Filters can be set for spots, announcements and WWV. You will find the -directories for these under /spider/filter. You will find some examples in -the directories with the suffix .issue. There are two types of -filter, one for incoming information and one for outgoing information. -Outgoing filters are in the form CALLSIGN.pl and incoming filters -are in the form in_CALLSIGN.pl. Filters can be set for both nodes -and users. +
Starting with version 1.13 there is simple hop control available on a per +node basis. Also it is possible to isolate a network completely so that you +get all the benefits of being on that network, but can't pass on information +from it to any other networks you may be connected to (or vice versa).
-
All filters work in basically the same way. There are several elements -delimited by commas. There can be many lines in the filter and they are -read from the top by the program. When writing a filter you need to think -carefully about just what you want to achieve. You are either going to write -a filter to accept or to reject. Think of a filter as -having 2 main elements. For a reject filter, you would have a line or multiple -lines rejecting the things you do not wish to receive and then a default line -accepting everything else that is not included in the filter. Likewise, for an -accept filter, you would have a line or multiple lines accepting the things you -wish to receive and a default line rejecting everthing else. -
-
In the example below, a user requires a filter that would only return SSB spots -posted in Europe on the HF bands. This is achieved by first rejecting the CW -section of each HF band and rejecting all of VHF, UHF etc based on frequency. -Secondly, a filter rule is set based on CQ zones to only accept spots posted in -Europe. Lastly, a default filter rule is set to reject anything outside the filter. -
-
-
-$in = [
- [ 0, 0, 'r', # reject all CW spots
- [
- 1800.0, 1850.0,
- 3500.0, 3600.0,
- 7000.0, 7040.0,
- 14000.0, 14100.0,
- 18068.0, 18110.0,
- 21000.0, 21150.0,
- 24890.0, 24930.0,
- 28000.0, 28180.0,
- 30000.0, 49000000000.0,
- ] ,1 ],
- [ 1, 11, 'n', [ 14, 15, 16, 20, 33, ], 15 ], #accept EU
- [ 0, 0, 'd', 0, 1 ], # 1 = want, 'd' = everything else
-];
-
--
The actual elements of each filter are described more fully in the following -sections. -
-
The elements of the Spot filter are .... -
-
-
-[action, field_no, sort, possible_values, hops]
-
--
There are 3 elements here to look at. Firstly, the action element. This is -very simple and only 2 possible states exist, accept (1) or drop (0). -
-
The second element is the field_no. There are 13 possiblities to choose from -here .... -
-
-
- 0 = frequency
- 1 = call
- 2 = date in unix format
- 3 = comment
- 4 = spotter
- 5 = spotted dxcc country
- 6 = spotter's dxcc country
- 7 = origin
- 8 = spotted itu
- 9 = spotted cq
- 10 = spotter's itu
- 11 = spotter's cq
- 12 = callsign of the channel on which the spot has appeared
-
--
The third element tells us what to expect in the fourth element. There are -4 possibilities .... -
-
-
- n - numeric list of numbers e.g. [ 1,2,3 ]
- r - ranges of pairs of numbers e.g. between 2 and 4 or 10 to 17 - [ 2,4, 10,17 ]
- a - an alphanumeric regex
- d - the default rule
-
--
The fifth element is simply the hops to set in this filter. This would only -be used if the filter was for a node of course and overrides the hop count in -hop_table.pl. -
-
So, let's look at an example spot filter. It does not matter in the example -who the filter is to be used for. So, what do we need in the filter? We need -to filter the spots the user/node requires and also set a default rule for -anything else outside the filter. Below is a simple filter that stops spots -arriving from outside Europe. +
In /spider/data you will find a file called hop_table.pl. This is the file +that controls your hop count settings. It has a set of default hops on the +various PC frames and also a set for each node you want to alter the hops for. +You may be happy with the default settings of course, but this powerful tool +can help to protect and improve the network. The file will look something +like this ...
-$in = [
- [ 0, 4, 'a', '^(K|N|A|W|VE|VA|J)'], # 0 = drop, 'a' = alphanumeric
- [ 1, 0, 'd', 0, 1 ], # 1 = want, 'd' = everything else
- ];
-
--
So the filter is wrapped in between a pair of square brackets. This tells -Spider to look in between these limits. Then each line is contained within -its own square brackets and ends with a comma. Lets look carefully at the first -line. The first element is 0 (drop). Therefore anything we put on this line -will not be accepted. The next element is 4. This means we are filtering by -the spotter. The third element is the letter "a" which tells the program to -expect an alphanumeric expression in the fourth element. The fourth element -is a list of letters separated by the pipe symbol. -
-
What this line does is tell the program to drop any spots posted by anyone in -the USA, Canada or Japan. -
-
The second line is the default rule for anything else. The "d" tells us this -and the line simply reads... accept anything else. -
-
You can add as many lines as you need to complete the filter but if there are -several lines of the same type it is neater to enclose them all as one line. -An example of this is where specific bands are set. We could write this like -this .... -
-
-
-[ 0,0,'r',[1800.0, 2000.0], 1],
-[ 0,0,'r',[10100.0, 10150.0], 1],
-[ 0,0,'r',[14000.0, 14350.0], 1],
-[ 0,0,'r',[18000.0, 18200.0], 1],
-
--
But the line below achieves the same thing and is more efficient .... -
-
-
- [ 0, 0, 'r',
- [
- 1800.0, 2000.0, # top band
- 10100.0, 10150.0, # WARC
- 14000.0, 14350.0, # 20m
- 18000.0, 18200.0, # WARC
- [ ,1 ],
-
--
-
-
-
+package DXProt;
-# This is an example announce or filter allowing only West EU announces
-#
-# The element list is:-
-# 0 - callsign of announcer
-# 1 - destination * = all, <callsign> = routed to the node
-# 2 - text
-# 3 - * - sysop, <some text> - special list eg 6MUK, ' ', normal announce
-# 4 - origin
-# 5 - 0 - announce, 1 - wx
-# 6 - channel callsign (the interface from which this spot came)
+# default hopcount to use
+$def_hopcount = 5;
-$in = [
- [ 1, 0, 'a', '^(P[ABCDE]|DK0WCY|G|M|2|EI|F|ON)' ],
- [ 0, 0, 'd', 0 ]
-];
+# some variable hop counts based on message type
+%hopcount =
+(
+ 11 => 10,
+ 16 => 10,
+ 17 => 10,
+ 19 => 10,
+ 21 => 10,
+);
+
+
+# the per node hop control thingy
+
+
+%nodehops =
+
+ GB7ADX => { 11 => 8,
+ 12 => 8,
+ 16 => 8,
+ 17 => 8,
+ 19 => 8,
+ 21 => 8,
+ },
+
+ GB7UDX => { 11 => 8,
+ 12 => 8,
+ 16 => 8,
+ 17 => 8,
+ 19 => 8,
+ 21 => 8,
+ },
+ GB7BAA => {
+ 11 => 5,
+ 12 => 8,
+ 16 => 8,
+ 17 => 8,
+ 19 => 8,
+ 21 => 8,
+ },
+};
In this example, only the prefixes listed will be allowed. It is possible to -be quite specific. The Dutch prefix "P" is followed by several secondary -identifiers which are allowed. So, in the example, "PA" or "PE" would be ok -but not "PG". It is even possible to allow information from a single callsign. -In the example this is DK0WCY, to allow the posting of his Aurora Beacon.
-
Each set of hops is contained within a pair of curly braces and contains a +series of PC frame types. PC11 for example is a DX spot. The figures here +are not exhaustive but should give you a good idea of how the file works. +
+
You can alter this file at any time, including whilst the cluster is running. +If you alter the file during runtime, the command load/hops will +bring your changes into effect. +
+
It is possible to isolate networks from each other on a "gateway" node using the +set/isolate <node_call> command. +
+
The effect of this is to partition an isolated network completely from another +nodes connected to your node. Your node will appear on and otherwise behave +normally on every network to which you are connected, but data from an isolated +network will not cross onto any other network or vice versa. However all the +spot, announce and WWV traffic and personal messages will still be handled +locally (because you are a real node on all connected networks), that is locally +connected users will appear on all networks and will be able to access and +receive information from all networks transparently. All routed messages will +be sent as normal, so if a user on one network knows that you are a gateway for +another network, he can still still send a talk/announce etc message via your +node and it will be routed across. +
+
The only limitation currently is that non-private messages cannot be passed down +isolated links regardless of whether they are generated locally. This will change +when the bulletin routing facility is added. +
+
If you use isolate on a node connection you will continue to receive all +information from the isolated partner, however you will not pass any information +back to the isolated node. There are times when you would like to forward only +spots across a link (maybe during a contest for example). To do this, isolate +the node in the normal way and put in a filter in the /spider/filter/spots +directory to override the isolate. This filter can be very simple and consists +of just one line ....
-
-# This is an example WWV filter
-#
-# The element list is:-
-# 0 - nominal unix date of spot (ie the day + hour:13)
-# 1 - the hour
-# 2 - SFI
-# 3 - K
-# 4 - I
-# 5 - text
-# 6 - spotter
-# 7 - origin
-# 8 - incoming interface callsign
-
-# this one doesn't filter, it just sets the hop count to 6 and is
-# used mainly just to override any isolation from WWV coming from
-# the internet.
-
$in = [
- [ 1, 0, 'd', 0, 6 ]
+ [ 1, 0, 'd', 0, 3] # The last figure (3) is the hop count
];
-
It should be noted that the filter will start to be used only once a user/node -has logged out and back in again. -
I am not going to spend any more time on these filters now as they will become -more "comprehensive" in the near future. +
There is a lot more on filtering in the next section.