Echolink Channel Driver

The chan_echolink channel driver allows PTTLink nodes to register on and communicate with the EchoLink network. The following information is originally from echolink.conf.

echolink.conf

With the addition of the chan_echolink Asterisk channel driver direct connections to and from echolink to Asterisk/app_rpt are now supported. No other programs (e.g. rtpDir, or the link box) are required. With chan_echolink, EchoLink nodes become part of the PTTLink number space.

From an app_rpt/PTTLink node, Echolink connections look just like PTTLink/App_rpt connections except the Echolink node numbers have been prefixed with a 3 and padded out to 7 digits with leading zeroes. For instance, if you want to connect to Echolink node 1234 on your app_rpt system you would dial *3 followed by 3001234. If you have a 6 digit Echolink node number 123456, you would dial *3 followed by 3123456. As you can see we have reserved PTTLink node numbers with a leading 3 for the Echolink number space.

For users originating from an Echolink node using Echolink supplied software, nothing changes for them, they just dial the 4 or 6 digit Echolink node number assigned to your app_rpt system and they get connected!

Setup

First, if you are behind a NAT router, please make sure the ports for Echolink service are correctly forwarded to your asterisk system.

Port To Forward	Service
5198	UDP
5199	UDP
5200	TCP

Additionally, if you are running a firewall and not a consumer grade router which is configured to limit outbound access to a specific number of ports, you must enable UDP outbound access for 5198, and 5199, and TCP outbound access for port 5200.

Current documentation on what ports need to be forwarded can be found on echolink.org in the EchoLink, Firewalls, and Routers section.

To activate the Echolink channel driver, all that's required is a properly formatted configuration file. A base configuration file has been included with Both ACID and Limey Linux and is located in /usr/src/configs/examples/echolink. Copy this file to /etc/asterisk, and edit it to match your callsign, password and node number assignment from Echolink.org. The sample echolink.conf file is as follows:

[el0]
confmode=no           ; Conference mode
call=W6ABC-R          ; Change this to your callsign!
pwd=XXXXX             ; Change this to your password!
name=echolinkusername ; Change this to your real name!
qth=echolink-location ; Change this to your actual QTH!
email=foo@bar.com     ; Change this to your echolink registered email!
maxstns=20            ; The maximum 'at-once' connections allowed/supported (see ** below)
node=123456           ; Change this to the assigned 'ECHOLINK' node# 
astnode=2345          ; Change this to your active PTTLink node number!
context=radio-secure  ; The PTTLink context (leave the default unless you have good reason to change)
server1=server1.echolink.org
server2=server2.echolink.org  
server3=server3.echolink.org
rtcptimeout=10
recfile=/tmp/recorded.gsm
freq=145.000          ; Freq in MHz
tone=100.0            ; CTCSS Tone (0 for none)
lat=34.74978          ; Latitude in decimal degrees
lon=-92.27666         ; Longitude in decimal degrees
power=0               ; 0=0W, 1=1W, 2=4W,  3=9W, 4=16W, 5=25W, 6=36W,  7=49W,  8=64W,  9=81W  (Power in Watts)
height=0              ; 0=10' ,1=20',2=40',3=80' ,4=160' ,5=320' ,6=640' ,7=1280',8=2560',9=5120' (AMSL in Feet)
gain=7                ; Gain in db (0-9)
dir=0                 ; 0=omni, 1=45deg, 2=90deg, 3=135deg, 4=180deg, 5=225deg, 6=270deg, 7=315deg, 8=360deg (Direction)

• • How many stations will your node support ? The 2 most particular factors will be how much CPU/Memory power you have

AND how much bandwidth you have available. So you should not expect a bunch from cpu's under 1ghz or from memory below 1gb.

Once you have made the changes, restart Asterisk, and within a few minutes time, the node should show up on the echolink.org website under Current Logins.

Node Stanza Keys

Note the below go in the node stanza in rpt.conf, not echolink.conf

Key	Valid Values	Default
eannmode	0 = do not announce Echolink nodes at all, 1 = announce only the node number (PTTLink-translated), 2 = announce only the call of the echolink station, 3 = announce both	1
echolinkdefault	0 = telemetry output off, 1 = telemetry output on, 2 = timed telemetry output on command execution and for a short time thereafter, 3 = follow local telemetry mode	2
echolinkdynamic	0 = disallow users to change current echolink telemetry setting with a COP command, 1 = Allow users to change the setting with a COP command	1

Controlling Access

Echolink connections may be denied on a per-callsign basis. This is done by using the deny and permit key values in the above [el0] stanza. The default is to allow all connections if the permit and deny keywords are not present. If a permit is specified, then only the callsigns specified in the permit statement will be allowed to connect. If deny is specified, then the callsign(s) specified will be denied access and the connection will be terminated. Commas are used to delimit multiple callsigns for permit and deny keys. Wildcards are supported so that whole classes of connections can be rejected. Examples:

Examples:

To deny w6xxx you would add the statement: deny=w6xxx

To prohibit computer-based connections you would write: permit=*-*

To allow access to only a select group of callsigns: permit=w6abc,w6def,...

Setting Audio Levels

The audio gain going to and coming from the Echolink system may be set from within a Node Stanza as follows:

erxgain=-3.0      ; defaults to -3.0 db
etxgain=3.0       ; defaults to 3.0 db.

Debugging

The chan_echolink driver supports debugging output.

Debugging can be a activated with the command echolink debug level x (Where x = 0-7. 0=off). With debugging turned on, chan_echolink will output various messages to the terminal related to connecting to nodes, etc.

In addition to turning on debugging, you can use the following commands to query your node's copy of the EchoLink database:

Description	Command
Dump EchoLink database	echolink dbdump
Query EchoLink station by callsign	echolink dbget callsign <EchoLink Callsign> (i.e., KG7QIN-R)
Query EchoLink station by nodename	echolink dbget nodename <EchoLink node number> (i.e., 407301)
Query EchoLink station by ip address	echolink dbget ip <EchoLink node ip address>

Miscellaneous

Connectivity Issues

When debugging EchoLink connectivity issues with your PTTLink node, remember the following:

• Never run the EchoLink application from your mobile device (cell phone/tablet/etc) using the same network as your PTTLink node. This will lead to problems with one or the other not being able to connect to/register/use the EchoLink servers or other EchoLink nodes. (This also applies to running the Windows application on the same network as your PTTLink node).
• If using the EchoLink application on your mobile device (cell phone/tablet/etc), make sure that the EchoLink application is not set to run/is not running in the background. Having the application running in the background can cause problems with your PTTLink node not being able to connect to/register/use the EchoLink servers or other EchoLink nodes.

Note: Same network refers to the the Public IP address that both your PTTLink node AND the device running the EchoLink application are using -- even if they are on different subnets internally.  The Public IP is what the EchoLink servers/network sees and uses when communicating with your node/device.

Caveats

The chan_echolink driver currently:

• Does not send its station info.
• Does not process chat text.
• Only recognizes a few remote text commands.
• Does not have a busy, deaf or mute feature.
• Does not have capacity limits.
• Does not have a banned or private station list. (Access controls are rudimentary and on a per station basis. See Controlling Access)
• Does not have an admin list, only local 127.0.0.1 access.
• Does not have a customizable welcome text message.
• Does not support login or connect timeouts.
• Does not have a max TX time limit.
• Does not support activity reporting.
• Does not have event notifications.
• Does not have any stats.
• Does not have any callsign prefix restrictions.
• Does not announce on connects/disconnects. (Connect/disconnect announcements come from app_rpt's telemetry using the 3xxxxxx node number format)
• Does not have any loop detection.
• Allows "doubles" (newer version of the software are preventing this. Work in progress)

Remote Commands

The following remote text commands can be sent to the chan_echolink driver running on your PTTLink node using netcat:

Command	Function
o.conip <IPaddress>	Request a connect
o.dconip <IPaddress>	Request a disconnect
o.rec	Turn on/off recording