Pros & Cons Deploying Carrier Grade NAT (CGNAT)

Issues Implementing Carrier Grade NAT

CG-NAT can potentially reduce the performance of applications or services that require end-to-end connections between two or more private networks. Because all packets must traverse through an intermediary device, increased latency and added processing overhead can hinder network performance. Furthermore, peer-to-peer applications and protocols may not function properly over a CG-NAT environment since the connection establishment process may fail due to NAT traversal issues.

Another disadvantage of CG-NAT is related to the visibility and control of traffic flows within an ISP’s network. As all outbound traffic from multiple customers appears to come from a single IPv4 address on the public side of the NAT device, it becomes much more difficult for service providers to track individual user activity and identify malicious activity on their networks. Firewalls or other access control devices deployed downstream become essentially useless since they would have no way of distinguishing between legitimate users and those engaging in illegal activities.

Finally, troubleshooting and debugging can become quite challenging when dealing with CG-NAT deployments due to the complexity involved in configuring these systems. In certain cases, this requires manual intervention from an expert administrator who understands how NAT works as well as how various networking protocols interact at different layers of the stack. This can lead to increased operational costs and downtime while attempting to resolve service outages or other incidents related to NAT misconfigurations or other technical glitches.