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Icon	Key	Function	Default State	Comments
	I	Show / hide ONOS cluster instance panel	show	The instance panel is shown by default.
	O	Show / hide ONOS summary panel	show	The summary panel is shown by default.
	D	Disable / enable details panel	enable	The details panel is enabled by default, and is displayed when one or more topology elements are selected. Disabling this panel keeps it hidden even when something is selected.
	H	Toggle host visibility	hide	Shows or hides the hosts (and their links). Hosts are hidden by default.
	M	Toggle offline visibility	show	Devices that are offline (but that ONOS still knows about) are shown by default. This toggle will hide offline devices (and any hosts/links connected to them).
	P	Toggle port highlighting	on	Port highlighting is when hovering the mouse over a link will highlight the link and label the ends with the appropriate port numbers. This feature can be switched off with this toggle.
	B	Toggle background geo map	hide	The background map (hidden by default) can be shown or hidden with this toggle.
Image Added	G	Select background geo map	n/a	Opens a dialog box which allows selection of a geographic region from a pre-defined set.
	S	Toggle sprite layer	hide	The sprite layer (static shapes/text injected into the view) can be shown or hidden with this toggle.

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The background map provides a geographic reference for the topology. The default map is the Continental US. The map layer's visibility can be toggled on and off with the 'B' (for background) key.
See Providing Alternate Maps for the Topology View for additional details.

The scale of background map can be changed on demand. To do that, simply append ?mapscale=<real-number> at the end of the URL. For example,

Custom Sprites

The Topology Sprite Layer mechanism allows custom "background" elements to be displayed (above the background map, but below the topology elements). This could be used, for example, to inject labeled "subnet clouds", or the plan of an office building or campus into the topology view. Typically, one would want to hide the background map layer (press 'B') and show the sprite layer (press 'S') instead.

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