A small ISP at one of our small cities is claiming a fiber cut took them offline.. I can't buy it that it goes from ATlanta to San Fran in 1 hop.... Trace to www.advi.net 10 12.122.12.50 0ms 10ms 10ms TTL: 0 (ggr1-p380.attga.ip.att.net probable bogus rDNS: No DNS) 11 192.205.32.126 10ms 10ms 0ms TTL: 0 (att-gw.sf.uu.net probable bogus rDNS: 12 Request timed out We are moving a mail server and got caught...
-----Original Message----- From: Mike (meuon) Harrison [mailto:meuon@highertech.net] Sent: Monday, April 21, 2003 5:46 PM To: McBurnett, Jim Cc: nanog@merit.edu Subject: Re: Fiber cut?
On Mon, 21 Apr 2003, McBurnett, Jim wrote:
Does anyone know about a supposed fiber cut on the AT&T side
to UU.net in Hotlanta??
We route out of Atlanta on UU.net.. looks good here:
HOST LOSS RCVD SENT BEST AVG shredder-1a.higherbandwidth.net 0% 10 10 0.17 0.23 ru-1.higherbandwidth.net 0% 10 10 0.51 0.57 500.Serial3-11.GW7.ATL1.ALTER.NET 0% 10 10 2.77 3.34 174.at-1-0-0.XL3.ATL1.ALTER.NET 0% 10 10 3.05 3.77 0.so-7-0-0.XL1.ATL5.ALTER.NET 0% 10 10 3.52 6.02 POS6-0.BR2.ATL5.ALTER.NET 0% 10 10 3.37 4.83 204.255.174.150 0% 10 10 4.22 4.97 gbr4-p50.attga.ip.att.net 0% 10 10 4.26 5.38 gbr4-p30.wswdc.ip.att.net 0% 10 10 18.59 20.46 gbr3-p60.wswdc.ip.att.net 0% 10 10 17.83 19.09 gbr3-p80.sl9mo.ip.att.net 0% 10 10 29.09 30.14 gbr1-p10.bgtmo.ip.att.net 0% 10 10 29.56 31.59 12.122.248.254 0% 10 10 30.02 32.23 192.168.254.42 0% 10 10 30.30 31.12 204.127.166.135 0% 10 10 30.11 32.80
On Mon, 21 Apr 2003, McBurnett, Jim wrote:
A small ISP at one of our small cities is claiming a fiber cut took them offline..
This is NANOG, and this is pretty basic, so this is probably the wrong forum for this explanation. That said, if a small ISP gets taken off line by a fiber cut, it's far more likely to be somewhere between the major backbone and the ISP (a circuit which from the ISP's perspective may be controlled by the major backbone), than it is that the fiber cut will actually isolate the major backbone's POP. The major backbones at this point have a fair amount of redundancy built in, while the circuit from the major backbone to the ISP is likely to be a single circuit on a single path. Still, even in that environment, most circuit outages are not fiber cuts.
I can't buy it that it goes from ATlanta to San Fran in 1 hop....
Trace to www.advi.net 10 12.122.12.50 0ms 10ms 10ms TTL: 0 (ggr1-p380.attga.ip.att.net probable bogus rDNS: No DNS) 11 192.205.32.126 10ms 10ms 0ms TTL: 0 (att-gw.sf.uu.net probable bogus rDNS: 12 Request timed out
Not to mention that they'd have to have discovered faster light. ;) -Steve
On Mon, 21 Apr 2003, Steve Gibbard wrote:
I can't buy it that it goes from ATlanta to San Fran in 1 hop....
Trace to www.advi.net 10 12.122.12.50 0ms 10ms 10ms TTL: 0 (ggr1-p380.attga.ip.att.net probable bogus rDNS: No DNS) 11 192.205.32.126 10ms 10ms 0ms TTL: 0 (att-gw.sf.uu.net probable bogus rDNS: 12 Request timed out
Not to mention that they'd have to have discovered faster light. ;)
you didn't get the memo? This is new MCI-Lite! Fast and cooler than the older stoggier (stoogier?) light.
On Mon, 21 Apr 2003, Steve Gibbard wrote:
This is NANOG, and this is pretty basic, so this is probably the wrong forum for this explanation. That said, if a small ISP gets taken off line by a fiber cut, it's far more likely to be somewhere between the major backbone and the ISP (a circuit which from the ISP's perspective may be controlled by the major backbone), than it is that the fiber cut will actually isolate the major backbone's POP. The major backbones at this point have a fair amount of redundancy built in, while the circuit from the major backbone to the ISP is likely to be a single circuit on a single path.
Still, even in that environment, most circuit outages are not fiber cuts.
There are no reliable public statistics concerning outage causes for IP networks. The FCC and NRIC have a focus group establishing a voluntary outage reporting process for Cable, IP and Wireless providers. See http://www.nric.org/ Last quarter 49% of all FCC reported outages were facility failures (cable cuts and similar outside plant problems). Other sources of outages were Signalling (21%), CO Power (12%), Local switch (12%) and Tandem switch (6%).
participants (4)
-
Christopher L. Morrow -
McBurnett, Jim -
Sean Donelan -
Steve Gibbard