk directly to each other without any servers or accounts. Every client must be just as strong as every ...
0
votes
1answer
166 views

How to design resilient web service clients?

I am writing an app that is supposed to talk to a web service. Let's say it's a chat app. It would need to receive a stream of new messages (so that they are pushed to the interface as quickly as ...
0
votes
2answers
71 views

Connect PC application to a group of similar hardware devices, using TCP

Our company has started to design a system where many (typically 4 or 6) force-sensitive platforms, containing load-cells, would stream data to the PC via TCP. Each platform and the PC shall be ...
0
votes
1answer
584 views

What is a peer in computer network?

From Tanebaum's Computer Network: A five-layer network is illustrated in Fig. 1-13. The entities comprising the corresponding layers on different machines are called peers. The peers may be ...
0
votes
1answer
501 views

Socket connection to external IP through server

I am working on an application using sockets. Essentially I want to stream data between two clients. Since I can't connect the two clients together directly (they aren't on the same network), I will ...
0
votes
1answer
388 views

Design question on best option to store data on remote computers

I'm making a windows forms application which I want to install on a few computers that are all connected together on a network. Each of these computers have access to a number of servers on which ...
0
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0answers
21 views

Finding performance (network perspective) differences between mobile websites and their corresponding applications?

I'm researching performance differences when using an application, compared to its mobile website counterpart. To my help I looked into what other people define as performance(since it's a broad term) ...
0
votes
0answers
35 views

Qt network app sockets vs. QtNetwork library dilemma

I am working Qt network app which basically opens some sockets, for start, one QUdpScoket and one QTcpSocket. Now, through these two socket data stream is read and written to, that is all ok. However, ...
0
votes
0answers
101 views

File based communication vs Rest or RPC

My company make automation machines (with a PC inside and a custom built software to control it). So, for the purpose of this question, we can say that these are normal PCs. Sometimes we have the ...
0
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0answers
40 views

Project that has no network involve, how can I update multiple databases?

I am working on a project that involves a very large area, for example this area is a big subdivision with 10 gates, because it is so big and we are aiming on producing a low-cost product and creating ...
-1
votes
2answers
149 views

What interface does python use to implement sockets?

When I programmed in python, I believe I interfaced with the transport layer using sockets. If python was programmed by humans, they must have used an interface that was "lower" than sockets, to ...
-2
votes
0answers
27 views

Creating hostfiles [closed]

I am trying to run a c++ code in linux computer, but I get error about missing hostfile. I read some details about the hostfile, and I got that a hostfile that tells MPI where it is supposed to run ...
-2
votes
1answer
135 views

How can I have a shell script log into a remote server and execute imqcmd there? [closed]

I want to write a shell script to connect to the remote server and execute a command (any linux command). I am using linux and want to prepare a shell script which can login to the virtual directory ...