Pros of FRR

• Comprehensive routing suite supporting multiple protocols (BGP, OSPF, IS-IS, etc.)
• Mature project with a large community and extensive documentation
• Designed for production use in enterprise and service provider networks

Cons of FRR

• More complex setup and configuration compared to GoBGP
• Heavier resource footprint due to its comprehensive feature set
• Steeper learning curve for newcomers to routing protocols

Code Comparison

FRR configuration example:

router bgp 65000
 neighbor 192.168.1.1 remote-as 65001
 network 10.0.0.0/8

GoBGP configuration example:

[global.config]
  as = 65000
  router-id = "192.168.0.1"

[[neighbors]]
  [neighbors.config]
    neighbor-address = "192.168.1.1"
    peer-as = 65001

FRR offers a more traditional, Cisco-like syntax, while GoBGP uses a TOML-based configuration format. FRR's approach may be more familiar to network engineers, whereas GoBGP's format might appeal to developers and those comfortable with modern configuration languages.

Pros of Ryu

• Written in Python, making it more accessible for rapid development and prototyping
• Extensive support for OpenFlow versions, including 1.0 to 1.5
• Rich set of pre-built components for various network applications

Cons of Ryu

• Generally slower performance compared to GoBGP due to Python's interpreted nature
• Less suitable for high-performance production environments
• Steeper learning curve for developers not familiar with SDN concepts

Code Comparison

Ryu (Python):

from ryu.base import app_manager
from ryu.controller import ofp_event
from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
from ryu.controller.handler import set_ev_cls
from ryu.ofproto import ofproto_v1_3

class SimpleSwitch13(app_manager.RyuApp):
    OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION]

GoBGP (Go):

package main

import (
    "github.com/osrg/gobgp/pkg/server"
    "github.com/sirupsen/logrus"
)

func main() {
    s := server.NewBgpServer()
    go s.Serve()

Pros of Calico

• Comprehensive network policy management for Kubernetes
• Supports multiple data planes (eBPF, Linux, Windows)
• Integrates with various cloud providers and orchestration platforms

Cons of Calico

• More complex setup and configuration compared to GoBGP
• Larger codebase and resource footprint
• Primarily focused on container networking, less versatile for general BGP use cases

Code Comparison

Calico (Go)

func (c *Client) EnsureProfile(ctx context.Context, profile *api.Profile) (*api.Profile, error) {
    // Implementation for ensuring a network profile
}

GoBGP (Go)

func (s *BgpServer) AddPath(ctx context.Context, path *api.Path) error {
    // Implementation for adding a BGP path
}

Both projects use Go and provide APIs for network-related operations. Calico's code focuses on higher-level network policies and profiles, while GoBGP deals with lower-level BGP protocol operations.

Calico is better suited for complex Kubernetes networking scenarios, offering advanced network policies and multi-platform support. GoBGP, on the other hand, is more lightweight and focused specifically on BGP protocol implementation, making it more suitable for general-purpose BGP routing applications outside of container environments.