VPN Services For Site-To-Site Connectivity

摘要

Service providers are rolling out IPSec, MPLS and virtual router-based VPN services. Is one of them right for you? Is it time to consider converting your site-to-site WAN to an IP-VPN? To improve network flexibility and reduce operating costs, many large enterprises are evaluating the use of VPN devices, as well as the newer VPN services that have been announced over the past year, including those based on Multiprotocol Label Switching (MPLS), virtual routers and IP Security (IPSec). Even if they have already adopted remote access VPNs, enterprises should come up to speed on the various site-to-site VPN options to determine which best matches their network requirements. Unlike remote access VPNs, which allow Internet-based modem access to enterprise networks and applications, site-to-site VPNs are meant to replace private-line and frame relay connections among enterprise locations. Using VPN products from companies such as Check Point, Cisco and NetScreen, enterprises can "roll their own" IP-VPNs and extend their networks anywhere there is access to the public Internet, often cutting WAN costs by 50 percent or more (see BCR, May 2002, pp. 28-32).