Six good reasons to use IPv6/VSE
Expanded address space
IBM® IPv6/VSE has a dramatically larger address space than IPv4 because it uses a 128-bit address. IPv4 uses only 32 bits. The new address space supports about 3.4 × 1038 addresses. This expansion provides flexibility in allocating addresses and routing traffic. It eliminates the primary need for network address translation (NAT), which gained widespread deployment as an effort to alleviate IPv4 address exhaustion.
More capabilities to simplify procedures
IPv6/VSE implements new features that simplify aspects of address assignment (stateless address auto-configuration) and network renumbering (prefix and router announcements) when changing Internet connectivity providers. The IPv6 subnet size has been standardized by fixing the size of the host identifier portion of an address to 64 bits to facilitate an automatic mechanism for forming the host identifier from Link Layer media addressing information (MAC address).
IPv4 and IPv6 TCP/IP stack
IPv6/VSE provides an IPv4 and IPv6 TCP/IP stack. The IPv6 stack of IPv6/VSE runs in a separate partition using its own stack ID. This allows both an IPv4 and IPv6 stack to run concurrently within one z/VSE system. Running separate IPv4 and IPv6 stacks concurrently within one z/VSE system addresses both performance and reliability aspects. Existing IPv4 applications continue to run unchanged using the IPv4 TCP/IP stack, thus protecting and leveraging existing client investments.
IPv6/VSE contains a basic firewall security facility. The firewall examines IPv4 and IPv6 Ethernet IP packets for basic types of information. The source IP address, packet protocol, TCP or UDP port numbers and ICMP message type and code can be verified and processing accepted or denied.
Dual stack support
IPv6/VSE provides dual stack support. Dual stack support allows an application to connect to both the IPv4 and IPv6 network simultaneously. With the implementation of dual stack support, a single IPv6-enabled CICS transaction or batch application can communicate with partners via either the IPv4 or IPv6 network. Enhanced socket APIs are provided that may be used to introduce IPv6-enabled applications.
IPv6-enabled utility applications
The utility applications provided with the IPv6/VSE product run outside the IPv6/VSE stack partition. Running applications external to the IPv6/VSE stack partition may provide greater stability and better performance. The utility applications that are included with IPv6/VSE include: FTP Server, Batch FTP client, TN3270E Server, NTP Server, NTP Client, Batch Email Client, Batch LPR, Batch Remote Execution Client, Batch PING and REXX automation.