Key distinction between a libp2p node & a gRPC service architecture

In a libp2p node world, there is no distinct server & client codebases since a node is operating as
a client & as a server simultaneously, making this a key distinction between libp2p and traditional
 client-server model architecture.
 

In libp2p:

  • Peer to Peer Architecture :
    Every node can act as both a client and a server.
    Nodes are referred to as “peers” and they communicate with each other directly
    without requiring a centralized server. This means that any node can initiate connections
    to other nodes as well as accept incoming connections.
     
  • Symmetry :
    Symmetry, in libp2p, means that the same codebase can be used to handle both
    side of the communication. A peer is the network can request resources from other peers
    and provide resources when requested.
     
  • Dynamic Roles : The roles of client & server are not fixed in libp2p and can change
    dynamically based on the context of the communication.
    For instance, a node might acts as a server when it is providing a file to another node but acts as a client when it is downloading a file from a different node.
     

  In contrast , in gRPC:

  • Client-server architecture :
    gRPC typically follows a client-server model where the server provides a set of services
    and the client consuming those services.
    The roles are usually fixed, with the server listening on a port and the client initializing the requests.
     
  • Separate codebases :
    Often the server and client have separate codebases, eventough they
    share the same protocol buffers definitions.
    The server implements the services interfaces, while the client
    use stubs generated from the same protocol buffers to make rpc calls.
     
  • Centralization :
    The gRPC server is a central point that clients connect to which stands
    in radical opposition to the decentralized nature of p2p nodes.

a little bit about the ‘go-libp2p’ library :   The github.com/libp2p/go-libp2p/core/host package is crucial for creating a peer-to-peer network .

  • Host Creation :
    The role of this package is facilitate the creation of a ‘host’. A ‘host’ in libp2p is an abstraction representing a node in the p2p network, acting as a fundamental building block for creating networked applications.
  • Network Interface:
    The Host interface provides the necessary functionality for participating
    in a p2p network. It allows a node to listen for connections from other nodes , initiate connections to other and manage active connections.
  • Identity & Addressing: It also plays a crucial role in managing the node ’s identity(its unique ID in the network) and addresses, essential for other nodes to discover & connect to the host.
  • Stream Multiplexing:
    The package supports stream multiplexing, enabling the host to handle multiple simultaneous data streams over a single connection.
  • Protocol Handling:
    It allows the node to define & implement protocols for communication.
    This is where we can specify how nodes in the network will communicate, what data they will exchange and how this data will be processed.
func createSourceNode() host.Host { 
  // By calling the 'libp2p.New()' function, we initialize a new node.
  node, err := libp2p.New() 
  if err != nil{ 
    log.Fatal(err)
 }
 // We are retuning the node('host.Host') from our 'createSourceNode' function 
 // making it possible to interact with this node elsewhere in the application.
 // This pattern encapsulates the node creation logic and provides a clean interface
 // for node initialization.
 return node 
}