Tahoe 971 User Manual - 3.3.2
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4.8. Now it can be loaded using kldload if_th command or by bringing
the interface up: ifconfig th0 up. One interface - th0 - is added when
using one-port card and two interfaces - th0 and th1 - when using two-
port card.
Now the card sould be configured using the sethdlc utility.
3.3.
Using sethdlc
The sethdlc utility is used to configure the WAN card. In case of
FreeBSD drivers it is compiled and installed along with the kernel
modules. In case of Linux drivers it is supplied in a separate file and
additional steps must be followed to install it:
root@linux /usr/src # tar -zxvf sethdlc-1.15t.tar.gz
root@linux /usr/src # cd sethdlc-1.15t
root@linux /usr/src/sethdlc-1.15t # make
root@linux /usr/src/sethdlc-1.15t # make install
3.3.1.
WAN protocol choice
The sethdlc utility may be used to select the protocol used on the
WAN link. Some of the options are available in the Linux driver only.
Under Linux configure the hdlc0 and hdlc1 interfaces and under FreeBSD
- th0 and th1.
¡
transparent HDLC (Linux driver only):
sethdlc hdlc0 hdlc [encoding] [parity]
where:
encoding
nrz nrzi fm-mark fm-space manchester
¡
is one of:
,
,
,
,
parity
no-parity crc16 crc16-pr0 crc16-itu crc16-
¡
:
,
,
,
,
itu-pr0 crc32-itu
,
¡
HDLC treated as an Ethernet interface (Linux driver only):
sethdlc hdlc0 hdlc-eth [encoding] [parity]
parameters same as above
®
¡
Cisco HDLC:
sethdlc hdlc0 cisco [interval value] [timeout value]
where:
interval value
¡
is the time between subsequent keepalive
packets sent through the interface
timeout value
¡
is the time, after which in case of no reception
of keepalive frames the link is treated as unusable
¡
Frame Relay:
sethdlc hdlc0 fr [lmi type [parameter]]
where:
type none ansi ccitt
¡
is the LMI type:
,
,
parameter
dce
(Linux
¡
is a Frame Relay protocol parameter:
only) t391 value t392 value n391 value n392 value n393
,
,
,
,
,
value
Moreover in case of Frame Relay protocol you can create and
delete PVCs (Permanent Virtual Channels) with given DLCI values:
sethdlc hdlc0 create 99
sethdlc hdlc0 delete 99
After creating a PVC, a new interface is created. Under Linux
these interfaces have names pvc0, pvc1 and so on. Under FreeBSD
the name depends on the DLCI number. In the example above a
pvc99 interface would be created
¡
Synchronous PPP:
sethdlc hdlc0 ppp
3.3.2.
Timeslots selection
For a proper operation of the G.703 port you have to specify,
which timeslots are used for transmission. Timeslots can be given in two
ways - as a list of numbers (from 1 to 32) and ranges separated by
commas or as a string of zeros and ones (where '0' means an unused slot
and '1' - an used one, with the first slot at the beginning of the string):
¡ sethdlc hdlc0 slotmap 2-8,20-21,25
¡ sethdlc hdlc0 slotmap 01111111000000000001100010000000
Use of the first timeslot automaticaly enables unframed mode,
where whole 2048 kbps are used for data transfer. Otherwise the first
timeslot is used for framing synchronization. You can also enable the
unframed mode by typing:
sethdlc hdlc0 slotmap all
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