First thanks all for feedback As usual for me, my haste injects problems. As a new information lead in I specifically suspect the cable company. The cable modem over a period of time of low to no use, that is, when I'm away will be displaying upon my return an indication that it is having a signal strength problem. Connectivity to the outside world from the workstation will have been lost. A modem reset, svi dhclient restart and svi network reload will get the firewall back up. An ipconfig /renew on the workstation and I'm back in business. The cable company will be out Monday morning to check this out.
At 11:39 AM 4/30/2002 -0700, you wrote: >At 12:04 PM 4/30/02 -0500, Dennis Stephens wrote: > >Have started this morning with a cable modem problem and worked through it > >with Tech Support. Now the through put is less than half of what it should > >be. How can I determine that the problem is on the provider's side of the > >system and not in my firewall or home network? > >For our purposes, a good starting place would be describing what you mean by >"through put is less than half of what it should be". What throughput are >you expecting, what are you getting, and how are you measuring it (include >between where and where)? The system in question is a Win 2k workstation behind a Dachstein firewall connected to a cable modem. This provides me email, news and web surfing access. The VPN is client software run on the workstation that is port forwarded to/through the firewall and connects to a VPN server at the company I work for. No real VPN on the firewall except using ip_masq_ipsec. The advertised rate the cable company is supposed to be supporting is 764k down and 128k up. Now that is bits so I need to divide by eight (give or take a bit) that would be ~95.5kb/sec. A sample 5mb file they have at their site comes over at 45kb/sec peak to a low in single digits and sometimes times out. A lot of internet surfing can time out, accessing the email account can time out. I have been able to document speeds on a test file in the past, one and two months ago, that were closer to 900k down and 200k up. >I ask because the traceroute result you report below is not really a local >throughput measure, and response delays of the sort you mention there are >far from surprising. I couldn't repliacte your experience this morning, but >then I'm "closer" to Yahoo (only 10 steps) than you apparently are. > snip, snip... >In practice, with equipment of the quality you are using, I've seen about a >10% hirt on throughput. But only at the higher levels of LAN-to-LAN routing >(nominally 10 Mbps; in practice, about 5 Mbps). The usual range of offsite >connections -- 384 Kbps to 1544 Kbps -- does not normally induce >router-based throughput losses. > > >They are taking the > >position (of course they would), that they can not see a reason for the > >reduction. The Dachstien floppy is working fine, with only a slight hole > >poked through it for my VPN connection to the corporation. > >A 486/66 is plenty fast for a normal NAT'ing router, but it isn't very much >horsepower for running a VPN. From what you wrote, I can't tell where in the >system the VPN'ing is being done. If on the router, that could be slowing >things down. > >When you are having speed problems, what does the router's CPU utilization >look like? (Can someone remind me how to check this in Dachstein? I usually >use top for this, but I don't think Dachstein includes it.) I give, that was the basis of my question(s). How do I document what the firewall is doing other than the packet handling results in system logs. > >Everything is > >working, the weblet, the bandwidth monitor et al. Just working > >slowly. > >Do you really mean that a connection from the Weblet to a host on the LAN is >"working slowly"? If so, this suggests a local problem, not a cable-side >problem. No, that (weblet page) pops up crisp and fast. > >How do I determine where a bottleneck or degradation is > >occurring? Did a traceroute from here to yahoo and had a hop that was 200+ > >ms and one other of the 22 hops that was 700+.ms. > >Where was "here"? The router or a host on the LAN behind the router? Was the >VPN involved? As described above here is where this email was created a workstation behind the Dachstein firewall. >Depending on time of day and other details, delays of this sort can occur >without the cable company (or anything else local) being at fault. > > >Truly appreciate any > >guidance and greatly appreciate the programming and work of all that helped > >with this great application. > > snip... Ditto the last paragraph. This forum always shows up in spades and for that I am grateful. As Always...
