Typical additional latency for CGN?

Jon Lewis jlewis at lewis.org
Mon Oct 8 01:22:54 UTC 2012

On Sun, 7 Oct 2012, Owen DeLong wrote:

>> Most mobile providers have been doing what is commonly called cgn for 5 to
>> 10 years. CGN is not a new concept or implementation for mobile.
> True, but, as we have discussed before, mobile users, especially in the US,
> have dramatically lowered expectations of internet access from their mobile
> devices vs. what they expect from a household ISP.

Speaking of which, has anyone else noticed AT&T mobile is blocking ssh 
(outgoing 22/tcp) connections?  AFAIK, AT&T mobile does CGN.  It's 
puzzling that they'd block outgoing ssh when there have been multiple ssh 
clients in the Apple app store for years.  I used to be able to ssh from 
my AT&T phone.  I found recently, the packets don't get to the server 
unless I VPN from the phone first (or am on wifi, not relying on AT&T for 

  Jon Lewis, MCP :)           |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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