Re: Sub-optimal Charter/Spectrum (AS20115) routing from Greater KC Market

[Jim Troutman via NANOG <nanog () lists nanog org>]

I am not a Spectrum customer.

However, as a consultant I have had customers on the Charter Spectrum
network in Maine (legacy Time Warner network). They too can experience
sub-optimal routing, with traffic sometimes going to Chicago before exiting
to the Internet.  I have also seen instances where the routing from Maine
to some of public anycast DNS servers was picking west coast servers.

I have had a number of conversations about these facts and customer
experience issues at a variety of levels of decision makers at Spectrum
over several years.

I hope there will be some eventual changes in their network routing,
resulting from the Cox merger.

In my experience in all ISP/carrier M&A activity, the underlaying physical
networks never really get integrated.  Maybe a few NNIs in key locations,
 but usually they continue to operate as separate islands for years or even
decades post-merger.

The problem is the fact in that in most carriers, the expense and
investment decisions are driven by accountants with spreadsheets, not by
engineering.

The spreadsheet calculates costs,  it doesn't have a column for customer
experience.  Unless there is meaningful local competition for broadband
service, that is a rational business position.

I hope your customer experience will improve.


Jim Troutman,
jamesltroutman () gmail com
Pronouns: he/him/his
207-514-5676 (cell)

On Wed, Oct 28, 2026 at 11:22 Josephina Lacy via NANOG <
nanog () lists nanog org> wrote:

> Hi NANOG,
>
> I am a Charter/Spectrum (AS20115) residential subscriber out of the
> northern Kansas City regional market (specifically Excelsior Springs, MO).
> I am posting to the list because multiple households across different
> cities in our area (including Liberty, MO) are experiencing severe routing
> inefficiencies when targeting Midwest and Southern destinations.
>
> I don't manage BGP topology myself, but looking at our traceroutes, it
> appears that Charter’s internal backbone is consistently hauling
> out-of-region Chicago and Dallas traffic to Denver, Western Nebraska before
> turning it back around. This introduces an unnecessary 30-60ms latency
> penalty.
>
> To illustrate the contrast, a regional competitor in the exact same
> neighborhood (United Fiber, AS14371) successfully routes traffic straight
> from KC to Chicago in 22ms via Arelion, and reaches Dallas in 34ms.
> Meanwhile, Spectrum subscribers are hitting 55ms-75ms minimum for the exact
> same endpoints due to internal multi-state detours.
>
> I have compiled our local telemetry below to help any Charter backbone or
> peering engineers on the list look into why our regional aggregation edge
> is failing to use local path optimizations.
>
>
> ==============
> 1. CHICAGO (ORD) DESTINATIONS: SPECTRUM VS. UNITED FIBER
> ==============
> Packets targeting Chicago from Spectrum route northwest into Nebraska,
> encountering a severe 40-45ms latency step-up entirely within Charter's
> internal transit hops before trailing up through Minnesota to reach
> Illinois.
>
> [Spectrum User 1 - Excelsior Springs, MO]
>  7    24 ms    26 ms    24 ms  lag-100.mcr01sctsnedc.netops.charter.com
>  8    67 ms    69 ms    69 ms  lag-9.mcr11sctsnedc.netops.charter.com
> ...
> 16    56 ms    58 ms    59 ms  162-254-193-71.valve.net
>
> [Spectrum User 2 - Liberty, MO]
>  8    21 ms    19 ms    21 ms  lag-102.mcr01krnynegg.netops.charter.com
>  9    64 ms    63 ms    61 ms  lag-9.crr01gdisne.netops.charter.com
> ...
> 17    56 ms    53 ms    54 ms  162-254-193-71.valve.net
>
> [United Fiber Baseline -  Excelsior Springs, MO]
> United Fiber drops locally into a KC hub (MCI), hands off directly to
> Arelion, and takes a clean line straight east to Chicago in 22ms flat:
>   4    13 ms    11 ms    10 ms  be6661.ccr22.mci01.atlas.cogentco.com
>   5    13 ms    11 ms    11 ms  arelion.mci01.atlas.cogentco.com
>   6    23 ms    22 ms    22 ms  chi-bb2-link.ip.twelve99.net
> ...
>  11    25 ms    24 ms    22 ms  162-254-193-71.valve.net
>
>
> ==============
> 2. DALLAS (DFW) DESTINATIONS: SPECTRUM VS. UNITED FIBER
> ==============
> To reach Dallas (approx. 500 miles directly south of KC), Spectrum routes
> traffic west to Denver, north through Nebraska and Minnesota, east to
> Chicago, and back down south.
>
> [Spectrum User 1 - Excelsior Springs, MO]
>  7    27 ms    25 ms    28 ms  lag-100.mcr01sctsnedc.netops.charter.com
>  8    69 ms    66 ms    66 ms  lag-9.mcr11sctsnedc.netops.charter.com
> ...
> 18    65 ms    62 ms    66 ms  162-254-194-1.valve.net
>
> [Spectrum User 2 - Liberty, MO]
>  7    37 ms    32 ms    34 ms  lag-100.mcr01sctsnedc.netops.charter.com
>  8    66 ms    67 ms    68 ms  lag-9.mcr11sctsnedc.netops.charter.com
> ...
> 18    75 ms    75 ms    69 ms  162-254-194-1.valve.net
>
> [United Fiber Baseline -  Excelsior Springs, MO]
>   4     8 ms     8 ms     8 ms  be6661.ccr22.mci01.atlas.cogentco.com
>   5    14 ms    11 ms    12 ms  be5591.ccr32.oma02.atlas.cogentco.com
>   6    22 ms    20 ms    21 ms  be5068.ccr42.ord01.atlas.cogentco.com
>   7    20 ms    21 ms    20 ms  be2766.ccr41.ord03.atlas.cogentco.com
> ...
>  14    34 ms    34 ms    34 ms  162-254-194-1.valve.net
>
>
> ==============
> FULL SPECTRUM TRACEROUTE FOR REFERENCE
> ==============
> [User 1 - Excelsior Springs, MO to Valve Chicago]
>   1    <1 ms    <1 ms    <1 ms  console.gl-inet.com
>   2     6 ms     8 ms     6 ms  vlan-200.ana05kscymogp.netops.charter.com
>   3    23 ms    19 ms    23 ms  lag-46.hcr11kscymogp.netops.charter.com
>   4     8 ms     6 ms     5 ms  lag-20.hcr02kscymogp.netops.charter.com
>   5    11 ms    10 ms     8 ms  lag-28.mcr01ksczksmp.netops.charter.com
>   6    26 ms    25 ms    24 ms  lag-101.mcr01dnvrco26.netops.charter.com
>   7    24 ms    26 ms    24 ms  lag-100.mcr01sctsnedc.netops.charter.com
>   8    67 ms    69 ms    69 ms  lag-9.mcr11sctsnedc.netops.charter.com
>   9    57 ms    56 ms    56 ms  lag-401.crr02gdisne.netops.charter.com
>  10    57 ms     *        *     lag-808.bbr01stcdmn.netops.charter.com
>  11    54 ms    54 ms    53 ms  lag-1.bbr02chcgil.netops.charter.com
>  12    55 ms    58 ms    57 ms  lag-802.prr01chcgil.netops.charter.com
>  13     *        *        *     Request timed out.
>  14     *        *        *     Request timed out.
>  15    57 ms    53 ms    57 ms  162-254-193-131.valve.net
>  16    56 ms    58 ms    59 ms  162-254-193-71.valve.net
>
> [User 2 - Liberty, MO to Valve Dallas]
>   1     1 ms    <1 ms    <1 ms  SAX1V1S.lan
>   2    13 ms    16 ms    13 ms  syn-070-094-032-001.res.spectrum.com
>   3    31 ms   188 ms    30 ms  lag-58.hcr12kscymogp.netops.charter.com
>   4    18 ms    19 ms    16 ms  lag-21.hcr02kscymogp.netops.charter.com
>   5    13 ms    13 ms    17 ms  lag-28.mcr01ksczksmp.netops.charter.com
>   6    34 ms    35 ms    33 ms  lag-101.mcr01dnvrco26.netops.charter.com
>   7    37 ms    32 ms    34 ms  lag-100.mcr01sctsnedc.netops.charter.com
>   8    66 ms    67 ms    68 ms  lag-9.mcr11sctsnedc.netops.charter.com
>   9    75 ms    72 ms    73 ms  lag-401.crr02gdisne.netops.charter.com
>  10    77 ms     *       70 ms  lag-808.bbr01stcdmn.netops.charter.com
>  11    76 ms    72 ms    76 ms  lag-1.bbr02chcgil.netops.charter.com
>  12    88 ms    80 ms    78 ms  lag-22.bbr01olvemo.netops.charter.com
>  13    79 ms    84 ms    78 ms  lag-3.bbr01blvlil.netops.charter.com
>  14    73 ms    68 ms    71 ms  lag-805.bbr01dllstx.netops.charter.com
>  15    75 ms    70 ms    72 ms  lag-801.prr01dllstx.netops.charter.com
>  16   104 ms    69 ms    73 ms  162-254-194-144.valve.net
>  17     *        *        *     Request timed out
>  18    75 ms    75 ms    69 ms  162-254-194-1.valve.net
>
> ==============
> FULL UNITED FIBER TRACEROUTE FOR REFERENCE
> ==============
> [User 3 - Excelsior Springs, MO to Valve Chicago]
>   1     1 ms     1 ms     1 ms  router.home.local [192.168.1.1]
>   2    26 ms    16 ms    16 ms  38.148.167.1
>   3     7 ms     4 ms     4 ms  10.20.0.29
>   4    13 ms    11 ms    10 ms  be6661.ccr22.mci01.atlas.cogentco.com
> [38.20.20.129]
>   5    13 ms    11 ms    11 ms  arelion.mci01.atlas.cogentco.com
> [154.54.11.46]
>   6    23 ms    22 ms    22 ms  chi-bb2-link.ip.twelve99.net
> [62.115.139.124]
>   7    19 ms     *        *     chi-b24-link.ip.twelve99.net
> [62.115.137.29]
>   8    21 ms    22 ms    22 ms  valve-ic-392833.ip.twelve99-cust.net
> [62.115.202.235]
>   9     *        *        *     Request timed out.
>  10    24 ms    22 ms    22 ms  162-254-193-130.valve.net
> [162.254.193.130]
>  11    25 ms    24 ms    22 ms  162-254-193-71.valve.net [162.254.193.71]
>
> [User 3 - Excelsior Springs, MO to Dallas]
>   1     1 ms     1 ms     1 ms  router.home.local [192.168.1.1]
>   2    11 ms    15 ms    16 ms  38.148.167.1
>   3     6 ms     3 ms     4 ms  10.20.0.29
>   4     8 ms     8 ms     8 ms  be6661.ccr22.mci01.atlas.cogentco.com
> [38.20.20.129]
>   5    14 ms    11 ms    12 ms  be5591.ccr32.oma02.atlas.cogentco.com
> [154.54.89.2]
>   6    22 ms    20 ms    21 ms  be5068.ccr42.ord01.atlas.cogentco.com
> [154.54.166.74]
>   7    20 ms    21 ms    20 ms  be2766.ccr41.ord03.atlas.cogentco.com
> [154.54.46.178]
>   8     *       23 ms    21 ms  ix-bundle-19.qcore1.ct8-chicago.as6453.net
> [66.110.15.38]
>   9    35 ms    34 ms     *
> if-bundle-2-2.qcore2.ct8-chicago.as6453.net
> [66.110.15.37]
>  10     *       34 ms    33 ms
> if-bundle-63-2.qcore1.dl8-dallas.as6453.net
> [66.198.29.35]
>  11     *        *        *     Request timed out.
>  12    34 ms    34 ms    34 ms  64.86.132.235
>  13     *        *        *     Request timed out.
>  14    34 ms    34 ms    34 ms  162-254-194-1.valve.net [162.254.194.1]
>
> *Any help or insight from the Charter network team would be greatly
> appreciated. I apologize for any errors. Feel free to ask any questions!*
>
> *Thank you!*
> *Josephina Lacy*
> _______________________________________________
> NANOG mailing list
>
> https://lists.nanog.org/archives/list/nanog () lists nanog org/message/QGL3XY7EJACCIS2Y725YEFOK44QPLUBY/
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