Frequently Asked Questions (FAQ)
How do I see something on the screen?
How do I load files?
Why are some of the controls grey and not available?
How can I see all of the variables for a unit in the Unit
Flow window?
How can I see all of the variables / fields in a unit when
I'm viewing the encapsulation?
Why does the note panel take up so much space?
There are too many packets on top of eachother, is there anything
I can do about it?
Why are the units just horizontal lines on the screen?
What if I want to create my own PEFs?
What does it mean that one of the units has a red border in the encapsulation?
How can show the encapsulation of a particular unit?
Where is the language selection menu?
How does the settings dialog work?
How do I see something on the screen?
You need to load something first. A good choice is loading a pre-designed scenario file (xxx.sce). If none are available, you can also load a protocol events file (yyy.pef), which contains raw protocol data from a recorded protocol exchange. After you have loaded the file, you can press play to see something. You will be looking at the lowest layer of the exchange, and the now-line will begin to move downward and show lines in the message sequence chart as the protocol events occur. Be sure to note that you may well need to make some settings changes if you are looking at a PEF file, because many pef files contain protocol envents that happen very rapidly, and will overlap with the default settings. See other sections in this manual for tips on how to proceed from here.
How do I load files?
Press the load button in the upper left corner of the window, marked with an icon of a folder. After this you need to select wether you want to load a scenario file or a PEF file. The default is scenario file. In some cases there might not be any scenario files available, in this case you will not see anything in the file dialog by default.
Also see the manual section on loading and saving files.
Why are some of the controls grey and not available?
Because they are not relevant or possible actions in the situation you are currently in. Examples of this would be that "play" is not a relevant action if there is no file loaded. Another example would be that it's not possible to press play if you are already playing.
How can I see all of the variables for a unit in the Unit Flow window?
By dragging the note panel divider bar downwards until the variable area is tall enough to show all the variables you need to see.
How can I see all of the variables / fields in a unit when I'm viewing the encapsulation?
Unfortunately it's not possible at this time. The vertical space availble it divided evenly among the relevant layers, and it's not possible to resize the layers. A good option is to view the unit that you want to see in the Unit Flow animation, and see all the variables there.
Why does the note panel take up so much space?
In some cases the note panel will take up the whole vertical space on the right side of the screen by default. You can freely resize the note panel by dragging the divider.
There are too many packets on top of eachother, is there anything I can do about it?
No. However, you can try to alleviate this problem by zooming in until the units are not quite so simultaneous. This zooming is best done by selecting a larger network-to-animation ratio, like the 0.01s -> 1s option for instance. Setting the visual scale is also important in this case. Remember that zooming in to the maximum will cause the rest of the animation to be very tedious to watch. As an example, a millisecond of network time, when viewed up close, will cause 10 seconds of inactivity in the network to seem like a lifetime. Your best option is to take a very small clip of interesting network activity, and record a scenario where this clip is zoomed in, but the rest of the animation is "normal".
Why are the units just horizontal lines on the screen?
Due to the fact that the events happen very quickly in the network, and you are viewing the animation with a very coarse scale. You need to change the scale settings so that these "fast" units are shown with more vertical scale. Once again, remember that the rest of the animation might become a mile long if you set the pixel height to be enormous. See the question about packets on top of eachother for another explanation of this same phenomenon.
What if I want to create my own PEFs?
It's not too difficult, but takes a bit of effort. For this you will need 3 things: a) a network with at least 2 machines (a real network works as well as a simulated, if you know how to simulate a network properly) b) the ability to run tcpdump on these 2 machines simultaneaously. c) the DaCoPAn analyzer program running on a Linux machine to analyze the dumps into a pef file. There is more on this in the specific help of the analyzer. There you can read about the particular tips and tricks you might need to get what you want into the pef.
What does it mean that one of the units has a red border in the encapsulation?
This simply means that it is the unit which you had selected when you pressed the button to show the encapsulation diagram. It is the unit who's encapsulation you are viewing. In practise this means that the unit with the border was the last/newest unit sent from the host at the time of the nowline. For a very technical explanation of exactly how the diagram is generated/selected, see the source code comments of fi.helsinki.dacopan.model.ENCTreeModel.java
How can show the encapsulation of a particular unit?
Two good ways to select which unit to view are
a) when the MSC animation is in pause mode (for instance rewound to the end) you can move the now-line by dragging it with the mouse. This will let you move to the unit who's encapsulation you wish to see.
b) pressing the step buttons can also let you choose which unit is "selected", you can see which unit is selected by looking at the Unit Flow diagram's variable boxes. Remember that the stepping moves through events, not units. So 2 consecutive events might be the sending and then the receiving of the same unit, in both cases that unit will be "selected".
Where is the language selection menu?
The language selection menu has also been translated, so if it is localized into a language that you don't know, you can find it by selecting the fourth menu item from the left. (It might also prove interesting to take a moment or two to learn what the word "language" is in all the localized languages!)
How does the settings dialog work?
It contains one tab for each layer present in the animation, plus one tab for scale setting, and one tab for performance settings.
In the layer sections the idea is to select variables and fields from the 2 listboxes. The left side has the variables which will be represented as columns in the MSC, and the right side has the fields which you can select to be drawn on top of each unit's sequence line in the MSC. Remember that there are limitations to how many of each you can select.
The scale settings are best understood after a small amount of experimentation, because the importance and usefullness of the scale settings depends strongly on the data being viewed. Therefor it is recommended that you play with these settings a little bit in order to best understand their effects.
The performance settings are simply to provide a small amount of configurability in order to help those users who have slightly less processing power to be able to use DaCoPAn efficiently. The animator has been optimized as best as is reasonably possible, but setting the antialiasing can bring further increase in performance if disabled.
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