Sign in Subscribe

CER (Customer Edge Router)

Last updated on 

A Customer Edge Router (CER) is a network device that connects a customer's network to a service provider's network. It is typically located at the edge of the customer's network and is responsible for routing traffic to and from the service provider's network.

CERs are an essential component of any modern network infrastructure, enabling businesses to connect their networks to the internet and other external networks securely and efficiently. In this article, we will explore the various aspects of CERs, including their functions, features, and deployment options.

Functions of a Customer Edge Router

A CER performs several essential functions, including:

  1. Packet forwarding: A CER is responsible for forwarding packets between the customer's network and the service provider's network. It performs this function by examining the destination IP address of each packet and routing it to the appropriate destination.
  2. Network Address Translation (NAT): CERs often perform NAT to allow multiple devices on the customer's network to share a single public IP address. NAT translates the private IP addresses used on the customer's network into a public IP address that can be used on the internet.
  3. Quality of Service (QoS): CERs can prioritize traffic based on its type, source, or destination. This allows businesses to ensure that critical traffic, such as voice or video, receives sufficient bandwidth and latency to function properly.
  4. Virtual Private Network (VPN) connectivity: Many CERs support VPN connections to enable secure communication between remote locations or employees.
  5. Firewalling: A CER can also function as a firewall, protecting the customer's network from unauthorized access and malicious traffic.

Features of a Customer Edge Router

CERs are designed with several features that enable them to perform their functions effectively. Some of these features include:

  1. High Availability: CERs typically include redundancy features such as hot standby or failover to ensure that network connectivity is maintained in the event of a hardware or software failure.
  2. Scalability: CERs can handle increasing amounts of traffic as the customer's network grows. They are designed to support multiple routing protocols and interfaces, enabling businesses to scale their networks as needed.
  3. Security: CERs include security features such as VPN support, firewalling, and intrusion prevention to protect the customer's network from threats.
  4. Management: CERs can be managed remotely using various protocols such as SNMP, Telnet, or SSH. This allows network administrators to configure, monitor, and troubleshoot the device from a central location.

Deployment Options for a Customer Edge Router

CERs can be deployed in various ways depending on the customer's network architecture and requirements. Some common deployment options include:

  1. Standalone deployment: In a standalone deployment, the CER is installed as a dedicated device at the edge of the customer's network. This deployment is suitable for small to medium-sized businesses with a single site.
  2. Redundant deployment: In a redundant deployment, two or more CERs are installed in a high availability configuration to provide failover and redundancy. This deployment is suitable for businesses with critical network infrastructure that requires high availability.
  3. Virtual deployment: In a virtual deployment, the CER is installed as a virtual machine on a server or cloud platform. This deployment is suitable for businesses that want to reduce hardware costs or require flexibility in their network infrastructure.
  4. Managed service deployment: In a managed service deployment, the CER is provided as a managed service by the service provider. This deployment is suitable for businesses that want to outsource the management and maintenance of their network infrastructure.

Conclusion

A Customer Edge Router is a crucial component of any network infrastructure that connects a customer's network to a service provider's network. It performs several essential functions, including packet forwarding, NAT, QoS, VPN connectivity, and firewalling. CERs also include features such as high availability, scalability, security, and management, enabling businesses to ensure their network is reliable, secure, and efficient.

CERs can be deployed in various ways depending on the customer's network architecture and requirements. Some common deployment options include standalone, redundant, virtual, and managed service deployment.