old-www/HOWTO/ATM-Linux-HOWTO/signaling.html

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>Signaling</TITLE
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><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="SIGNALING"
>5. Signaling</A
></H1
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.ATM-HOSTS-FILE"
>5.1. ATM Hosts File</A
></H2
><P
>Because ATM addresses are inconvenient to use, most ATM tools also
accept names instead of numeric addresses. The mapping between names and
numbers is defined in the file <TT
CLASS="FILENAME"
>/etc/hosts.atm</TT
>.
The structure of
this file is similar to the <TT
CLASS="FILENAME"
>/etc/hosts</TT
> file:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN532"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
><TT
CLASS="REPLACEABLE"
><I
>numeric_address</I
></TT
> <TT
CLASS="REPLACEABLE"
><I
>name(s)</I
></TT
></PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
e.g.
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN536"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>47.0005.80FFE1000000F21A26D8.0020EA000EE0.00 pc2-a.fqdn pc2-a
47.0005.80FFE1000000F21A26D8.0020D4102A80.00 pc3-a.fqdn pc3-a</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
></P
><P
>The numeric address can be specified in any of the formats described
in [<A
HREF="bibliography.html#API"
>api</A
>].
The numeric address(es) of a Linux system can be
determined with the command <B
CLASS="COMMAND"
>atmaddr <TT
CLASS="OPTION"
>-n</TT
></B
>
(see also section
<A
HREF="signaling.html#SIGNALING.MANUAL-ADDRESS-CONFIGURATION"
><I
>Manual Address Configuration</I
></A
>).</P
><P
>Many ATM tools also attempt to find the corresponding name when displaying
an address. When translating from the numeric form to a name, the first
applicable name in the file is used.</P
><P
>In addition to ATM addresses for SVCs, also PVC addresses can be stored in
<TT
CLASS="FILENAME"
>/etc/hosts.atm</TT
>.
If different address types are stored under the
same name, the first suitable one will be chosen, i.e. if an application
explicitly requests only SVC addresses, any PVC addresses will be ignored.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.ANS"
>5.2. ANS</A
></H2
><P
>If you have access to the ATM Name Service (ANS, e.g because you've installed
the ANS extension), you can use it instead of or in addition to the hosts
file by specifying the host that runs ANS in the
<TT
CLASS="FILENAME"
>/etc/resolv.conf</TT
> file.</P
><P
>For performing reverse lookups of E.164 addresses, the list of telephony
country codes needs to be known. That list can be obtained from the
<A
HREF="http://www.itu.org/"
TARGET="_top"
>International Telecommunications Union</A
>.
The
<A
HREF="http://www.itu.int/itudoc/itu-t/ob-lists/icc/e164_717.html"
TARGET="_top"
><I
CLASS="CITETITLE"
>List of ITU-T Recommendation E.164 Assigned Country Codes</I
></A
>
is currently available in PDF and Word document formats.
<DIV
CLASS="NOTE"
><P
></P
><TABLE
CLASS="NOTE"
WIDTH="100%"
BORDER="0"
><TR
><TD
WIDTH="25"
ALIGN="CENTER"
VALIGN="TOP"
><IMG
SRC="../images/note.gif"
HSPACE="5"
ALT="Note"></TD
><TH
ALIGN="LEFT"
VALIGN="CENTER"
><B
>NOTE</B
></TH
></TR
><TR
><TD
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>Should the URL become out of date, the document should easily be found by
searching for the document's title at the ITU web site.</P
></TD
></TR
></TABLE
></DIV
></P
><P
>The script
<B
CLASS="COMMAND"
>src/lib/pdf2e164_cc.pl</B
> in the atm-linux distribution can
be used to create the E.164 county codes table with the PDF version
of the country code list, e.g.
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN559"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>perl pdf2e164_cc.pl <TT
CLASS="REPLACEABLE"
><I
>e164_xxx.pdf</I
></TT
> &#62;/etc/e164_cc</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
It should be noted that <SPAN
CLASS="APPLICATION"
>pdftotext</SPAN
> needs to be
available in order to run the script above. It can be obtained with
<A
HREF="http://www.foolabs.com/xpdf/"
TARGET="_top"
><SPAN
CLASS="APPLICATION"
>xpdf</SPAN
></A
>.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.SIGNALING-DEMON"
>5.3. Signaling Demon</A
></H2
><P
>Man pages:
<SPAN
CLASS="CITEREFENTRY"
><SPAN
CLASS="REFENTRYTITLE"
>atmsigd</SPAN
>(8)</SPAN
>
<SPAN
CLASS="CITEREFENTRY"
><SPAN
CLASS="REFENTRYTITLE"
>atmsigd.conf</SPAN
>(4)</SPAN
></P
><P
>Note that <SPAN
CLASS="APPLICATION"
>atmsigd</SPAN
>'s support for point-to-multipoint
is very limited:
only operation as a single leaf of a point-to-multipoint tree works.</P
><P
>By default, <SPAN
CLASS="APPLICATION"
>atmsigd</SPAN
> is configured to conform to
dynamically configure the UNI version. It can be
compiled for UNI 3.0, 3.1, or 4.0 specifically by passing the
<TT
CLASS="PARAMETER"
><I
>--with-uni=VERSION</I
></TT
> to the
<B
CLASS="COMMAND"
>./configure</B
> script in the top-level directory of the
linux-atm source distribution.</P
><P
>Note that <SPAN
CLASS="APPLICATION"
>atmsigd</SPAN
> is configured to be paranoid.
If it detects unusual
problems, it frequently terminates. This will (obviously) change in the
future.</P
><P
><SPAN
CLASS="APPLICATION"
>atmsigd</SPAN
> also looks for a configuration file at the
location specified
with the <TT
CLASS="PARAMETER"
><I
>-c</I
></TT
> option.
The default location is <TT
CLASS="FILENAME"
>/usr/local/etc/atmsigd.conf</TT
>.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.ILMI-DEMON"
>5.4. ILMI Demon</A
></H2
><P
>ILMI provides a mechanism for automatic address configuration. If there is
no switch or if the switch doesn't support ILMI, the ATM addresses must
be configured manually (see section
<A
HREF="signaling.html#SIGNALING.MANUAL-ADDRESS-CONFIGURATION"
><I
>Manual Address Configuration</I
></A
>).
Note that the ILMI
demon should not be used on interfaces where addresses are manually
configured.</P
><P
>The ILMI demon is started as follows:
<P
><B
CLASS="COMMAND"
>ilmid</B
> [-b] [-d] [-i <TT
CLASS="REPLACEABLE"
><I
>local_ip</I
></TT
>] [-l <TT
CLASS="REPLACEABLE"
><I
>log_file</I
></TT
>] [-q <TT
CLASS="REPLACEABLE"
><I
>qos</I
></TT
>] [-u <TT
CLASS="REPLACEABLE"
><I
>uni_version</I
></TT
>] [-v] [-x] [<TT
CLASS="REPLACEABLE"
><I
>itf</I
></TT
>]</P
>
<P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="PARAMETER"
><I
>-b</I
></TT
></DT
><DD
><P
>background. Run in a forked child process after initializing.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-d</I
></TT
></DT
><DD
><P
>enables debugging output. By default, <SPAN
CLASS="APPLICATION"
>ilmid</SPAN
> is very quiet.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-i</I
></TT
> <TT
CLASS="REPLACEABLE"
><I
>local_ip</I
></TT
></DT
><DD
><P
>IP address to tell switch when asked for one.
Can be in either dotted decimal or textual format.
By default, <SPAN
CLASS="APPLICATION"
>ilmid</SPAN
>
uses some heuristics to select a local IP address.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-l</I
></TT
> <TT
CLASS="REPLACEABLE"
><I
>logfile</I
></TT
></DT
><DD
><P
>write diagnostic messages to the specified
file instead of to standard error.
The special name <TT
CLASS="PARAMETER"
><I
>syslog</I
></TT
> is
used to send diagnostics to the system logger.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-q</I
></TT
> <TT
CLASS="REPLACEABLE"
><I
>qos</I
></TT
></DT
><DD
><P
>configures the ILMI VC to use the specified
quality of service. By default, UBR at link speed is used on the ILMI VC.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-u</I
></TT
> <TT
CLASS="REPLACEABLE"
><I
>uni_version</I
></TT
></DT
><DD
><P
>set UNI version. Possible values are
<TT
CLASS="PARAMETER"
><I
>3.0</I
></TT
>,
<TT
CLASS="PARAMETER"
><I
>3.1</I
></TT
>, and
<TT
CLASS="PARAMETER"
><I
>4.0</I
></TT
>. The dot can be omitted. The default
value depends on how <SPAN
CLASS="APPLICATION"
>ilmid</SPAN
> was compiled.
Typically, it is <TT
CLASS="PARAMETER"
><I
>3.0</I
></TT
>.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-v</I
></TT
></DT
><DD
><P
>enables extensive debugging output.</P
></DD
><DT
><TT
CLASS="PARAMETER"
><I
>-x</I
></TT
></DT
><DD
><P
>disable inclusion of variable bindings in the
ColdstartTrap. Some switches (e.g. the LS100) only work if this option is set.</P
></DD
></DL
></DIV
>&#13;</P
><P
>If no interface number is specified, <SPAN
CLASS="APPLICATION"
>ilmid</SPAN
>
serves interface 0.
You can check whether address registration was successful with the
<B
CLASS="COMMAND"
>atmaddr</B
> command (see below).</P
><P
>The agent supports only the address registration procedures specified
in section 5.8 of the ATM Forum's UNI 3.1 specification. These
procedures involve the switch registering the network prefix on the
host and the host registering the final ATM address back on the
switch. The host accomplishes this by appending an ESI (End System
Identifier) and a null selector byte to the network prefix registered
by the switch. The ESI is the physical or MAC address of the ATM
interface.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.MANUAL-ADDRESS-CONFIGURATION"
>5.5. Manual Address Configuration</A
></H2
><P
>If your switch doesn't support ILMI, you have to set the ATM address
manually on the switch and on the PC(s). On the Linux side, make sure that
<SPAN
CLASS="APPLICATION"
>ilmid</SPAN
> doesn't interfere, then use the
<B
CLASS="COMMAND"
>atmaddr</B
> command to set
the address(es).</P
><P
>Man pages:
<SPAN
CLASS="CITEREFENTRY"
><SPAN
CLASS="REFENTRYTITLE"
>atmaddr</SPAN
>(8)</SPAN
></P
><P
>Manual configuration of ATM addresses on the switch depends on the brand.
On a Fore ASX-200, it can be done with the following command:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN674"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>conf nsap route new <TT
CLASS="REPLACEABLE"
><I
>nsap_addr</I
></TT
> 152 <TT
CLASS="REPLACEABLE"
><I
>port</I
></TT
> <TT
CLASS="REPLACEABLE"
><I
>vpi</I
></TT
></PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
e.g.
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN679"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>conf nsap route new 47000580ffe1000000f21510650020ea000ee000 152 1a2 0
|&#60;---- NSAP prefix -----&#62;||&#60;--ESI---&#62;|^^
SEL</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
></P
><P
>The entire NSAP address always has to have a length of 40 digits.
Note that you can also use addresses with a different prefix and an ESI
that doesn't correspond to any ESI your adapters have. The value of the
selector byte (SEL) is ignored.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.RUNNING-TWO-ATM-NICS-BACK-TO-BACK"
>5.6. Running Two ATM NICs Back-to-Back</A
></H2
><P
>It is also possible to run with two ATM NICs connected back-to-back,
and no switch in between.
This is great for simple test environments.</P
><P
>First, if you're using UTP or STP-5, you need a suitable cable. Our
experience with standard 100Base-T back-to-back cables was not
good. It appears that the pin-out they use is different. After some
false starts, we found that the following cable works:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN686"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>RJ45 RJ45
1 ------------ 7
2 ------------ 8
7 ------------ 1
8 ------------ 2
Pins 3, 4, 5, 6 unconnected.</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
A better way to illustrate this may be to show the proper color
schemes for the RJ45 connectors at each end of the back-to-back cable.
The first connector should use the following scheme:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN688"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>RJ45-1
1 - Brown
2 - White/Brown
3 - Unconnected
4 - Unconnected
5 - Unconnected
6 - Unconnected
7 - Orange
8 - White/Orange</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
And the second connector should use this scheme:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN690"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>RJ45-2
1 - Orange
2 - White/Orange
3 - Unconnected
4 - Unconnected
5 - Unconnected
6 - Unconnected
7 - Brown
8 - White/Brown</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>&#13;</P
><P
>You can also make up a loopback cable with 1 -- 7 and 2 -- 8 connected for
ultra-cheap setups.</P
><P
>Here we have two machines called ``virgil'' and ``nestor''.
Substitute your own names as necessary.</P
><P
>One side of the ATM connection needs to use the network version of
<SPAN
CLASS="APPLICATION"
>atmsigd</SPAN
> and the other side should use the
normal user version.
So here on nestor we start <SPAN
CLASS="APPLICATION"
>atmsigd</SPAN
> with:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN697"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>atmsigd -b -m network</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
and on virgil with:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN699"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>atmsigd -b</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
></P
><P
>Without a switch, you won't be able to use ILMI. Instead, create a
<TT
CLASS="FILENAME"
>/etc/hosts.atm</TT
> file containing two dummy addresses.
Our ATM hosts file contains:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN703"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>47.0005.80FFE1000000F21A26D8.0020EA000EE0.00 nestor-atm
47.0005.80FFE1000000F21A26D8.0020D4102A80.00 virgil-atm</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
></P
><P
>These are completely spurious addresses, of course, but as long as you're
not connected to a public or private ATM network, I don't think it matters.
To set the address correctly in the driver, we use:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN706"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>atmaddr -a virgil-atm</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
on virgil, and:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN708"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>atmaddr -a nestor-atm</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>
on nestor. Now start <SPAN
CLASS="APPLICATION"
>atmarpd</SPAN
> on both machines
in the normal way. Now you (should) have a working ATM set-up. To get
IP over ATM working, just follow the instructions in
section <A
HREF="ip-over-atm.html"
><I
>IP Over ATM</I
></A
>.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="SIGNALING.Q-2931-MESSAGE-DUMPER"
>5.7. Q.2931 Message Dumper</A
></H2
><P
>The Q.2931 message compiler also generates a pretty-printer for Q.2931
messages. The executable is called <SPAN
CLASS="APPLICATION"
>q.dump</SPAN
>
is stored in the
<TT
CLASS="FILENAME"
>src/qgen</TT
> directory. Note that it is not copied elsewhere
by <B
CLASS="COMMAND"
>make install</B
>.</P
><P
><SPAN
CLASS="APPLICATION"
>q.dump</SPAN
> expects a sequence of whitespace-separated
hex bytes at standard
input and outputs the message structure if the message can be parsed.
Example:
<DIV
CLASS="INFORMALEXAMPLE"
><A
NAME="AEN720"
></A
><P
></P
><TABLE
BORDER="1"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><FONT
COLOR="#000000"
><PRE
CLASS="SCREEN"
>% echo 09 03 80 00 05 5A 80 00 06 08 80 00 02 81 83 00 48 \
00 00 08 | ./q.dump
_pdsc = 9 "Q.2931 user-network call/connection control message"
_cr_len = 3
call_ref = 8388613 (0x800005)
msg_type = 0x5a "RELEASE COMPLETE"
_ext = 1
_flag = 0 "instruction field not significant"
_action_ind = 0 "clear call"
msg_len = 6 (0x6)
_ie_id = 0x08 "Cause"
_ext = 1
cause_cs = 0 "ITU-T standardized"
_flag = 0 "instruction field not significant"
_action_ind = 0 "clear call"
_ie_len = 2 (0x2)
_ext = 1
location = 1 "private network serving the local user"
_ext = 1
cause = 3 "no route to destination"</PRE
></FONT
></TD
></TR
></TABLE
><P
></P
></DIV
>&#13;</P
></DIV
></DIV
><DIV
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HREF="native-atm-pvcs.html"
>Prev</A
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>IP Over ATM</TD
></TR
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