Jul 24 · 9 min read

Sentinel’s first Cosmos based public testnet, the Sentinel-Turing-1 Testnet, is now live! The launch of this public testnet brings Sentinel closer to the monetized mainnet as the initial validator base is now established. To find out more about the features of this testnet and ongoing development, please scroll further below in the article.

The Sentinel ecosystem has been extremely active in participating in the Tendermint-based consensus framework of the Cosmos Network. Not only is Sentinel actively hosting a validator that is amongst the top 50 Cosmos validators (in terms of voting power), but Sentinel also participated in the Cosmos Game of Stakes and was awarded as one of the top ‘Uptime Leaders’. This participation and involvement in the Cosmos consensus has helped the team understand best-ecosystem practices and also understand a structure for efficient onboarding of validators.

The Sentinel dVPN testnet has been live since the middle of 2018, and so far the network has provided users with over 80TB of bandwidth, powered by community-based node hosts.

The network metrics for the month of June, 2019, truly shows the traction of the dVPN network and the trajectory that the ecosystem is on. With the dVPN network reaching nearly 10,000 sessions in one day and achieving over 170,000 sessions in a period of a month, we can safely conclude that thousands of unique users are using the Sentinel network on a daily basis.

Sentinel dVPN Stats for the month of June 2019

The story so far

Sentinel has publicly been working with Tendermint and the Cosmos SDK from 2018 and has been one of the very first teams to identify the potential, believe in the project and work with it.

Although the Sentinel dVPN dApp was released on Ethereum in 2018, we started work on the Sentinel Zone in the Cosmos Network while planning the architecture as a Hub. The concept of Private Networks was introduced in mid-2018 for a brief period before shifting complete focus to developing the blockchain that powered the network. Finally on December 31, 2018, the first Tendermint testnet, Sentinel Tendermint Testnet v1.1 was released with desktop client v0.1.0.

With Services and Private Networks as part of the Sentinel Network, they communicate not only with each other, but also with other networks within the Cosmos Network. Communication happens primarily to connect chains of multiple Services (dApps on the Sentinel Network), that utilize resources like bandwidth, storage, etc. Holders of BTC, Cosmos (ATOM), ETH, etc. can pay for Services with a token of their choice.

How does the connection between multiple Services & Private Networks happen?

Introducing the Sentinel Hub

Sentinel’s Hub is a chain that is powered by Sentinel’s Validators, elected based on total stake within the network, and are nodes of the network that validate transactions of the Sentinel Hub. Similar to miners in the Bitcoin’s proof-of-work consensus, Sentinel’s Validators are part of a proof-of-stake (POS) network, in which the proposer of a round/leader is elected based on total stake in the network.

The Sentinel Hub facilitates zones that host Sentinel Network Services (SNS). These zones have independent application logic utilizing governance, bank (token transfers & more), staking and other modules from the Sentinel Hub. Sentinel dVPN is a service that runs as a Zone on the Sentinel Hub (more on it later in the article). The zone’s application logic includes protocols pertaining to provable bandwidth consumption and other networking aspects such as Private Nets, etc. reside. This application level or Zone level logic is secured by the Validators of the specific Zone.

For every service running on the Sentinel dVPN, there is a Service Provider & and a Service Consumer. This relationship involves the sharing of resources such as bandwidth and is completely trustless and provable.

This trustlessness is enforced by Sentinel thanks to the provable proof-based resource (bandwidth) measurement protocol. This protocol helps govern activities of Service Providers and Consumers in terms of ensuring accurate bandwidth billing. An implementation of the bandwidth measurement protocol is seen in the Sentinel Tendermint Testnet v1.1 & utilized by the Sentinel dVPN versions v0.1.1 and v0.1.2. The Sentinel dVPN app for Desktop and Mobile (Android only with iOS coming soon) can be downloaded from the project website or the GitHub releases page.

Below is an overview of the Sentinel Network in the Cosmos Hub

Overview of the Sentinel Hub

In the current testnet (Turing-1), applications will run directly on-top of the Sentinel Hub and application logic will be declared at the hub level.

The Sentinel Hub, powered by the Tendermint consensus framework, is developed using the Cosmos SDK and will be interoperable with the Cosmos Network (when Cosmos IBC (Inter Blockchain Communication) is in place).

Zones in the Sentinel Hub

Zones in the Sentinel Hub are independent blockchains which have application-specific logic declared at the consensus level, and these ‘zones’ are either secured by the Validators of the Zone Chain or Validators of the Sentinel Hub (with shared security implemented).

Development of independent Zones is closely associated with the development timeline of Cosmos Inter Blockchain Communication (IBC).

Sentinel’s Zones will be chosen through governance and the Sentinel dVPN is expected to be the first Zone within the Sentinel Network. The Sentinel Hub will handle transactions related to governance, asset transfers, etc. while the Zones handle transactions specific to them — i.e. dVPN transactions in the dVPN Zone and dChat transactions in the dChat Zone.

In the Sentinel-Turing-1 TestNet, the Sentinel Hub is powered by Validators (a maximum of 41) that validate transactions on the network. Each Validator will have certain tasks that will ensure Validator awareness and education is taken care of.

Further documentation will be released pertaining to the economics of a zone, requirements to establish a zone on the Sentinel Hub, and the benefits of having a highly utilized dApp (such as the dVPN) run on its own independent zone.

Sentinel-Turing-1 — Overview, features & expectations


The Sentinel-Turing-1 testnet is launching with only the Sentinel Hub model in place. The first dVPN Zone will be introduced either in upcoming testnets or on the Sentinel mainnet.

Features and related Development for Sentinel-Turing-1

Features of the Sentinel Network that are present in the first iteration of the Sentinel Testnet, Turing-1 are as follows:

  1. Deposits Module
  • Addresses have their own deposits functionality which can be used for bandwidth subscriptions as well as node hosting

A deposit is when tokens are locked for a specific activity (dVPN session) or for a specific time period (subscription for a Service like the Sentinel dVPN). Deposits allow for a pre-paid type model while also ensuring that the users’ funds are not spent unless bandwidth is provably used.

2. VPN Module

  • Service Provider Registration — Service providers can register themselves to start providing Service as part of the Sentinel dVPN network
  • Consumers can subscribe to any dVPN node by depositing any number of coins for use during dVPN sessions
  • Proof based bandwidth exchange between Providers and Consumers

3. Simulation

  • Basic simulation module for the Sentinel Hub has been developed for the testing of the Sentinel Hub

Call for Validators

On the 20th of July 2019, an announcement was made on the official Twitter handle — @sentinel_co inviting potential Validators to submit gentx files to be a part of the first set of Validators to propose blocks on the Sentinel-Turing-1 testnet.

The GitHub branch is now over-subscribed and has received 27 gentx submissions, however the chain will continue with the first 21 Validators as announced earlier. A governance proposal will be issued on the Sentinel-Turing-1 testnet indicating an increase in max_validators.


We currently have submissions from experienced Validators of the Cosmos Network like DragonStake, UbikCapital, WeStaking, Melea, Figment Networks, Bit Cat, Delega Networks, POSBakerz & Forbole (in the order of submission!).

Submission by the organizations and individuals that are interested to Validate on the Sentinel Network few hours before the closing of gentx submissions on 23 July, 2019

Expectation from Validators on Sentinel-Turing-1

The Sentinel-Turing-1 public testnet will have an active governance ecosystem from the very beginning as validators will have to participate in a series of important governance proposals.

Below are tasks that Validators of the Sentinel Network Turing Testnet-1 will go through:

  1. Task #1 — Genesis Validator: Submit gentx
    Post Genesis Validator: Delegate to existing Validator and participate in the process. Instructions on delegation will be up on
  2. Task #2 — Governance Proposal #1: To stop the chain at a specific block
  3. Task #3 — Validators stop the node, update code and restart sentinel-hubd to join Sentinel-Turing-2

The incentivization program for the validators will soon be announced. The ecosystem is already familiar with intelligent methods of incentivization for service provisions (dVPN node host incentive).

In future versions of the Turing-Testnet, validators will be validating real-time dVPN related test transactions in accordance to the dVPN application logic.

Instructions for Validator Setup

Below are instructions to install the sentinel-hub and submit the gentx file.

1) Instructions to install the Sentinel Hub

A step by step text walk-through has been created for the convenience of our validators.


Here is the release on the official Sentinel Hub GitHub repository:

[Video] — Installation of the Sentinel HubVideo on YouTube

2) Be a validator at genesis

Now that the gentx submission pool is oversubscribed, to be a validator post the launch of the Sentinel-Turing-1 testnet please use the below URL to follow instructions and register accordingly.

Follow the URLs below:

[Video] — Be a Genesis ValidatorVideo on YouTube

Text walk-through

NOTE : This is no more a possibility

3) To start the Sentinel-Hub chain

After receiving confirmation of the merged pull request, Validators are required to run the chain before 11am UTC 24 July, 2019 to be part of the genesis.

Below documentation can be utilized after 0930 UTC 24 July, 2019 to start the chain.


4) Be a Validator on the Sentinel-Turing-1 testnet post genesis

Now that the gentx submission pool is oversubscribed, to be a validator post the launch of the Sentinel-Turing-1 testnet please use the below URL to follow instructions and register accordingly.

Text walk-through

Video coming soon.

Timeline of Events

Important dates to note for the submission of the genesis file in prep. for the #SentinelTuring1 TestNet:

1) gentx Submission Start — Already started on 20 July, 2019

2) gentx Submission End — Ended on 1100 UTC 23 July, 2019

3) Genesis Start — From 1100 UTC onwards 24 July, 2019


We support anyone that wants to accept SENT as a payment method, run the Sentinel Private Net for their organization or community or develop tooling for the Sentinel Network. For partnerships of any kind or media enquiries please email —

Join our Community!

About Sentinel Network

Sentinel Network is a network layer that enables a true p2p and decentralized applications and resources marketplace. Sentinel enables anyone to create Public and Private networks that provide access to both free and incentivized, and also payment method agnostic (pre-paid/escrow/post-paid) services (dApps) & distributed resources, enabling its clients to become both producers and consumers in the network.

Sentinel utilizes locking, staking and multi-sig directly from Tendermint core and Cosmos SDK and aims to fully eliminate the disadvantages of previous generation protocols, that couldn’t scale due to limitations of the blockchain they share with other dApps or that have an unsustainable economic model that reduces usability or access to the product they offer.

Follow us on Medium to stay up to date with the latest Sentinel announcements and developments.

View exchanges for trading SENT on the Sentinel website.

Follow Sentinel ONLY ON Official Social Media platforms:

Twitter | Telegram — Official Group | Telegram — Announcements only | Telegram Community Chats — Node Network Group, Chinese, Russian and Spanish


An interoperable networking layer for distributed services. Developed decentralized VPN as first use case. Learn more at


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Interoperable Network Layer for Distributed Resources & Services/dApps. Our #dVPN is the first dApp to utilize our Bandwidth Incentivization Protocol - $SENT



An interoperable networking layer for distributed services. Developed decentralized VPN as first use case. Learn more at

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