[In the case of NAT] There are two patterns depending on the location of NAT

1. Use Cato's SRT (Static Range Translation) feature

There is a way to resolve IP conflicts by utilizing Cato's Static Range Translation (SRT) function. By using SRT, you can maintain the duplicated IP addresses between bases and apply different IPs when communicating between bases. This allows you to avoid IP conflicts.

merit

• Easily avoid IP conflicts.
• It can be set up and managed on the Cato administration screen, so it requires little effort.

Demerit

• Since it cannot be used in conjunction with BGP, limitations arise when route control is required.
• There are restrictions on the use of WAN resiliency features (such as WAN Recovery) and certain protocols (DNS, FTP, SIP).

2. Implement NAT on L3 switches within the base

Another method is to implement NAT on an L3 switch at the site, convert the internal IP address, and register the converted network address in Cato. This method does not use Cato's SRT function, so it can avoid the disadvantages of SRT.

merit

• It avoids SRT restrictions (BGP restrictions and disabling WAN resiliency).
• Flexible NAT rules can be applied, allowing configuration to suit the requirements of each branch office.

Demerit

• Additional configuration of L3 equipment is required, making operation somewhat more complicated.
• Performance checks are required as the load on L3 devices may increase.

[IP addressing organization] This is recommended

Utilizing NAT is an effective short-term solution, but if you consider long-term operation, organizing IP addressing is the recommended method.

By reviewing the IP address system and fundamentally eliminating conflicts, it will be possible to easily expand the network in the future and prevent management from becoming complicated.

Demerit

• Changes to the existing network will be required, resulting in migration costs.
• The entire network needs to be reviewed, and planned reorganization is required.

Summary

The main methods to resolve IP conflicts are to use NAT or to streamline IP addressing. In the short term, using NAT provides immediate relief, but in the long term, streamlining IP addressing is recommended.

NAT options include SRT at Cato PoP and in-site NAT, but each has its own advantages and disadvantages, so it is important to choose the method that best suits your operational environment and requirements.

Ultimately, organizing your IP addresses will provide the most stable operation and will also contribute to future scalability and improved security, so we recommend that you choose this method as a priority if possible.