## 4 The Choice of the Blockchain in Social DApps
### Klaytn Blockchain  
Klaytn is a blockchain whose main goal is to enable reliability at the enterprise level. Klaytn uses both public and private blockchain technology in an innovative hybrid model. Public blockchains are used to keep data decentralized, and to facilitate distributed governance. Instead, private blockchains are used to improve scalability and reduce latency, in addition to securing sensitive data. The blockchain utilizes the practical Byzantine fault tolerance (PBFT), an enhanced version of an Instanbul BFT.  
The Klaytn network has a transaction confirmation and block generation time of only one second. This means that the blockchain can process 4000 transactions per second. It also boasts a gas rate of almost 1/10 ETH.  
Klaytn can be partitioned into three logical subnetworks based on their roles and purposes:  
* Service chain network (SCN).
* Endpoint node network (ENN).
* Core cell network (CCN).  
CCN consists of core cells (CCs) that verify and execute transactions submitted through the endpoint nodes (ENs). CCN is responsible for creating and propagating blocks throughout the network. ENN consists of endpoint nodes (ENs) that mainly create transactions, handle RPC API requests, and process data requests from service chains. SCNs are subnetworks composed of auxiliary blockchains independently operated by blockchain applications (BApps). Service chains are connected to the main chain via ENs.  
The core cell network and endpoint node network form a Klaytn main chain, or mainnet. Klaytn has also multiple node types, where each serves a different purpose: consensus node (CN) decides blocks by running consensus; proxy node (PN) is able to protect CNs from adversarial attacks, such as DDoS; finally, endpoint node (EN) serves as an endpoint for the Klaytn network, handling RPC API requests and processing data sent to and from service chains. A core cell (CC) is composed of a single consensus node (CN) and two proxy nodes (PNs). EN nodes form a P2P network called endpoint node network (ENN).  
An important aspect of Klaytn is the Governance Council (GC). GC is \"an alliance of multinational businesses and organizations, responsible for operating the consensus node network and driving the ecosystem growth\" ([[https://medium.com/klaytn/klaytn-governance-council-makerdao-37173c3668d3](https://medium.com/klaytn/klaytn-governance-council-makerdao-37173c3668d3)]([https://medium.com/klaytn/klaytn-governance-council-makerdao-37173c3668d3](https://medium.com/klaytn/klaytn-governance-council-makerdao-37173c3668d3)), accessed on 1 September 2021). Council members can vote on proposals to make changes to the platform, including the development of layer 2 solutions, transaction fee policies, and other structural adjustments. In particular, members of Klaytn GC are responsible for the operation of the Klaytn node network, ensuring consensus is reached for each transaction made on the Klaytn network. Indeed, instead of requiring all nodes to participate consensus, only a random subset of nodes is chosen to run consensus. These nodes are chosen among the GC and they are the consensus nodes, explained above. Nodes use the verifiable random function (VRF) to generate a random value that can be verified cryptographically. For every block generation, Klaytn picks a random number using VRF and identifies a group of nodes, called a committee, to run the consensus protocol. Currently, Klaytn handles more than 4000 transactions per second with only 50 GC nodes.