This section contains
- a guided tour based on version 1.0.4 of iBGPlay
- a description of the new features from version 1.0.4 to version 2.0
In the following, we present a typical usage scenario to show the
capabilities of iBGPlay from the user perspective.
When iBGPlay starts, it allows the user to select a set of prefixes.
The panel shows a prefix list initially empty. The user can open a previously saved prefix list or edit the current one (and, later, optionally save it). It also invites the user to choose the interval of time to analyze. The retriever technology allows near real-time update of the database, so it is possible to graphically analyze routing events happened just a few minutes ago. Since iBGPlay can collect data by more than one router, the iBGPlay client allows to easily change among the avaliable points of view (peer). In many cases it is useful to have information about co-location of peering (for example when the router is hosted by an Internet Exchange Point). This can be achieved by instructing iBGPlay on how to aggregate your peerings.
The creation and editing of the prefix list is made easy by the editing window shown in the next figure.
New prefixes can be
- directly inserted by the user in the form ip-address/mask (IP Prefix);
- selected as the less specific prefix, announced in the Internet, containing a certain IP address (this IP address can also be specified as a DNS name, for example you can submit the name of a famous web site).
- announced to the router with a certain next hop (Next Hop, specified by IP address or by DNS name);
- originated by a certain AS (AS Origin, specified numerically);
- announced to the router by a certain AS (AS Announcer, specified numerically).
When your prefix list is ready, you can graphically view the routing evolution in the specified time interval. An example of graphical output is shown in the Following figure (click to enlarge).
The left part of the window contains a green/purple activity graph which plots the number of events over time on a logarithmic scale. Green peaks shows re-annuncements of already known routing informations, while purple peaks represent real routing changes. The bottom of the graph corresponds to the start of the query interval and the top of the graph to the end; the small blue triangle indicates the time whose routing state is currently visualized in the main part of the window.
The main part of the window contains the AS graph. Each number represents an AS, and the red circle represent the router you choose. You may move ASes around by dragging them with the mouse. For information about an AS, simply click on it: its name and description will appear at the top of the window. The ASes originating the prefixes you selected are displayed in blue.
Each line represents an AS path. Each path connects the central router to the originating AS. Ideally, you might see one path for each prefix of your list. However, the visualization would be culttered and very hard to read. Prefixes that are stable during the query interval and have the same AS-path are shown with one single dashed path. The solid lines represent paths that did change during the query interval. Prefixes that behave the same during the query interval are grouped in an "equivalence class" and shown with a single paht as they would be one prefix.
The paths are drawn in different colours to ensure that each AS-path connecting central router to the originating AS can be unambiguously identified; the colour itself has no special meaning.
Each node adjacent to the central router represents a next-hop. More next-hops can be aggregated into a single node to express that the peerings are performed in an Internet Exchange Point. Such aggregation is statically configured in a file that can be selected from the main query form.
The routing state at each instant of the query interval can be shown by clicking on the corresponding point of the time chart on the left. You can use the "<" and ">" buttons to move to the previous and next routing events. For each routing event, iBGPlay displays an animation and updates the AS graph. Information on the current routing event can be found at the top of the window. If the event involve an equivalence class the prefixes of it can be shown It is possible to show the prefixes originated by each AS and how they are partitioned into equivalence classes by means of the "show prefixes" button.
If you intend to continously monitor a set of hot prefixes you can launch a Dashboard from the main query panel. In a dashboard the visualization is automatically refreshed each 30 seconds (configurable) or the refresh can be manually forced. The last routing status is always visualized and the activity graph on the left shows activity for the last day, week or month (user selectable). In the case that a dashboard view is particularly interesting, the Explore button launch an equivalent interactive panel where the user can animate the routing events as described above. The following picture shows a typical dashboard visualization (click to enlarge).
NEW FEATURES from Version 1.0.4 to 2.0The main feature of release 2.0 of iBGPlay is the capability of showing routing information of several routers in the same view. Now, you can use iBGPlay to visually compare the routing of your border gateways. To guarantee a clear view in this new setting, iBGPlay has been improved with new visualization and interactions paradigms.
Changes to the Query FormFirst of all, version 2.0 allows the user to select more than one router using the main query form (see picture below, selected routers are shown in the right list). The remaining part of the form and the queries for building the list of prefixes did not changed from the previous release.
Changes to Routing VisualizationGraphical visualization of routing status and events has undergone major changes. Where the iBGPlay user is used to see one red node in the middle of its view, now he/she can see many of them (depending on the choice done in the main query panel).
Semantic of dashed and solid lines is unchanged, but for the consideration that for a single prefix the number of AS-paths shown can be more than one. Namely, routes collected by different routers are treated as if they where different prefixes. So, if in version 1.0.4 you can have at most one AS-path for each prefix, now, if you ask for N routers, you can have up to N distinct AS-paths shown for each prefix.
The possibility to have many routers in your visualization, puts in the drawing much more information than before, possibly confusing the user and leading to tangled drawings. To help the user, iBGPlay has been equipped with an interactive selection mechanism, that allows the user to highlight the relevant information shadowing the other.
Router HighlightingWhen the user clicks on one router, it becomes selected. When a router is selected the following things happen (see figure below).
- The selected router is evidenced by a rounded black border.
- For each prefix, only the AS-paths for routes collected by the selected router are normally shown.
- All other AS-paths are shown in gray.
During animation of events, all events for gray paths are skipped. The time panel (on the left) shows in gray the total density of routing events. The density of routing events related to non-gray AS-paths are shown with usual semantic in magenta (routing changes) and green (re-announcements).
AS HighlightingWhen the user clicks on an AS which announce prefixes that you put in the list, that AS becomes selected. When an AS is selected the following things happen (see figure below).
- Only the AS-paths related to prefixes announced by the selected AS are normally shown.
- All other AS-paths are shown in gray.
Also in this case event animation skips the events related to gray paths, and time panel shows in magenta/green only events density for interesting routes.
Internal Routing VisualizationSuppose you see in the drawing that two routers (R1 and R2) reach a destination (Dest) through certain next-hops (nh) as shown below.
R1 \ nh---1200---3400---5600---Dest / R2However, only one router between R1 and R2 is directly connected with nh. Suppose R1 is connected to nh, in many configurations R2 reaches nh through R1. So a more expressive visualization would be the following.
R1 | \ | nh---1200---3400---5600---Dest | R2iBGPlay can graphical show this as you can see from the picture above (for example the AS paths traversing routers shown in pink). To obtain this result, you have to tell to iBGPlay which next-hops are connected with which of the ISP's routers by means of a simple configuration file. The iBGPlay provides semi-automatic aid to create that configuration with a documented procedure.