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About NPTv6
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Next-Generation Firewall

About NPTv6

Table of Contents
Learn more about IPv6-to-IPv6 Network Prefix Translation (NPTv6) for your managed firewalls.
Contact your account team to enable Cloud Management for NGFWs using Strata Cloud Manager.
Where Can I Use This?What Do I Need?
One of these:
Configure a Network Address Translation (NAT) policy rule to perform IPv6-to-IPv6 Network Prefix Translation (NPTv6). Palo Alto Networks doesn’t implement all functionality defined in the RFC, but is compliant with the RFC in the functionality it has implemented.
NPTv6 performs stateless translation of one IPv6 prefix to another IPv6 prefix. It’s stateless, meaning that it doesn’t keep track of ports or sessions on the addresses translated. NPTv6 differs from NAT66, which is stateful. Palo Alto Networks supports NPTv6 RFC 6296 prefix translation; it doesn’t support NAT66.
With the limited addresses in the IPv4 space, NAT was required to translate private and nonroutable IPv4 addresses to one or more globally routable IPv4 addresses. For organizations using IPv6 addressing, there’s no need to translate IPv6 addresses to IPv6 addresses due to the abundance of IPv6 addresses.
NPTv6 translates the prefix portion of an IPv6 address but not the host portion or the application port numbers. The host portion is copied, and therefore remains the same on either side of the firewall. The host portion also remains visible within the packet header.
NPTv6 is supported on the following firewall models (NPTv6 with hardware lookup but packets go through the CPU):
  • PA-7000 Series firewalls
  • PA-5200 Series firewalls
  • PA-3200 Series firewalls
  • PA-800 firewall
  • PA-220 firewall

Unique Local Addresses

RFC 4193, Unique Local IPv6 Unicast Addresses, defines unique local addresses (ULAs), which are IPv6 unicast addresses. They can be considered IPv6 equivalents of the private IPv4 addresses identified in RFC 1918, Address Allocation for Private Internets, which can’t be routed globally.
A ULA is globally unique, but not expected to be globally routable. It’s intended for local communications and to be routable in a limited area such as a site, or among a small number of sites. Palo Alto Networks doesn’t recommend that you assign ULAs, but a firewall configured with NPTv6 will translate prefixes sent to it, including ULAs.

Reasons to Use IPv6

Although there’s no shortage of public, globally routable IPv6 addresses, there are reasons you might want to translate IPv6 addresses. It’s important to understand that NPTv6 doesn’t provide security. In general, stateless network address translation doesn’t provide any security; it provides an address translation function. NPTv6 doesn’t hide or translate port numbers. Set up firewall Security policies correctly in each direction to ensure that traffic is controlled as you intended.
  • Prevents asymmetrical routing—Asymmetric routing can occur if a Provider Independent address space (/48, for example) is advertised by multiple data centers to the global internet. By using NPTv6, you can advertise more specific routes from regional firewalls, and the return traffic will arrive at the same firewall where the source IP address was translated by the translator.
  • Provides address independence—You need not change the IPv6 prefixes used inside your local network if the global prefixes are changed (for example, by an ISP or as a result of merging organizations). Conversely, you can change the inside addresses at will without disrupting the addresses that are used to access services in the private network from the internet. In either case, you update a NAT rule rather than reassign network addresses.
  • Translates ULAs for routing—You can have
    Unique Local Addresses
    assigned within your private network, and have the firewall translate them to globally routable addresses. Thus, you have the convenience of private addressing and the functionality of translated, routable addresses.
  • Reduces explore to IPv6 prefixes—IPv6 prefixes are less exposed than if you didn’t translate network prefixes, however, NPTv6 isn’t a security measure. The interface identifier portion of each IPv6 address isn’t translated; it remains the same on each side of the firewall and visible to anyone who can see the packet header. Additionally, the prefixes aren’t secure; they can be determined by others.

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