March 2017 - Test - lists.nanog.org

Consumer networking head scratcher
by Ryan Pugatch 02 Mar '17

02 Mar '17

Hi everyone, I've got a real head scratcher that I have come across after replacing the router on my home network. I thought I'd share because it is a fascinating issue to me. At random times, my Windows machines (Win 7 and Win 10, attached to the network via WiFi, 5GHz) lose connectivity to the Internet. They can continue to access internal resources, such as the router's admin interface. Other devices including Macs, iPhones, Android phones, and Rokus never have this issue. I realized that on the Windows machines, when the connection drops, if I run a traceroute, it dies at a certain hop every time (out in Comcast's network, who is my ISP) even though a Mac sitting right next to it is able to go all the way through to the destination. The even stranger thing I discovered last night is that if I trace to the hop before the hop that it dies at, it then dies at the hop before that (and as I trace to closer and closer hops, it dies the hop before that!) This is illustrated in the traces I've captured here: http://pastebin.com/raw/R1UHLi0U For what it's worth, the router is a Linksys EA7300 that I just picked up. I can't even imagine what would cause this issue at this point. If anyone has any thoughts, I'd love to hear them! I'm going to start studying some packet captures to see if I can spot an issue. Best, Ryan

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Re: Consumer networking head scratcher
by Ryan Pugatch 02 Mar '17

02 Mar '17

On Wed, Mar 1, 2017, at 06:35 PM, Jean-Francois Mezei wrote: > On 2017-03-01 11:28, Ryan Pugatch wrote: > > > At random times, my Windows machines (Win 7 and Win 10, attached to the > > network via WiFi, 5GHz) lose connectivity to the Internet. > > > For what it's worth, the router is a Linksys EA7300 that I just picked > > up. > > > Way back when, I have a netgear router. It ended having a limit on its > NAT translation table, and when I had too many connections going at same > time (or not yet timed out), I would lose connection. There was an > unofficial patch to the firmware (litterally a patch in code that > defined table size) to increase that table to 1000- as I recall. > > Does the Linksys have a means to display the NAT translation table and > see if maybe connections are lost when that table is full and lots of > connections have not yet timed out ? > It doesn't seem to provide visibility into the NAT tables. However, I'm starting to think you might be on to something. The issue actually happened to my Mac tonight, and sure enough the traceroute dies at the same time. So, it isn't just the Windows machines impacted. I did a packet capture on my end, and on a server somewhere that I control and sent pings from my laptop to the server. The server received my ICMP packets and responded, but those responses never made it back to my laptop. Meanwhile, my Roku is actively streaming from the Internet, so it's not like the Internet was down.

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Re: Consumer networking head scratcher
by Ryan Pugatch 01 Mar '17

01 Mar '17

On Wed, Mar 1, 2017, at 03:58 PM, iamzam(a)gmail.com wrote: > On many non-windows OS (Mac OSX, Linux, FreeBSD etc.) you can specify > ICMP > traceroute using -I: > > traceroute -I google.com > > I wonder if this would replicate your experience with Windows tracert Definitely on my list to test. Thanks.

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IRR database for local usage
by Nagarjun Govindraj 01 Mar '17

01 Mar '17

Hi nanog, Is it possible to maintian an IRR database locally for quering route objects from various RIR's and do a regular sync like what RPKI validator does for ROA's. - Nagarjun

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Research project and survey: Network filtering and IP spoofing
by Franziska Lichtblau 01 Mar '17

01 Mar '17

Hi, we are a team of researchers from TU Berlin [1] working on a measurement project to assess the ramifications of traffic with spoofed source IP addresses in the Internet. To better understand the operational challenges that you as network operators face when deploying (or not deploying) source IP address filtering techniques, we'd like to invite you to participate in our survey. If you could spare 5 minutes of your time, we'd be delighted if you could fill out our survey form and tell us about your current practices regarding network filtering. To participate, please visit: [2] http://filteringsurvey.inet.tu-berlin.de/ If you have any concerns or questions, you can reply on-list or contact us via [3] filtering-survey(a)inet.tu-berlin.de. We will only publish anonymized results of this study and once we've analyzed your feedback we'll publish a digest of the results on-list if you're interested. As you are probably subscribed to more network operator lists you might encounter this mail multiple times. We apologize for cross-posting, but in order to get results that will give us meaningful insights we need the widest coverage we can get. Thank you very much for your support! Franziska Lichtblau [1] www.inet.tu-berlin.de [2] http://filteringsurvey.inet.tu-berlin.de/ [3] filtering-survey(a)inet.tu-berlin.de -- Franziska Lichtblau, M.A. building MAR, 4th floor, room 4.004 Fachgebiet INET - Sekr. MAR 4-4 phone: +49 30 314 757 33 Technische Universität Berlin gpg-fp: 4FA0 F1BC 8B9A 7F64 797C Marchstrasse 23 - 10587 Berlin 221C C6C6 2786 91EC 5CD5

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