Although there are initiatives underway to provide a level of predictability on the Internet, it may be some time before it is truly a guarantee. Frame relay VPNs today offer a more reliable and predictable solution when the customer's network environment is multi-protocol, particularly if it includes SNA traffic. Many SNA applications run natively on frame relay. Often the types of customers running these large networks are banks, insurance, and manufacturing companies, and their SNA applications are at the core of their business operations. Although they may have an interest in moving the applications to an all IP environment, the reliability and predictability of the frame relay VPN versus a IP-only environment makes frame relay a logical choice for at least the near future.
Security is another concern for users and network managers.
Users want assurances that their VPNs are private and that their applications and communications are isolated and confidential. Where security is critical, such as in the banking industry, users can choose to encrypt their frame relay traffic. IP VPNs make use of encryption and tunneling to provide secure transmissions. While networking equipment utilizing IPSec has helped ease the fears of users and network managers about the security of information traversing the public Internet, scalable and secure enterprise networks based solely on IP may be some years ahead. Large institutions running mission-critical traffic across their network are not likely to make the move to a pure IP VPN model until security is an integral part of protocol support.