I am having this problem now for too long. I have a stand-alone server running Debian with 2.4 kernel acting as a router/firewall/web/ftp/samba/print-server. The problem consists of really slow in- and out-going speeds. My external NIC is a 100Mbit 3com card ( vortex/boomerang driver ) and the internal NIC is a 100Mbit Netgear FA311. My ISP connection is 10Mbit full duplex BBB connection and my internal connection speed is a 100Mbit full duplex switched network consisting of 3 win2k clients. The fastest total speed from an external source is 1378.0 K/s and my fastest internal speed from and to the linux-server is around 60Kbps. The speed have been around 13000Kbps but now it is as low as DSL-speed. What shall I do or what is wrong?

ifconfig reports no errors on either eth0:

eth0 Link encap:Ethernet HWaddr 00:50:04:48:00:16
inet addr:213.xxx.xxx.xxx Bcast:213.115.122.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:402836369 errors:0 dropped:0 overruns:0 frame:0
TX packets:587228770 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:1194057446 (1.1 GiB) TX bytes:3342660577 (3.1 GiB)
Interrupt:11 Base address:0xdc00

nor on eth1:
eth1 Link encap:Ethernet HWaddr 00:09:5B:09:8E:16
inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:44626955 errors:0 dropped:0 overruns:0 frame:0
TX packets:57661677 errors:13 dropped:0 overruns:13 carrier:13
collisions:0 txqueuelen:100
RX bytes:2730600016 (2.5 GiB) TX bytes:856273384 (816.6 MiB)
Interrupt:5 Base address:0x7000

It would be very helpful if anyone would have a clue on what is going on? Sometimes the speed is good, but now it has been more and more worse and now it is absolutley unacceptable.