heimir
@comcast.net
|  [Connectivity] Backbone packet loss in New England
Hi all,
I've been having serious problems for months now with a VPN connection from my home (Comcast HSI) to my office (Sprint T1). Up until now We've been focused on the Cisco software on my end, my home network etc. and never found anything wrong. Until this weekend when I began to focus on the actual route taken on the backbone. My measurements are:
Target Name: mail.cadec.com
IP: 65.162.255.10
Date/Time: 12/9/2007 13:28:05 to 12/9/2007 13:29:44
Hop Sent Err PL% Min Max Avg Host Name / [IP]
1 100 0 0.0 9 95 15 [73.165.234.1]
2 100 3 3.0 7 32 11 ge-3-40-ur01.portsmouth.nh.boston.comcast.net [68.87.150.57]
3 100 3 3.0 8 36 12 te-5-3-ur02.exeter.nh.boston.comcast.net [68.87.145.101]
4 100 2 2.0 9 57 13 po-22-ur01.newburyport.ma.boston.comcast.net [68.87.145.13]
5 100 1 1.0 10 32 13 po-23-ur01.groveland.ma.boston.comcast.net [68.87.144.129]
6 100 5 5.0 9 89 13 po-24-ur02.lawrence.ma.boston.comcast.net [68.87.144.133]
7 100 3 3.0 10 100 15 po-22-ar01.woburn.ma.boston.comcast.net [68.87.144.137]
8 100 4 4.0 10 84 16 pos-0-1-0-0-cr01.boston.ma.ibone.comcast.net [68.86.85.18]
9 100 24 24.0 17 41 21 COMCAST-IP.edge1.NewYork2.Level3.net [4.78.169.50]
10 99 12 12.1 17 72 22 xe-10-2-0.edge1.NewYork2.Level3.net [4.78.169.49]
11 100 13 13.0 17 159 28 ae-13-69.car3.NewYork1.Level3.net [4.68.16.5]
12 100 12 12.0 17 140 28 sprint-level3-te.NewYork1.Level3.net [4.68.111.158]
13 100 11 11.0 18 87 22 sl-bb23-nyc-6-0.sprintlink.net [144.232.13.14]
14 100 26 26.0 17 106 25 sl-gw17-nyc-0-0.sprintlink.net [144.232.13.236]
15 100 11 11.0 27 51 32 sl-cadec-150872-0.sprintlink.net [144.223.36.206]
16 100 0 0.0 27 54 32 mail.cadec.com [65.162.255.10]
My main concern is with hop-9 having never less than 20% packet loss and sometimes up in 40-60%, depending on the time of day. This packet loss simply means that my home-VPN connection is useless.
I've taken my laptop to downtown Net Cafes where my VPN is working great, without a single config change. Same kind of measurements from there show losses between zero and 5%, typically 1% or less over the whole path!
I've tried to call Comcast support, where the tech did not even understand the problem and began asking his regular scripted questions about my home network!!
Any suggestions? Any chance that Comcast will address this at all? Should I change providers as fast as I can?
/Thanks |
|
Rick
Premium,MVM
join:2001-02-06
Waterbury, CT
clubs:  | if i'm reading your post right.hop 9 is level 3. (a backbone provider).
Comcast doesn't control what happens at that hop.
--
The Coyote captured the RR! Roadrunner Rick is now Comcastic! |
|
EG
The wings of love
Premium
join:2006-11-18
Union, NJ
3 edits | reply to heimir
There is no packet loss indicated at the destination so this may not be true packet loss, but rather be the effects of packet prioritization.
»Tools FAQ »Why am I seeing so much packet loss in my provider's network?
What type of packets is that trace utility using ?
This is not to say that you are not having connectivity issues of some sort.
--
Happy Holidays ! |
|
espaeth
Digital Plumber
Premium,MVM
join:2001-04-21
Minneapolis, MN
 ·voip.ms
·Vitelity VOIP
·Callcentric
·VoiceStick
·ViaTalk
 ·Comcast
 ·Embarq
| reply to heimir
said by heimir :
Any suggestions? Any chance that Comcast will address this at all? Should I change providers as fast as I can? As EG  stated, you can't really rely on intermediate routers to return responses all the time. What do you see if you just run a ping against mail.cadec.com?
ping mail.cadec.com -n 100
If that returns 0% loss, then there is no problem.
-Eric |
|
EG
The wings of love
Premium
join:2006-11-18
Union, NJ
3 edits | Thanks for expanding on this Eric.
Indeed that is the next step 
Whatever it's worth, I show zero packet loss to the C.M.T.S. that you are connected to, and to your office connection:
Ping statistics for 73.165.234.1:
Packets: Sent = 100, Received = 100, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 24ms, Maximum = 37ms, Average = 26ms
Ping statistics for 65.162.255.10:
Packets: Sent = 100, Received = 100, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 20ms, Maximum = 108ms, Average = 24ms
--
Happy Holidays ! |
|
joeblow
join:2007-07-14
Knoxville, TN | reply to heimir
Heh
My lastest roud with the techs they told me I need more ram to fix my packet loss problem. 2 gigs was god enough but now who knows maybe Santa can help me.
Good luck! |
|
espaeth
Digital Plumber
Premium,MVM
join:2001-04-21
Minneapolis, MN
·voip.ms
·Vitelity VOIP
·Callcentric
·VoiceStick
·ViaTalk
·Comcast
·Embarq
| said by joeblow :My lastest roud with the techs they told me I need more ram to fix my packet loss problem. The door is dented, of course the car won't start! |
|
heimir
@cadec.com
| reply to heimir
The root problem I've had on this connection has been serious packet loss over VPN from my home to the office. The VPN is a Cisco client using UDP talking to a Cisco ASM firewall on the other end.
I can ping the firewall with little or no loss, but seeing up to 40-70% packet loss on the VPN going over the same path, of course making the VPN totally useless. So when I saw these internal network loss numbers, I thought I had it figured out!
A dump of the traffic on the firewall at work shows all icmp requests paired with a icmp reply, so it does not seem like a problem on the company network.
Any ideas on what can be going on here?
/Thanks |
|
