

Ask HN: Trying to understand a high latency scenario - niels_olson

This is a personal issue, but I'm hoping you guys can share some more general principles:<p>I recently moved to San Diego and it took a while to unpack the router, so we hooked a laptop directly to the cable modem, and, as promised, enjoyed a blazing fast 30 mbps connection. After a few days, I found the router, and plugged it in. The connection suddenly took forever. 20 seconds on average to load a page. Speedtest showed 20 mbps a latency of 1.1 <i>seconds</i>. When I ran mtr, the ping times were consistently between 0.9 and 1.6 <i>seconds</i>.<p>I was using an overclocked WRT54G v 5 (250 MHz) with DDWRT firmware, so I changed to a factory WRT54G v8 (240 MHz), which did no better. I went back to a direct connection, and the problem resolved (latency by mtr: 50-90 ms). I bought an AirPort Extreme last week (1.2 GHz), and ping times are still super slow (about 1 second). Changing DNS servers (internal, Time Warner, Google, Level 3) did nothing.<p>The modem is a Motorola surfboard 5101.<p>I'm not asking for troubleshooting (although Time Warner's folks have proven useless), but I am curious: why would my network latency as measured by mtr skyrocket with a router inserted, regardless of which router it is?
======
Travis
Do you know that these routers work fine on other people's networks?

Did you see different results in router latency when you connected via wired,
vice wireless? (Sorry if you answered it -- your question had a lot of info in
it, and I couldn't see if this was addressed)

~~~
niels_olson
The routers worked fine on Cox in Virginia and Louisiana. Wired and wireless
are essentially the same.

------
ulysses
The first thing that I would check would be the cables. Do you always use the
same cable when plugging the laptop into the cable modem? Because when you're
adding the router in you're also adding a second cable.

~~~
sophacles
Also, if you use the modem with cable and the router wireless, it is
effectively the same thing.

~~~
niels_olson
I have run mtr from wired and wireless clients, no difference.

