3Com 3COMIMPACT IQ, User Manual

Page: 72 / 160

4-8 C
HAPTER
4: C
ONFIGURATION FOR AN
A
PPLE
M
ACINTOSH
C
OMPUTER
are dialing must also support Multilink PPP, or you will get a
single B channel connection instead of the dual-channel link.
By default, Multilink PPP is enabled. To enable or disable
Multilink PPP, do the following:
1 Click the Multilink check box in the PPP area to clear it
(disable) or check it (enable).
2
Click the
Update Configuration
button to download the
change to your 3C882 ISDN modem’s S register.
Additional configuration may be needed for Multilink PPP. For
details refer to S registers 82 and 83 in Appendix B.
Note that if you disable Multilink PPP (i.e., Register S80=0),
you can still place a Multilink PPP call without changing the
S 80 register value. In the dial string, enter the first telephone
number, then the ampersand character followed by the
second telephone number. For example:
ATD 908 555 1212 & 908 555 1213
Configuring the B Channel Rate
Specify the B channel rate as 56 Kbps, 64 Kbps, or select
TollMizer if you would like to use that feature. TollMizer
allows you to place a 56 Kbps data call using a voice channel,
which is often less expensive. Note that the device you are
calling must also support TollMizer (sometimes referred to as
Switch 56 Permissive or Data Over Voice) to take advantage
of this feature.
By default, the B channel rate is 56 Kbps. Check with your
telephone company for the appropriate B channel rate.
To change the connection speed to 64 Kbps or TollMizer, do
the following:
1
Select the appropriate radio button (64 Kbps or TollMizer).
2
Click the
Update
button to download the change to your
3C882 ISDN modem’s S register.