My setup:
I have a PC with a Gigabyte GA-MA78S2H motherboard (Realtek Gigabit wired Ethernet on-board). I have the latest drivers (at least the latest driver for the NIC.
I'm connecting via an Edimax BR-6216Mg (again, wired connection).
For some reason I experience short periodic disconnects and reconnects. Specifically, Skype disconnects, tries to connect, succeeds after a short while; incoming SFTP sessions get dropped; using a browser, I sometime get stuck in the DNS lookup or connection to the website and a page won't load. A couple of seconds later, a reload works.
All this happens with Windows XP SP3. With Windows 7, it also happens. (When I initially wrote this question I didn't notice it.)
ipconfig for my adapter:
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
Physical Address. . . . . . . . . : 00-1D-7D-E9-72-9E
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.0.2
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.0.254
DHCP Server . . . . . . . . . . . : 192.168.0.254
DNS Servers . . . . . . . . . . . : 192.117.235.235
62.219.186.7
Lease Obtained. . . . . . . . . . : Saturday, March 10, 2012 8:28:20 AM
Lease Expires . . . . . . . . . . : Friday, January 26, 1906 2:00:04 AM
A result of some tests a couple of the disconnects:
C:\Documents and Settings\eyalroz.BAKNUNIN>nslookup google.com
DNS request timed out.
timeout was 2 seconds.
*** Can't find server name for address 192.117.235.235: Timed out
DNS request timed out.
timeout was 2 seconds.
*** Can't find server name for address 62.219.186.7: Timed out
*** Default servers are not available
Server: UnKnown
Address: 192.117.235.235
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
*** Request to UnKnown timed-out
C:\Documents and Settings\eyalroz.BAKNUNIN>ping 194.90.1.5
Pinging 194.90.1.5 with 32 bytes of data:
Control-C
^C
C:\Documents and Settings\eyalroz.BAKNUNIN>tracert -d 194.90.1.5
Tracing route to 194.90.1.5 over a maximum of 30 hops
1 <1 ms <1 ms <1 ms 192.168.0.254
2 * * 11 ms 10.168.128.1
3 14 ms 13 ms 14 ms 212.179.160.142
4 * * * Request timed out.
5 * * * Request timed out.
6 * * 47 ms 62.219.189.169
7 31 ms 27 ms 32 ms 62.219.189.150
8 15 ms 14 ms 16 ms 192.114.65.202
9 15 ms 15 ms 11 ms 212.143.10.66
10 13 ms 29 ms 31 ms 212.143.12.234
11 35 ms 15 ms 18 ms 212.143.8.72
12 22 ms 22 ms 16 ms 194.90.1.5
I usually ping 194.90.1.5 (which is not at my ISP) with 15ms response time and no losses.
Things I've done/tried:
[2012-03-26] I replaced the cable; I thought that made a difference, but the disconnects were back a while later, so that wasn't it.
Updated the NIC driver.
Tried reducing the MTU (used a utility called Dr. TCP); there was no effect.
I updated my board BIOS revision (which caused all the HW to be
"reinstalled" or re-identified - successfully).
I installed another NIC, and tried switching to it - same effect with the on-board NIC.
A while back I tried another router (although it was an Edimax model) - same problem.
Connected the computer directly, with no router. Same problem.
ping -t to the router (192.168.0.254) gives pongs, nothing is lost, and time
is < 1 ms almost always (sometimes it says 1 or 2 ms). This is the case also during the disconnects.
