|
[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]
> Date: Sat, 23 Mar 2002 02:02:56 -0500 (EST)
> From: Doug Crompton <wa3dsp@crompton.com>
>
> I stopped at a local ISP today, trying to get some options on high(er)
> speed connections being that xDSL is not available to me. ISDN came up. It
> looks like I could get a 2B 128/128 24/7 ISDN static IP for about
> $120/month - that is in line with what it looks like I would pay for an
> IDSL 144/144 if it were available.
>
> Also mentioned were 56K frame relay and fractional T1 - 128K both of which
> are more expensive.
>
> Does anyone have experience with ISDN? Are the data rates constant? Do
> they negotiate lower for poorer lines? What would the interface for a 2B
> be from modem to computer? Does linux play weel with it?
>
> ISDN is now flat rate in Verizon so no minute charges apply.
>
> I did some trolling on the internet and I see that a company in Washington
> state has 2B 128/128 for $44/month with many Philly exchanges covered. I
> would have to think some additional charges apply - like the charges for
> your two additonal phone lines. Does verizon charge the same as voice
> lines for those?
>
> http://www.eskimo.com/services/isdn.html
>
Important thing to remember -- ISDN is a TARIFFED data service.
Unlike DSL service, ISDN service is GUARANTEED to be 128/128 all the time
and it really is! And if it isn't, Bell (or whoever) will fix it. No
worries about, "we don't support anyting over 2400 baud."
However, also unlike DSL, your "destination" must be able to answer an
incoming ISDN call. Many ISPs do not have that capability, and will charge
you substantially more for an ISDN based connection because of that -- ie
You are paying for THEIR ISDN service as well as yours! ISDN service does
not have a "cloud" like SMDS or DSL. It is a point-to-point, switched
service. Even though ISDN is a dial service, you cannot simply dial
somebody's POTS line. You can only dial another ISDN line... but you CAN
dial ANY ISDN line in the world.
DSL over ISDN is a "normal" product for many ISPs. You can actually get a
slightly higher baud rate by "nailing-up" your ISDN connection to one
receiving phone number and then combining the two primary channels and the
signaling channel (B). Otherwise you can only combine the two primary
channels. This was a regular product offered by COVAD at one time, I don't
know if they still offer it or not.
If they have finally made ISDN flat rate, then it is a good deal, otherwise
it is VERY expensive.
The other nice thing about ISDN and DSL over ISDN -- there is NO distance
limit!!! ISDN can work over virtually infinite distances.
As for Linux working with ISDN -- Why bother!?! Put it another way. ISDN is
a serial line connection, just like DSL. There is no rational reason to
convert your Linux box into an ISDN modem. Sure you CAN do it, but why
waste the CPU cycles on all of the ISDN overhead. Let the modem do the job.
Older ISDN modems only offered and RS232 output connection -- most
contemporary ISDN modems offer an Ethernet port.
--
T.T.F.N.
William H. Magill Senior Systems Administrator
Information Services and Computing (ISC) Networking & Telecommunications
University of Pennsylvania
magill@isc.upenn.edu magill@acm.org
http://www.isc-net.upenn.edu/~magill/ magill@mcgillsoceity.org
______________________________________________________________________
Philadelphia Linux Users Group - http://www.phillylinux.org
Announcements-http://lists.phillylinux.org/mail/listinfo/plug-announce
General Discussion - http://lists.phillylinux.org/mail/listinfo/plug
|
|