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title: Small Peer Presence
slug: v4-6/sync/small-peer-presence
docTags: 
createdAt: 2024-02-19T19:56:40.921Z
---

Independent of the internet, Ditto syncs data among peers by establishing sessions and forming a mesh network using all available network transports on a device. In this process, discovered peers create a *presence graph* by advertising and forming connections. 

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# Presence Graph

Much like a conventional city map with roads, the presence graph is like a guide for peers, helping them determine the shortest and fastest paths to route updates from point A to B.

If an intermediate peer becomes unavailable, the presence graph facilitates route updates, ensuring continuous connectivity similar to navigation apps like Google Maps. This flexibility allows the multihop links, established during the *flood-fill process*, to adapt as devices join and leave the mesh network. 

The flood fill process, or *flooding* for short, involves propagating data across connected peers regardless of their queries. For more information, see [Mesh Networking 101](docId:7w61TEGfTlq39qfc8DUsJ).

Represented by different colors in the following graphic, available transports establish multiple active connections simultaneously within the mesh:

![](https://api.archbee.com/api/optimize/qoRkNxW5fJ81r_NqVpc8C/Zhhx_7RIQQi0AAzLHDapB_presence-ov.png)
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# Presence Viewer

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Standard across all of Ditto's demo apps is the *presence viewer*. 

The presence viewer, shown on the right, is a graphical user interface (GUI) built by Ditto that offers a realtime visualization of all connections within your mesh. 

When you launch the viewer, you'll notice that the colors of the lines representing peer-to-peer connections are constantly changing to adapt to the most efficient transports available. 
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![](https://api.archbee.com/api/optimize/qoRkNxW5fJ81r_NqVpc8C/buQUoYvJBiSWaps_HNwFs_presence-ios.png)
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# Security of Connections

Ditto ensures the security of each connection — unlike Bluetooth, which lacks native security measures, Ditto provides end-user devices with certificates signed by a root certificate, allowing identification of connecting devices. 

In addition, all connections are encrypted using Transport Layer Security (TLS) version 1.3. 

:::hint{type="info"}
Approval for NSA-level encryption through collaboration with the military is in progress and expected to be available later this year. For more information, contact Ditto. (See [Human Support](docId\:R-R6Mnu5XSKL0xLrzHCwH))
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