From DXSpider version 1.48, major changes were introduced to the way -node connections are treated. This is part of an ongoing process to -remove problems with loops and to enable talk and other functions to -propagate across the whole of the worldwide cluster network. In fact, -in a Spider network, it would be useful, perhaps even necessary to -have loops. This would give real resilience to the network, meaning -that if a link dropped, the information flow would simply come in and -go out via a different route. Of course, we do not have a complete -network of Spider nodes, there are other programs out there. Some of -these do not have any protection from loops. Certainly AK1A does not -handle loops well at all. It is therefore necessary to have some form -of protection for these nodes.
- -In fact DXSpider has had a simple system for some time which is called -isolation. This is similar to what in other systems such as -clx, is called passive mode. A more detailed explanation -of isolation is given further below. This system is still available -and, for simple networks, is probably all that you need.
- -The new functionality introduced in version 1.48 allows filtering the node -and user protocol frames on a "per interface" basis. We call this -route filtering. This is used instead of -isolation.
- -What this really means is that you can control more or less completely -which user and node management PC protocol frames pass to each of your -partner nodes. You can also limit what comes into your node from your -partners. It is even possible to control the settings that your partner -node has for the routing information that it sends to you -(using the rcmd command).
- -Initially when route filters were being tested we generated a -"default" filter. Unfortunately it quickly became apparent that this -might suit the UK cluster network but didn't really fit anybody else. -However using a default filter is an appropriate thing to do. How, is -explained further on.
- -The first thing that you must do is determine whether you need to use -route filtering at all. If you are a "normal" node with two or -three partners and you arranged in an "official" non-looping tree type -network, then you do not need to do route filtering and you will -feel a lot better for not getting involved. If you are successfully using -isolation then you also probably don't need to use route filtering.
- -To put it simply, you should not mix Isolation and Route Filtering. It -will work, of sorts, but you will not get the expected results. If you -are using Isolation sucessfully at the moment, do not get involved in -Route Filtering unless you have a good supply of aspirin! Once you have -started down the road of Route Filtering, do not use Isolation either. -Use one or the other, not both.
- -You will only require this functionality if you are "well-connected". What -that means is that you are connected to several different parts of (say) -the EU cluster and, at the same time, also connected to two or three places -in the US which, in turn are connected back to the EU. This is called a -"loop" and if you are seriously looped then you need filtering.
- -I should at this stage give a little bit of background on filters. All -the filters in Spider work in basically the same way. You can either -accept or reject various options in order to create the filter rules -you wish to achieve. Some filters are user settable, others can only -be altered by the sysop. Route filtering can only be done by the sysop.
- --Anyway, without further discouragement, let me start the process -of explanation.
- -All normal systems should have a default routing filter and it should -usually be set to send only the normal, unlooped, view of your -"national" network. Here in the UK that means nodes from the UK and -Eire, in EU it is more complex as the networks there grew up in a more -intertwined way.
- --The generic commands are:-
--
-
-reject/route node_default <filter_option>
-
-or
-
-accept/route node_default <filter_option>
-
-where filter_option is one of the following ...
--
-
-call <prefixes>
-call_dxcc <numbers>
-call_itu <numbers>
-call_zone <numbers>
-channel <prefixes>
-channel_dxcc <numbers>
-channel_itu <numbers>
-channel_zone <numbers>
-
-Please be careful if you alter this setting, it will affect -ALL your links! Remember, this is a default -filter for node connections, not a per link default.
- -For the default routing filter then you have two real choices: either -a "national" view or the "safe" option of only your own -callsign. Examples of each (for my node: GB7DJK) are:-
--
-
-acc/route node_default call_dxcc 61,38
-acc/route node_default call gb7djk
-
-GB7DJK uses the first of these. The DXCC countries can be obtained from the -show/prefix command.
- -The example filters shown control output TO all your -partner nodes unless they have a specific filter applied to them (see -next section).
- -It is also possible to control the incoming routing -information that you are prepared to accept FROM your partner -nodes. The reason this is necessary is to make sure that stuff like -mail, pings and similar commands a) go down the correct links and b) -don't loop around excessively. Again using GB7DJK as an example a typical -default input filter would be something like:
--
-
-rej/route node_default input call_dxcc 61,38 and not channel_dxcc 61,38
-
-What this does is accept node and user information for our national -network from nodes that are in our national network, but rejects such -information from anyone else. Although it doesn't explicitly say so, -by implication, any other node information (not from the UK and Eire) -is accepted.
- -As I imagine it will take a little while to get one's head around all of -this you can study the effect of any rules that you try by watching the -debug output after having done:-
--
-
-set/debug filter
-
-After you have got tired of that, to put it back the way it was:-
--
-
-unset/debug filter
-
-Exactly the same rules apply for general route filtering. You would -use either an accept filter or a reject filter like this ...
--
-
-reject/route <node_call> <filter_option>
-
-or
-
-accept/route <node_call> <filter_option>
-
-Here are some examples of route filters ...
--
-
-rej/route gb7djk call_dxcc 61,38 (send everything except UK+EIRE nodes)
-rej/route all (equiv to [very] restricted mode)
-acc/route gb7djk call_dxcc 61,38 (send only UK+EIRE nodes)
-acc/route gb7djk call gb7djk (equiv to SET/ISOLATE)
-
-In practice you will either be opening the default filter out for a -partner by defining a specific filter for that callsign:-
--
-
-acc/route gb7baa all
-acc/route gb7baa input all
-
-or restricting it quite a lot, in fact making it very nearly like an -isolated node, like this:-
--
-
-acc/route pi4ehv-8 call gb7djk
-rej/route pi4ehv-8 input call_dxcc 61,38
-
-This last example takes everything except UK and Eire from PI4EHV-8 -but only sends him my local configuration (just a PC19 for GB7DJK and -PC16s for my local users).
- -It is possible to write much more complex rules, there are up -to 10 accept/reject pairs per callsign per filter. For more information -see the next section.
- - -Upto v1.44 it was not possible for the user to set their own filters. From -v1.45 though that has all changed. It is now possible to set filters for just -about anything you wish. If you have just updated from an older version of -DXSpider you will need to update your new filters. You do not need to do -anything with your old filters, they will be renamed as you update.
- -There are 3 basic commands involved in setting and manipulating filters. These -are accept, reject and clear. First we will look -generally at filtering. There are a number of things you can filter in the -DXSpider system. They all use the same general mechanism.
- -In general terms you can create a "reject" or an "accept" filter which can have -up to 10 lines in it. You do this using, for example ...
--
-
-
-accept/spots .....
-reject/spots .....
-
-where ..... are the specific commands for that type of filter. There are filters -for spots, wwv, announce, wcy and (for sysops) connects. See each different -accept or reject command reference for more details.
-There is also a command to clear out one or more lines in a filter. They are ...
--
-
-clear/spots 1
-clear/spots all
-
-There is clear/xxxx command for each type of filter.
- -and you can check that your filters have worked by the command ...
--
-
-
-show/filter
-
-For now we are going to use spots for the examples, but you can apply the same -principles to all types of filter.
- -There are two main types of filter, accept or reject. You -can use either to achieve the result you want dependent on your own preference -and which is more simple to do. It is pointless writing 8 lines of reject -filters when 1 accept filter would do the same thing! Each filter has 10 -lines (of any length) which are tried in order. If a line matches then the -action you have specified is taken (ie reject means ignore it and accept -means take it)
- -If you specify reject filters, then any lines that arrive that match the filter -will be dumped but all else will be accepted. If you use an accept filter, -then ONLY the lines in the filter will be accepted and all else will be dumped. -For example if you have a single line accept filter ...
--
-
-accept/spots on vhf and (by_zone 14,15,16 or call_zone 14,15,16)
-
-then you will ONLY get VHF spots from or to CQ zones -14, 15 and 16.
- -If you set a reject filter like this ...
--
-
-reject/spots on hf/cw
-
-Then you will get everything EXCEPT HF CW spots. You could make this -single filter even more flexible. For example, if you are interested in IOTA -and will work it even on CW even though normally you are not interested in -CW, then you could say ...
--
-
-reject/spots on hf/cw and not info iota
-
-But in that case you might only be interested in iota and say:-
--
-
-accept/spots not on hf/cw or info iota
-
-which achieves exactly the same thing. You should choose one or the other -until you are comfortable with the way it works. You can mix them if you -wish (actually you can have an accept AND a reject on the same line) but -don't attempt this until you are sure you know what you are doing!
- -You can arrange your filter lines into logical units, either for your own -understanding or simply convenience. Here is an example ...
--
-
-reject/spots 1 on hf/cw
-reject/spots 2 on 50000/1400000 not (by_zone 14,15,16 or call_zone 14,15,16)
-
-What this does is to ignore all HF CW spots and also rejects any spots on VHF -which don't either originate or spot someone in Europe.
- -This is an example where you would use a line number (1 and 2 in this case), if -you leave the digit out, the system assumes '1'. Digits '0'-'9' are available. -This make it easier to see just what filters you have set. It also makes it -more simple to remove individual filters, during a contest for example.
- -You will notice in the above example that the second line has brackets. Look -at the line logically. You can see there are 2 separate sections to it. We -are saying reject spots that are VHF or above APART from those in -zones 14, 15 and 16 (either spotted there or originated there). If you did -not have the brackets to separate the 2 sections, then Spider would read it -logically from the front and see a different expression entirely ...
--
-
-(on 50000/1400000 and by_zone 14,15,16) or call_zone 14,15,16
-
-The simple way to remember this is, if you use OR - use brackets. Whilst we are -here CASE is not important. 'And BY_Zone' is just the same as 'and by_zone'.
-As mentioned earlier, setting several filters can be more flexible than -simply setting one complex one. Doing it in this way means that if you want -to alter your filter you can just redefine or remove one or more lines of it or -one line. For example ...
--
-
-reject/spots 1 on hf/ssb
-
-would redefine our earlier example, or
--
-
-clear/spots 1
-
-To remove all the filter lines in the spot filter ...
--
-
-clear/spots all
-
-You can filter in several different ways. The options are listed in the -various helpfiles for accept, reject and filter.
- -Sometimes all that is needed is a general rule for node connects. This can -be done with a node_default filter. This rule will always be followed, even -if the link is isolated, unless another filter is set specifically. Default -rules can be set for nodes and users. They can be set for spots, announces, -WWV and WCY. They can also be used for hops. An example might look like -this ...
--
-
-accept/spot node_default by_zone 14,15,16,20,33
-set/hops node_default spot 50
-
-This filter is for spots only, you could set others for announce, WWV and WCY. -This filter would work for ALL nodes unless a specific filter is written to -override it for a particular node. You can also set a user_default should -you require. It is important to note that default filters should be -considered to be "connected". By this I mean that should you override the -default filter for spots, you need to add a rule for the hops for spots also.
- -Once you are happy with the results you get, you may like to experiment.
- -The previous example that filters hf/cw spots and accepts vhf/uhf spots from EU -can be written with a mixed filter, for example ...
--
-
-rej/spot on hf/cw
-acc/spot on 0/30000
-acc/spot 2 on 50000/1400000 and (by_zone 14,15,16 or call_zone 14,15,16)
-
-Note that the first filter has not been specified with a number. This will -automatically be assumed to be number 1. In this case, we have said reject all -HF spots in the CW section of the bands but accept all others at HF. Also -accept anything in VHF and above spotted in or by operators in the zones -14, 15 and 16. Each filter slot actually has a 'reject' slot and -an 'accept' slot. The reject slot is executed BEFORE the accept slot.
- -It was mentioned earlier that after a reject test that doesn't match, the default -for following tests is 'accept', the reverse is true for 'accept'. In the example -what happens is that the reject is executed first, any non hf/cw spot is passed -to the accept line, which lets through everything else on HF. The next filter line -lets through just VHF/UHF spots from EU.
- -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 ...
--
-
-#
-# hop table construction
-#
-
-package DXProt;
-
-# default hopcount to use
-$def_hopcount = 5;
-
-# 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,
- },
-);
-
-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.
- -SHould any of the nodecalls include an ssid, it is important to wrap the -whole call in single quotes, like this ...
--
-
- 'DB0FHF-15' => {
- 11 => 5,
- 12 => 8,
- 16 => 8,
- 17 => 8,
- 19 => 8,
- 21 => 8,
- },
-
-If you do not do this, you will get errors and the file will not work as -expected.
- -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.
- -You can set a callsign specific hop count for any of the standard filter -options so:-
--
-
-set/hops gb7djk spot 4
-set/hops node_default route 10
-set/hops gb7baa wcy 5
-
-all work on their specific area of the protocol.
- -The set/hops command overrides any hops that you have set otherwise.
- -You can show what hops have been set using the show/hops command.
- -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 -node 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.
- -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 use -an acc/spot >call< all filter to override the isolate.
- -