strange behaviour of firefox

Chris Adams cmadams at hiwaay.net
Fri Aug 12 01:05:36 UTC 2011


Once upon a time, Rick Stevens <ricks at nerd.com> said:
> There is a reason for this, Joel.  Most ISPs that deal with home users
> use a loop polling mechanism to pick up data from end users and ship it
> to the internet.  It's not like a normal network connection.  They're
> optimized for "minimal upload, maximum download".  This is what aDSL
> does as well (and where the "asymmetric" bit comes in).

There's no such thing as "loop polling" on DSL/cable connections.  Telco
and ISP types tend to call the connection to a remote site a "loop"
because it used to actually be a physical loop of wire out to a remote
site and back (one side was transmit and the other was receive).
Technology changes but terminology doesn't (just like there are
virtually no T-1 lines anymore; they're all DS-1 signallying over either
over SONET fiber rings or HDSL copper pairs).

There's no "polling" going on.

Both DSL and cable DOCSIS technologies support symmetric bit rates, but
asymmetric bit rates (higher down to the customer and lower up to the
ISP) were usually configured because that matched the typical usage
patterns.  This setup goes back to 56k modems (that were only 56k down,
the technology was limited to 31.2k up).

In both DSL and DOCSIS, there is a limit to the total amount of
bandwidth on the wire, and it is just usually configured with more down
to the customer end instead of a 50/50 split.  There's nothing abnormal
about the network connection type; it just allocates bandwidth the way
the majority of customers (still today) use it.

-- 
Chris Adams <cmadams at hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.


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