I have a home LAN of 5 machines that for internet connection use a linux
box that masqurades the traffic over a 56k modem. (Yes - this is slow,
but free for me). I want to restrict the ammount of bandwidth users have
over the ppp0 interface, as someone doing an ftp download can slow the
link for other users uses (e.g. telnet, web) that have high interaction
Ideally I would like to let each user have 100% bandwidth if it's just
them, then say restrict to 75% capacity when more than one machine is
using the ppp link. This way the ftp transfer continues at a reduced
rate and the telnet session still has more than enough capacity to be
useable. If however the ftp and telnet originate from the same IP
address then no change will be made and the user himself will have to
slow his usage. Also the Linux box runs its own services such as DNS and
sendmail/fetchmail. Some of these can take a low priority like
sendmail, others like DNS cant.
Any ideas on how best to implement this would be most appreciated. I
have been looking at quality of service and traffic shaping but know
very little of these,. The LAN is set up as follows.
Two subnets (192.168.100.x and 192.168.10.x), both ethernet (one 100Mbs
the other 10Mbs)
Linked to a seperate NIC on the linux box (SuSE 6.0 - kernel 2.2.9)
Each PC on the LAN uses this as the default gateway for traffic
The Linux box will forward between these two ethernet interfaces, and
masqurade anything going over the modem, using IPCHAINS.