 Hello everyone, good evening. I am Shruti Rupa Banerjee. I work under WAF research at QOLIS and I'm also InfoSecGirl's Pune chapter lead. So basically right now, I will be gossiping about something. It is a protocol, gossip protocol. And why do we call it gossip protocol? Like we can take an analogy, like suppose if I said something about someone or I'm gossiping about someone to one person sitting at this end, in no time the gossip will reach to the other part of the auditorium. Or gossip protocol is also known as epidemic protocol, just like how a disease spreads, how a virus spreads. So why am I talking about this protocol? So you have heard about Amazon S3, Cassandra used in Facebook, React, Database, Bitcoin, so they all use gossip protocol so that an update, a message can be communicated from one note to another note in no time. So this is the basic reason behind gossip protocol. Initially it was used for maintaining consistency of databases by replicating one. Am I audible? So now it is used for various purposes, like for its robust features, for fault tolerance and many more. So there are some ways that three states of gossip protocol, one is susceptible, infected and removed. Taken from the analogy of a disease, if a person is suffering from a disease, he is infected. If a person is not suffering right now and has not got the disease yet, it can be susceptible. But if it has got the disease and now he is completely well, it means it is removed. So based on that, the three states of the gossip protocol, I mean in the gossip protocol, the nodes are defined as such, susceptible that there is no message that has received to the node yet. There is infected node which has received the data yet or the update yet and it is looking for some other node to share that data with and remove that the node has the data, has the update, but is no longer willing to spread the message. So there are three states of gossip protocol, of the nodes of the gossip protocol. So sometimes there are two types like sometimes the nodes can be either susceptible or infected, these are basically models or there can be susceptible, infected and removed. All the three states defined within the model. So there are two ways how you can spread the message to different nodes like one is push style, the other one is pull style and another is push and pull style. Basically if there are different nodes within the network, a node which is infected right now is willing to share the update with other nodes. So it will be pushing the information, the update to other nodes and based on the timestamp and the update, it will be checking if the susceptible node has ever received the update yet. So if it has not, it will get the update and it will be looking for some other node. If it has, then it will be updating that it has received the update already. Within the pull style, the node is an susceptible node is asking for some kind of update, for a new update from other nodes. Again based on the value of the update and the timestamp, it is decided how, whether the node is updated or not. And in push and pull style, it is a combination of both. So I have already said why we are talking about Gossip protocol like Bitcoin miners. If you have heard of miners, that is how they are actually communicating the information that has been updated within the blockchain to all the nodes within the network. So that is how Gossip is used. Apart from that, there is another technology hashgraph which claims that it can be or it may be better than blockchain. It uses Gossip protocol. So we know a lot about the applications that Gossip protocol uses but we don't know about the protocol. So that was from my side about the protocol. If you have any questions, we can talk offline about it. Thank you.