If people transfer a lot of data on the local network can Internet connection become slow?

Question

At my work there are at least 40 people sharing the same internet connection link over the same switch that is used both to internet access and local traffic of large file.

People here usually use local network to share large files up to 5GB, so the 10/100MBps ethernet network becomes overloaded most part of the day. At the same time, as some people is sharing these files, other people are using internet to do their work, but at random time of the day, internet becomes unavaiable. So, I'm wondering if the high local loads of file sharing on local network would be a reason to the unavailability of internet on specific times of the day....

Could high local traffic affect internet navigation?

Answer 1

This is somewhat related to the answer here: Poweruser: Does WiFi LAN gaming affect the internet of other users?

The main difference is the traffic is TCP/IP for sure in this case, so if you have a switch (ONLY ONE), there should be no problem. If you have multiple switches, then, the bottleneck is formed due to inter-switches traffic, traffic made both for Internet and intranet.

Answer 2

Since its a switched network, high local traffic will negatively affect only those whose individial connections are being saturated. i.e. those actually doing the local transfers

Answer 3

Yes, these can affect the Internet connection. The network between the computers and the internet switch is the same as is used for local traffic in most cases. So if a lot of people are transferring a large volume of files locally this can choke off the traffic to external sites. This can be controlled to an extent by a network admin setting up the network to throttle different types of traffic to allow bandwidth to remain available for http and other external connections.

Answer 4

With no doubt what actually travels through the..."wire" affects activity on the medium itself, moreover when it is used bidirectionally for local and www traffic...

i would recommend reproducing the problem and seeing for yourself by simulating a slow network yourself...one tool that comes to mind is TMNetSim ....

Afterwards you can "dig" even deeper by sniffing traffic and seeing what goes on there...