[Asterisk-Users] FAQ...FXS...LAN...FXO

[Jim Fleming]

----- Original Message ----- 
From: "Brian Johnson" <bjohnson at jecinc.on.ca>
> It's hard to show a proper diagram when you throw in channel banks and the internet
> and start to show the permutations - 
>

If you stick to simple SOHO (Small Office Home Office) configurations, and you assume
that the user has a Phone and a PC, and you put all of the new hardware in one box, then
you may end up with the following.

Phone--------[FXS[**Asterisk**]FXO]----[DSL]-_-_-_-_-_-_-_{Phone Company InterNAT}
PC========[LAN2              LAN1]====[DSL]

The PhoneJack and LineJack have been common FXS and FXO cards (LineJack is both),
but, they started as ISA cards and the LineJack was not migrated to PCI. With commodity
modem hardware for the FXO interface, that part is solved, and the new PCI PhoneJack
can do the FXS function, or multi-port FXS cards can be used. A 4-port FXS card would
be able to handle most homes. Only one person could be using the out-going voice phone
line, but with VOIP via the DSL, everyone could be talking, browsing, etc.

Cost reduction of the [FXS****FXO] box becomes an interesting project as well as inclusion
of the DSL modem. There are many permutations there, because the new 2-slot PCI boxes
mostly have a TV Out interface, which makes it attractive to have the box double as the TV
controller, with DVD and games downloaded. Some people do not like having their phone
service tied to their TV. Now that cellular is more common, that is less of an issue.

To reduce the cost and the system admin headaches of the  [FXS****FXO] box, one can also
envision a box with no hard-drive. A subscription CD (or DVD) could be used to boot the box
and that could include all of the latest software. Some ISPs envision maintaining their customer
base, by having their own CD which expires, that of course requires the moving parts of the
spinning disk, and some prefer to reduce the number of moving parts, including fans.
http://www.knoppix.com
...there are many permutations and trade-offs...but, at the end of the day, the average user just
wants it to work and to provide the service they seek...

Jim Fleming
http://IPv8.isfun.net