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CoxAbuse

join:2003-04-21
Atlanta, GA
reply to deafcon22

Re: [ALL] Youtube streaming fixed by switching to non-Cox DNS se

Based on the symptoms, I assumed YouTube would answer DNS queries with different ip addresses based on the location of the request. That would explain why changing DNS servers would make a difference. What I see instead is that all DNS queries get the same set of responses, no matter where they come from. Instead, YouTube announces those ip blocks from different locations. So a traceroute to 208.65.153.253 leads to a west coast data center for west coast customers, and it leads to an east coast data center (looks like Miami, FL) for east coast customers.

deafcon22, can you confirm by posting up nslookup and tracert information from your PC? First, change your DNS server back to Cox. Then go to Start -> Run, type in "cmd", and hit enter. When the DOS window appears, type these commands:

nslookup www.youtube.com

nslookup www.youtube.com 208.67.222.222

The output will look like what tubbynet pasted, e.g.

Non-authoritative answer:
Name: www.youtube.com
Address: 208.67.216.132

After you have the replies, please trace the route to each like so:

tracert -d ip address

E.g.

tracert -d 208.67.216.132

It looks like this from Atlanta:

Tracing route to youtube.l.google.com [208.117.236.74]
over a maximum of 30 hops:

...
6 2 ms 2 ms 2 ms 68.1.0.4
7 2 ms 2 ms 2 ms 68.1.0.29
8 3 ms 3 ms 3 ms 154.54.5.113
9 211 ms 58 ms 265 ms 154.54.5.38
10 117 ms 17 ms 206 ms 154.54.7.145
11 17 ms 17 ms 18 ms 154.54.24.234
12 31 ms 31 ms 31 ms 38.104.94.18
13 * * * Request timed out.
14 * * * Request timed out.
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 79 ms 79 ms 79 ms 208.117.236.74

68.1.0.29 is the last Cox router in the trace. We hand off to Cogent at 154.54.5.113, and that link looks great. Latency increases once the packets get into the Cogent network.
--
The Cox Abuse Team


JBT

join:2002-12-06
Tucson, AZ

Its been slow for me on both Cox and opendns DNs servers. It seems to come and go. Fast one hour slow the next.


Graycode

join:2006-04-17
reply to CoxAbuse

Click for full size
Click for full size
said by CoxAbuse:

Based on the symptoms, I assumed YouTube would answer DNS queries with different ip addresses based on the location of the request. That would explain why changing DNS servers would make a difference. What I see instead is that all DNS queries get the same set of responses, no matter where they come from. Instead, YouTube announces those ip blocks from different locations.
I think the problem is caused by the YouTube DNS TTL settings, not by the IP answered by their DNS.

It hurts that YouTube specifies a short 5 minute TTL. As Cox and other DNS servers dispense the popular site from their DNS cache, their remaining TTL just doesn't last very long before another DNS re-query is needed. Too bad also they have the same TTL on the CNAME for youtube.l.google.com.

If you were lucky to request DNS after it had expired in cache, you'd get the full 300 seconds. Generally you'll probably get an average of 2 1/2 minutes worth of remaining TTL, then pause while DNS is queried again.

The link below shows a raw DNS lookup through the root servers. It shows the 300 second (max) TTL. The result is shown in the 1st attached image.
»www.dollardns.net/cgi-bin/dnscra···y#report

The next link shows a query through one of the Cox DNS servers. Use your browser's Reload button to watch the remaining TTL values decrease, that's what would be reported to your PC. This is shown by the 2nd attached image.
»www.dollardns.net/cgi-bin/dnscra···y#report

Or if you'd rather query 4.2.2.1, you'll see the same thing. This isn't Cox's problem.
»www.dollardns.net/cgi-bin/dnscra···y#report

The problem seems to lie with YouTube / Google DNS. Cox and other DNS is functioning properly by caching and re-querying YouTube DNS as needed when TTL expires. A site like YouTube should have much longer DNS TTL because it takes a while to watch a video.


Some Guy

@64.15.114.x

You folks are so focused on one thing... dns to www.youtube.com. If you bothered to look at the entire user session, you would notice that viewing a video doesn't come from www.youtube.com, it fetches from specific hosts not mentioned in this thread at all.... for me the place the actual bulk file (video stream) comes from is:

»v18.cache.googlevideo.com

I've also seen it say things like "nyc-v105.nyc.youtube.com"... and 5 other subdomains... and hundreds of other host-names.

How about you dig into your session and post some useful data about where your buffering bad stream is coming from? use tools like wget, curl, tcpdump... look for actual thruput... tcp retransmits... ping the hosts for packetloss... etc... find some common denominators... east coast, west coast only a certain range of hosts/ip's (on the google/youtube end) etc...

Dwelling on the TTL time of DNS for the first packet of the complicated session is misguided effort.

As an aside, I've noticed a huge icmp ttl range for possible video sources implying many many locations (colo's, cities, countries, etc)... but all the ip's that resolve from www.youtube.com are the same icmp ttl... implying one location where the web front end lives.

,Some Guy


ependergrass

join:2007-07-21
Broken Arrow, OK

2 edits
reply to deafcon22



Blazing speeds again as usual. Hey, I think I even edged out 128kbps ISDN! Time to find a new video site I guess.



KrK
Heavy Artillery For The Little Guy
Premium
join:2000-01-17
Tulsa, OK
reply to deafcon22

Actually I think it is a Cox issue. The second I switched from DSL to Cox my problems with streaming video began... at Youtube and other sites.

It's so bad that even the ads fail a lot... (Very unusual-- normally the ads stream fine and the video you WANT to watch stalls so you have to reload and watch the ads again--- infuriating...) at least with Cox even the ads die.
--
"Fascism should more properly be called corporatism because it is the merger of state and corporate power." -- Benito Mussolini



KrK
Heavy Artillery For The Little Guy
Premium
join:2000-01-17
Tulsa, OK
reply to tubbynet

said by tubbynet:

it is not a cox problem, it is a cache/peer issue between cox and google,
Explain how that makes it not Cox's problem, however.
--
"Fascism should more properly be called corporatism because it is the merger of state and corporate power." -- Benito Mussolini


charterengr
Premium,VIP
join:2002-03-09
Englewood, CO

1 recommendation

reply to deafcon22

Cox Engineers and Google Engineers are in contact. We're working this......



BillRoland
Premium
join:2001-01-21
Ocala, FL
kudos:3
Reviews:
·Cox HSI

said by charterengr:

Cox Engineers and Google Engineers are in contact. We're working this......
That's very good news, thanks charterengr See Profile
--
"Don't steal. The government hates competition."

James887

join:2008-07-12
reply to charterengr

Been getting worst the past 2 weeks here in the New England Market, havent saw it relaly before, just the past 2 weeks. Hopefully it is resolved soon, been having multiple ppl complain about it in RI and CT.



Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3

1 edit
reply to CoxAbuse

said by CoxAbuse:

Based on the symptoms, I assumed YouTube would answer DNS queries with different ip addresses based on the location of the request. That would explain why changing DNS servers would make a difference. What I see instead is that all DNS queries get the same set of responses, no matter where they come from. Instead, YouTube announces those ip blocks from different locations. So a traceroute to 208.65.153.253 leads to a west coast data center for west coast customers, and it leads to an east coast data center (looks like Miami, FL) for east coast customers.

deafcon22, can you confirm by posting up nslookup and tracert information from your PC? First, change your DNS server back to Cox. Then go to Start -> Run, type in "cmd", and hit enter. When the DOS window appears, type these commands:

nslookup www.youtube.com

nslookup www.youtube.com 208.67.222.222

The output will look like what tubbynet pasted, e.g.

Non-authoritative answer:
Name: www.youtube.com
Address: 208.67.216.132

After you have the replies, please trace the route to each like so:

tracert -d ip address

E.g.

tracert -d 208.67.216.132

It looks like this from Atlanta:

Tracing route to youtube.l.google.com [208.117.236.74]
over a maximum of 30 hops:

...
6 2 ms 2 ms 2 ms 68.1.0.4
7 2 ms 2 ms 2 ms 68.1.0.29
8 3 ms 3 ms 3 ms 154.54.5.113
9 211 ms 58 ms 265 ms 154.54.5.38
10 117 ms 17 ms 206 ms 154.54.7.145
11 17 ms 17 ms 18 ms 154.54.24.234
12 31 ms 31 ms 31 ms 38.104.94.18
13 * * * Request timed out.
14 * * * Request timed out.
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 79 ms 79 ms 79 ms 208.117.236.74

68.1.0.29 is the last Cox router in the trace. We hand off to Cogent at 154.54.5.113, and that link looks great. Latency increases once the packets get into the Cogent network.
This is what I recieved following your directions.
These results where rendered using OpenDNS.

C:\>nslookup www.youtube.com
Server: DD-WRT
Address: 192.168.1.1

Non-authoritative answer:
Name: youtube.l.google.com
Address: 208.117.236.71
Aliases: www.youtube.com

C:\>tracert -d 208.117.236.71

Tracing route to 208.117.236.71 over a maximum of 30 hops

1 2 ms 1 ms 1 ms 192.168.1.1
2 11 ms 10 ms 12 ms 70.189.23.1
3 13 ms 9 ms 11 ms 24.249.37.137
4 9 ms 9 ms 18 ms 24.249.36.145
5 12 ms 11 ms 10 ms 24.249.36.193
6 31 ms 34 ms 23 ms 68.1.1.234
7 111 ms 198 ms 201 ms 38.101.173.114
8 * * * Request timed out.
9 * * * Request timed out.
10 * * * Request timed out.
11 * * * Request timed out.
12 67 ms 72 ms 65 ms 208.117.236.71

Trace complete.

C:\>


cob_
1310nm Of Goodness
Premium
join:2003-07-08
Tulsa, OK
reply to charterengr

said by charterengr:

Cox Engineers and Google Engineers are in contact. We're working this......
That's why Cox is the best ISP in this area, right thar...


DataRiker
Premium
join:2002-05-19
00000
reply to deafcon22

I just saw this, and I thought i was the only one who noticed this issue.

I can no longer use youtube because of the extreme annoying delays every 2 seconds.



Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3

Change your dns and it will fix the issue, it did for me.


jeff9329
Premium
join:2002-04-16
Virginia Beach, VA
reply to deafcon22

On my VA Beach Cox connection, Utube has been totally unusable for quite a while.



CoxAbuse

join:2003-04-21
Atlanta, GA
reply to deafcon22

Give it a try now and let us know if you see a difference.
--
The Cox Abuse Team


James887

join:2008-07-12
reply to deafcon22

Working a lot better now here in RI, buffering is fixed. Tried several videos that I never watched before.



BillRoland
Premium
join:2001-01-21
Ocala, FL
kudos:3
Reviews:
·Cox HSI
reply to CoxAbuse

said by CoxAbuse:

Give it a try now and let us know if you see a difference.
No difference, still very slow.
--
"Don't steal. The government hates competition."


Mike00
Premium
join:2002-09-16
Tulsa, OK
reply to deafcon22

How do I find out which dns I should change to?



dvd536
as Mr. Pink as they come
Premium
join:2001-04-27
Phoenix, AZ
kudos:4

said by Mike00:

How do I find out which dns I should change to?
4.2.2.1
4.2.2.2
--
When I gez aju zavateh na nalechoo more new yonooz tonigh molinigh - Ken Lee


Fubar16

join:2001-02-20
Phoenix, AZ
kudos:2
reply to deafcon22

Problem has been fixed:

»Re: [CT] YouTube videos load SLOWLY, everything else FAST!

And why is this thread open if this one is closed ( »[CT] YouTube videos load SLOWLY, everything else FAST! )?



Dogfather
Premium
join:2007-12-26
Laguna Hills, CA
reply to Ikyuao

I read that about 5 times and still can't figure out WTF you're talking about.



stanley_qaz
Premium
join:2003-03-17
Gilbert, AZ
Reviews:
·Cox HSI
·HughesNet Satell..
reply to Fubar16

said by Fubar16:

Problem has been fixed:
It seems to be fixed some of the time but once in a while over the last day I've still been getting long pauses in YouTube downloads. It usually clears in a few minutes and I'm using OpenDNS so I figured to give it another 24 hours before I complained.


Plasticman
Will Work For Bandwidth
Premium
join:2002-09-06
Johnston, RI

The only time I have had issues with youtube is at night. I see slow load times and buffering on videos. But in the morning I have no problems.....



Click on my egg and visit it.... It's lonely...
--
Grant me the serenity to accept the things I cannot change, the courage to change the things I cannot accept, and the wisdom to hide the bodies of those people I had to kill today because they pissed me off


Pist

join:2007-12-30
Broken Arrow, OK
reply to deafcon22

It seems to mess up for me too, takes forever for videos to buffer in the afternoon and night.