Due to the complexity of the IKE and IPsec protocols, achieving interoperability in a multivendorenvironment has always been a significant challenge to VPN administrators. In 1998, ICSA Labs addressed this issue by establishing an IPsec Product Developers Consortium and anIPsec Product Certification Testing Program with interoperability as the primary focus.
During the past five years, ICSA Labs analysts have been identifying interoperability problems and determining whether those problems were configuration issues or flaws in the IPsecimplementation of the products. The process has helped to develop the troubleshooting skills and techniques that the analysts rely on every day.
The purpose of this document is to describe troubleshooting techniques to aid VPN administrators in resolving interoperability issues with IPsec products. It is not intended to be a configuration guidance or a best practices document and is vendor neutral.
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