Corporate.Net internetRx Q: Internet service pro-viders (ISPs) have been contacting me with claims for "Premium Grade" Internet services: They have a higher price tag, but offer guaranteed performance. I am skeptical of these claims, given the shared nature of the Internet. How valid are they? A: You are right to approach these claims with caution. By design, the Internet is a shared resource, providing every user with equal rights to network bandwidth and other available resources. To guarantee resources to a specific user, new protocols that were not part of the initial design must be implemented. Clearly, by reserving resources for one user, these resources are not available to others on the Internet. As the Internet becomes more o f a corporate resource, businesses will require measurable service levels for the money they are paying. The problem lies in getting all of the parties that are delivering Internet services to a gree and cooperate on how these guarantees can be delivered. The most popular protocol for delivering end-to-end guarantees for Internet bandwidth is the Resource Reservation Protocol (RSVP). This protocol relies on RSVP-enabled hosts and routers in the Internet and negotiates a reservation of end-to-end bandwidth before communication starts. In most cases, if a router has its bandwidth committed to existing RSVP communications, it will deny any further requests for bandwidth. ISPs offering performance guarantees argue that they manage their capacity to ensure that RSVP communications or other guaranteed traffic always gets through. If you are using one ISP to supply a virtual private network (VPN) to several locations through that ISP's network, this argument holds water. However, be more cautious when cons idering the purchase of guaranteed Internet resources for general Web browsing. Access to Web sites that may be connected to the Internet via ISP networks (besides the one you use) may not support RSVP requests, or manage their own bandwidth utilization as diligently as your ISP. The Internet still is a work in progress. It is an amazing resource, but cannot be relied on to produce predictable results. If you need guaranteed service, consider implementing your own WAN links or using another commercially run network. Chris Lewis is vice president of international operations at ILX Systems. He is currently working in Europe. He can be reached at chrisl@ilx.com.

Securing Intranet Data With SSL Client Certificates by Robert J Kohlhepp Updated June 27, 1 997