In computer networking and computer science, bandwidth, network bandwidth, data bandwidth, or digital bandwidth is a measure of available or consumed data communication resources expressed in bits/second or multiples of it (kilobits/s, megabits/s etc.).

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Is there a linux terminal command that lets you see the amount of data coming in to your tcp connections in real time?

It would be something similar to top, where you see your cpu processes in real time. I'm not looking for a GUI like Wireshark to do it.
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Technologies that allow YouTube scale distribution?

Youtube as we know, is massive. It has thousand of concurrent users streaming at least 2 megabytes per video. Obviously, that gets to be a lot of traffic... far too much for any one server. What ...
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how can I limit per user bandwidth?

To summarise: I have a dedicated server with a few friends running a torrent client with web gui. Each user is running a client under their username on the server so downloads go in their user dir, ...
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Dynamically blocking excessive HTTP bandwidth use?

We were a little surprised to see this on our Cacti graphs for June 4 web traffic: We ran Log Parser on our IIS logs and it turns out this was a perfect storm of Yahoo and Google bots indexing us.. ...
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What is the best way to transfer a single large file over a high-speed, high-latency WAN link?

This looks related to this one, but it's somewhat different. There is this WAN link between two company sites, and we need to transfer a single very large file (Oracle dump, ~160 GB). We've got full ...
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Connecting two desktop switches with more than one cable?

I was hoping to find a way to increase bandwidth between two desktop switches I have, and I wondered if connecting them with two cables (or perhaps three) instead of just one might increase ...
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Who's using our bandwidth?

I can see from our ISP stats that a large amount of bandwidth is being used throughout the day, I suspect it's someone using our wireless router although I'm not definite. Our PC's all run various ...
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330 views

What are the different classes of Internet Connection and how do they differ?

I'm looking for the technical differences between consumer and professional Internet connections. By "professional" I mean: The kind you can get at a datacenter The kind you can get at an office ...
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How to Monitor Bandwidth usage in real terms

I have a small (windows) network with a few people on it. We have internet access via a BT router Generally things are all fine, but occasionally, we seem to experience a dramatic loss of ...
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If I send data to my computer using its public hostname, does it actually go over the internet?

To clarify: I'm using my public hostname to connect to a MySQL database. The hostname resolves to my server's external IP (e.g. 1.2.3.4). Is the data I'm sending/receiving via the MySQL connection ...
11
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9answers
791 views

Opinions on hosting servers in-house

I've read a half-dozen threads here about the pros and cons of hosting in-house, but our situation is a little different than most, so I figured I'd just open a new question. In short, we're a small ...
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How can I see how much bandwidth each Apache Virtual Host is using?

I have Apache set up to serve several Virtual Hosts, and I would like to see how much bandwidth each site uses. I can see how much the entire server uses, but I would like more detailed reports. ...
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Apache: Limit the Number of Requests/Traffic per IP?

I would like to only allow one IP to use up to, say 1GB, of traffic per day, and if that limit is exceeded, all requests from that IP are then dropped until the next day. However, a more simple ...
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8answers
643 views

Network explanation: megabytes or megabits?

I'm getting confused with network terms. Can you explain to me how I calculate network bandwidth? When people say 20Gbps does it mean 2.5 G bytes? I really need to understand what it means when a ...
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Rate-limiting incoming traffic

I've never quite understood whether or not it's possible to rate-limit incoming traffic. I realize that there is no direct method whereby to control the remote server's rate of sending packets (unless ...
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Monitor Internet bandwidth

We have an IPCop firewall/proxy installed in our network, and although I can use iftop to somewhat take a look at how the clients are using the Internet, is it possible to monitor it from outside the ...
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Monitor SSH-traffic per user

We have a backup application that runs once every 12 hours. Multiple servers, desktops, and laptops connect to an EC2-instance and push a backup via SFTP using their own log-in credentials. If they ...
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2answers
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How to find process which uses most bandwidth

How can I find the process which uses most bandwidth on a Linux PC? With iftop it's possible to find which connections produce most bandwidth, but how to find the process?
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Limiting network throughput of an already launched process ? (Linux/FreeBSD)

Is there any utility to limit the network throughput of a process after it has been launched? Simple example: you note that a user takes all your upload bandwidth using scp and you'd like to limit the ...
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Slow network speeds - what should I check?

Users are reporting that it's taking a long time to access files on the network, browse intranet sites, etc. What should I check?
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Best way to load balance across multiple static file servers for even an bandwidth distribution?

First off, I'll explain my situation to you. I'm running a fairly popular website as a side project, so I can't really invest a ton of money into it. I currently have just one server with HAProxy in ...
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2answers
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Bandwidth limits for Amazon EC2

I have a micro instance on Amazon EC2 cloud. Also the instance is small and it has vary low CPU and EAM usage but it generates a lot of content, so it can be considered like a web server serving ...
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How should I manage per-user bandwidth?

Users often run bandwidth intensive applications - peer-to-peer applications, video, etc. Do you monitor and/or cap per-user bandwidth?
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What limits the performance of scp?

I've two Debian Linux machine connected via 1 Gbit LAN. I can measure this with a raw HTTP file transfer with wget which gets around 100MB/s in either direction. When I now use scp, the maximum ...
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Limit VMware Virtual Ethernet bandwidth

I'm looking to simulate a 56KB modem connection in a VMware Workstation virtual machine. I remember reading this was possible, but forgot how?
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Somebody eating all our bandwidth, what should I do?

OK, this is frustrating, my site got thousands of page views/connections in the last 3 days and finally we ran out of monthly bandwidth. We bought more bandwidth and closed the site for maintenance. ...
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1answer
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Are network switch data transfer speed limits per port or per device?

Sorry in advance for the newbie question! When network switches report speeds of say 100 Mbit or 1 Gbit, are they referring to the maximum speed per Ethernet port or is this the physical limit of the ...
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Remote file copy util (like rsync) but that will take account of data already copied (in this session)?

Let's say I have a directory with 2 files, both are identical and quite large (e.g. 2GB ea.) I want to rsync that directory to a remote host. As I understand it (and I could be wrong), rsync ...
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4answers
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Limit SSH traffic?

I would like to be able to limit SSH bandwidth on my server. I.e. each sshd process should be limited to 200Kb/s or something like that. scp has this functionality, but ssh, being more designed for ...
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6answers
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Expected throughput in Gigabit network

I've been doing some tests with iperf to measure the network throughput between 2 servers (connected back-to-back thru a crossover cable) and I only see 180 to 200 Mbps. I tried different cables and ...
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Alternative to mod_throttle

Is there any alternatives to mod_throttle in apache2 ? Currently this module has been closed http://www.snert.com/Software/apache.htm.
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How much traffic can one machine generate?

Can just one machine on our network generate enough network traffic, whether it be from malware or P2P or whatever, to affect all network/internet users? My company has many public machines available ...
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1answer
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AWS, Bandwidth and content delivery

My question is about Virtual Machines and delivering their content over the servers connection to the internet. I have an Ec2 windows instance, and that instances network connection appears to be ...
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Best bandwidth tests to use in a pinch?

I see many tools that have been discussed for 'proper' bandwidth monitoring and testing - but I am wondering what people use 'in a pinch'? Particularly on systems that they may not easily have admin ...
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How do ISPs/Colocation Facilities limit bandwidth for Ethernet Drops?

I have switch providers and have run into some problems with bandwidth limitations. I have more bandwidth then before, but there are performance issues. The router is connected to a 100mBit port, ...
5
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1answer
375 views

What outbound HTTP throttling solutions exist?

I am looking for a way to flexibly manage outbound HTTP/HTTPS traffic in a way that respect site policies, and could be deployed at the "edge" of our datacenter network. For example, we use several ...
5
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1answer
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Command line speed test

There are several sites that give you decent speedtest metrics (DSLReports, Speakeasy; PhonePower even has additional VoIP-related metrics). I want to get these metrics on a periodic basis. Ideally, I ...
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2answers
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Insufficient channel capacity of 1GBit

There is a Caching Server (Varnish): it receives data from Amazon S3 on request, saves it for some time and gives it to the client. We have encountered the problem of insufficient channel capacity of ...
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1answer
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Limit incoming and outgoing bandwidth and latency in linux

I realise many similar questions have already been asked, but so far I've yet to find a solution to my problem. I have a virtual linux server (running Debian Squeeze) that I use for testing of ...
5
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1answer
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Ninety-Fifth Percentile Calculation for Bandwidth

I am trying to calculate the bandwidth of my current internet connection. I am pulling the current input and output transfer rate via snmp. If the argument to the following function is a sorted ...
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Measure bandwidth usage (GB's transferred) on a linux server

I have a linux email server that I am thinking about moving into "the cloud". After investigating the pricing I see that my major cost is going to be in bandwidth. How would you guys suggest measuring ...
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finding the best network latency between two countries

I know there are many tools to test for bandwidth and latency, but they all rely on having at least one host from which you can run those tests. I wonder whether there's an online source or some ...
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Real-time traffic monitoring router / firewall device

I'm looking for a router & firewall device that will provide built-in bandwidth monitoring; meaning, I go to the web control panel for the device and I can see a real-time breakdown of how much ...
4
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2answers
331 views

maximum download limit

I'm writing software for bandwidth management in Linux. I use TC for bandwidth shaping, and it worked fine. I want to limit user bandwidth for a period of time. For example: For user 1, 100MB in a ...
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3answers
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Do multiple network connections between switches increase bandwidth?

Say I have 2 identical unmanaged gigabit switches on a network, A and B. There are computers connected to switch A, there are other computers connected to switch B. A and B are connected via 1 ...
4
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2answers
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Mysterious Bandwidth Usage

We use a SonicWall NSA 3500 as our main router. We have a SonicWall Analyzer virtual appliance too that takes information from the NSA 3500 and determines all kinds of stuff, such as bandwidth usage. ...
4
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2answers
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Is there a linux command/tool that will provide end-to-end bandwidth information between local and external host?

CentOS 5.x At times, I've wanted to know what general bandwidth constraints exist between my servers and an external server that I don't have control over. Is there a linux command/tool that could ...
4
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5answers
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Monitoring Bandwidth Usage (Per Internal IP) - Cisco ASA 5505

I manage a small network with a Cisco ASA 5505 and a shared DSL connection. I would like to be able monitor the bandwidth usage of the various users/devices on my network (by IP). Can I do that ...
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Speed up rsync by running multiple instances at once?

I have to transfer a big directory to another server. My problem is that i cannot use the full bandwidth that would be available, because one concurrent tcp stream does not get as fast. Basically ...
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Intranet speed test

Does anybody know of any internal intranet bandwidth test applications I can install on our internal servers? I would like to test the speed of our WAN links like those online boradband speedometers ...