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Slow connection to my home server

Regular Visitor

Slow connection to my home server

I work/play remotely sometimes from a different location where I have Comcast internet.

 

A. Home - on AT&T 100 fiber

B. Work - Comcast on Performance Internet

 

Generally, using the internet is plenty fast as I would expect.  Except if I need to access files on my home server (large media files and CAD files).

I was seeing slow file transfers from Work to Home.  Super slow.

 

Testing against a server at home, I run `iperf` (I'm on linux in both locations) from a server in NJ to my house to get a general baseline of speeds to that server:

 

root@NJ ~ # iperf3 -p 22 -c HOME
Connecting to HOME, port 22
[  5] local 45.79.131.243 port 38884 connected to xxx.xxx.xxx.xxx port 22
[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec  13.7 MBytes   115 Mbits/sec   39    683 KBytes
[  5]   1.00-2.00   sec  13.8 MBytes   115 Mbits/sec    0    775 KBytes
[  5]   2.00-3.00   sec  13.8 MBytes   115 Mbits/sec    9    591 KBytes
[  5]   3.00-4.00   sec  12.5 MBytes   105 Mbits/sec    0    634 KBytes
[  5]   4.00-5.00   sec  15.0 MBytes   126 Mbits/sec    0    659 KBytes
[  5]   5.00-6.00   sec  13.8 MBytes   115 Mbits/sec    0    673 KBytes
[  5]   6.00-7.00   sec  15.0 MBytes   126 Mbits/sec    0    680 KBytes
[  5]   7.00-8.00   sec  13.8 MBytes   116 Mbits/sec    0    680 KBytes
[  5]   8.00-9.00   sec  13.8 MBytes   115 Mbits/sec    0    680 KBytes
[  5]   9.00-10.00  sec  15.0 MBytes   126 Mbits/sec    0    683 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec   140 MBytes   117 Mbits/sec   48             sender
[  5]   0.00-10.00  sec   137 MBytes   115 Mbits/sec                  receiver

iperf Done.

I'm seeing expected speeds from other servers on the internet back to the HOME network.

So testing from WORK to HOME:

$ iperf -p 22 -c HOME
------------------------------------------------------------
Client connecting to HOME, TCP port 22
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  3] local 192.168.1.23 port 8267 connected with xxx.xxx.xxx.xxx port 22
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.1 sec  7.38 MBytes  6.15 Mbits/sec

To re-iterate - that's giving me 6.15 Mbits/second...  (Performance internet is supposed to be around 60 Mbits/s.

This is roughly the same after a few dozen tests at various times throughout the day.

 

Here's the kicker.  If I create an SSH tunnel from WORK to HOME

$ ssh HOME -L 22:localhost:22

and then re-run the iperf test through the SSH tunnel:

$ iperf -p 22 -c localhost
------------------------------------------------------------
Client connecting to localhost, TCP port 22
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  3] local 127.0.0.1 port 8282 connected with 127.0.0.1 port 22
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec   163 MBytes   137 Mbits/sec

Just to clarify, connecting from WORK to HOME through an SSH tunnel lets me see 137 Mbits/s of transfer - awesome!

 

Connecting from WORK to HOME across the internet shows me 6.15 Mbits/s.

 

The raw speed is obviously there without a problem as evidenced by the speeds through an SSH tunnel.

 

So what is going on here?  Why would my speeds be so poor in this one specific instance to this particular server?

@ComcastJohnN or @ComcastChe ?

 

Regular Contributor

Re: Slow connection to my home server

run iperf Work to Home test without tunneling using a different port other than port 22 because sshd listens on that port as well.

I think this is affecting the reading you get when hitting port 22 with your Work to Home test (that is without tunneling) because sshd thinks it is being  attacked and is limiting badwidth?

Am not sure.

But change the port with that Non tunneling test you do to a non port 22 one for starters.

Regular Visitor

Re: Slow connection to my home server

I've got my ssh running on a different port for these tests.

There is nothing listening on port 22 other than the iperf server.

 

To test, I re-did everything using port 80, and I'm still seeing a measly 6.5 Mbit/sec transfer (no ssh tunnel)...

Regular Visitor

Re: Slow connection to my home server

Just tested again to see if it might be dependent on day.

Nope.  Still awful.

NJ = Server in NJ

WORK = Comcast performance internet from my off-site location

WORK2 = Separate network (ATT) elsewhere in my city

These are all testing speeds back to my home (ATT Fiber) server:

 

-----------------------------------------------------------
Server listening on 22
-----------------------------------------------------------
Accepted connection from NJ, port 59702
[  5] local 10.0.0.2 port 22 connected to NJ port 59704
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.00   sec  9.85 MBytes  82.6 Mbits/sec
[  5]   1.00-2.00   sec  14.6 MBytes   122 Mbits/sec
[  5]   2.00-3.00   sec  14.5 MBytes   121 Mbits/sec
[  5]   3.00-4.00   sec  13.8 MBytes   116 Mbits/sec
[  5]   4.00-5.00   sec  14.2 MBytes   119 Mbits/sec
[  5]   5.00-6.00   sec  14.5 MBytes   122 Mbits/sec
[  5]   6.00-7.00   sec  14.8 MBytes   124 Mbits/sec
[  5]   7.00-8.00   sec  14.8 MBytes   124 Mbits/sec
[  5]   8.00-9.00   sec  14.3 MBytes   120 Mbits/sec
[  5]   9.00-10.00  sec  13.1 MBytes   110 Mbits/sec
[  5]  10.00-10.04  sec   584 KBytes   120 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.04  sec  0.00 Bytes  0.00 bits/sec                  sender
[  5]   0.00-10.04  sec   139 MBytes   116 Mbits/sec                  receiver
-----------------------------------------------------------
Server listening on 22
-----------------------------------------------------------
Accepted connection from WORK, port 50708
iperf3: the client has unexpectedly closed the connection
-----------------------------------------------------------
Server listening on 22
-----------------------------------------------------------
Accepted connection from WORK, port 50712
[  5] local 10.0.0.2 port 22 connected to WORK port 50714
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.00   sec   597 KBytes  4.89 Mbits/sec
[  5]   1.00-2.00   sec   728 KBytes  5.96 Mbits/sec
[  5]   2.00-3.00   sec   727 KBytes  5.95 Mbits/sec
[  5]   3.00-4.00   sec   727 KBytes  5.95 Mbits/sec
[  5]   4.00-5.00   sec   730 KBytes  5.98 Mbits/sec
[  5]   5.00-6.00   sec   725 KBytes  5.94 Mbits/sec
[  5]   6.00-7.00   sec   452 KBytes  3.71 Mbits/sec
[  5]   7.00-8.00   sec  1004 KBytes  8.23 Mbits/sec
[  5]   8.00-9.00   sec   727 KBytes  5.96 Mbits/sec
[  5]   9.00-10.00  sec   730 KBytes  5.98 Mbits/sec
[  5]  10.00-10.08  sec  60.8 KBytes  6.00 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.08  sec  0.00 Bytes  0.00 bits/sec                  sender
[  5]   0.00-10.08  sec  7.04 MBytes  5.86 Mbits/sec                  receiver
-----------------------------------------------------------
Server listening on 22
-----------------------------------------------------------
Accepted connection from WORK2, port 13024
[  5] local 10.0.0.2 port 22 connected to WORK2 port 13025
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.00   sec  7.83 MBytes  65.7 Mbits/sec
[  5]   1.00-2.00   sec  5.18 MBytes  43.4 Mbits/sec
[  5]   2.00-3.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   3.00-4.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   4.00-5.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   5.00-6.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   6.00-7.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   7.00-8.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   8.00-9.00   sec  14.9 MBytes   125 Mbits/sec
[  5]   9.00-10.00  sec  14.9 MBytes   125 Mbits/sec
[  5]  10.00-10.10  sec  1.45 MBytes   125 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.10  sec  0.00 Bytes  0.00 bits/sec                  sender
[  5]   0.00-10.10  sec   134 MBytes   111 Mbits/sec                  receiver

 

 

Something is happening on the Comcast side that is severly effecting my speeds to my server (again, on an AT&T fiber connection) at home.

Is this known?  Is there something Comcast is doing to throttle this speed so much when it's fine from other locations, and even worse, just fine when tested through an encrypted SSH tunnel?

 

@ComcastJohnN or @ComcastChe do you have any insight to add here?