User's Manual

29/OCT/2014 REVIEW DRAFT — CISCO CONFIDENTIAL
5-9
Cisco IR500 Series WPAN Gateway and Range Extender Installation and Configuration Guide
Chapter 5 Operation and Configuration
Information about Raw Socket Transport and MAP-T
Figure 5-6 MAP-T in a FAN and WPAN Gateway Scenario
RTUs
WPAN Range
Extender
CGR 1000
MAP-T Domain
MAP-T
Border Relay
ASR 1000
SCADA
Server
IP WAN
391927
WPAN
Gateways
There are defined IPv6 and IPv4 MAP-T prefixes inside the MAP-T domain enabling the NAT64
translation process to identify addresses to be translated, as well as get proper reachability and routing
through the MAP-T domain.
NAT44 is a component of the MAP solution, but the NAT44 in MAP differs from traditional NAT44
d
eploy
ments in that instead of assigning a public IPv4 address range to each field device for translation
(in the case of NAT), or a single public IPv4 address for translation (in the case of Port Address
Translation (PAT)) to each field device, it extends the granularity beyond a single public IPv4 address,
by being able to assign a port range to each of the field devices sharing the same IPv4 public address.
This unique address and port range combination is then translated into the IPv6 address space when
transitioning into the IPv6 domain using the MAP field device. The MAP algorithm still retains the
ability to assign the full IPv4 address or an IPv4 prefix to the MAP field device, but the WPAN gateway
only leverages the full IPv4 address to be allocated on a per WPAN gateway basis.
MAP-T Mapping Rules and Map Domain Parameters
Inside the MAP-T domain are defined IPv6 and IPv4 MAP-T prefixes enabling the NAT64 translation
process to identify addresses to be translated as well as get proper reachability and routing through the
MAP-T domain. Those are known as:
• MAP-T Default Mapping Rule (DMR): an IPv6 prefix used to address all destinations outside the
MAP-T domain.
– DMR IPv6 prefix and prefix length embeds any IPv4 addresses outside the MAP-T domain. For
example, within a MAP-T domain using a DMR IPv6 prefix = 2610:D0:1200:CAFE::/64, all
IPv4 translated packet sources and destinations outside the MAP-T domain have an IPv6
address based on this prefix, i.e. sending packets to IPv4 100.1.1.2 translated to IPv6
2610:d0:1200:cafe:64:101:200:0. The SCADA server IPv4 address is an example of a
destination outside of the MAP-T domain.
• MAP-T Basic Mapping Rule (BMR): the IPv6 and IPv4 prefixes used to address MAP-T nodes
inside the MAP-T domain
– BMR IPv4 prefix and prefix length are the IPv4 subnet selected to address all IPv4 nodes in a
MAP-T domain. For example, a MAP-T domain set-up with 153.10.10.0/24 as IPv4 subnet has
all IPv4 nodes configured with IPv4 address from this subnet, BMR IPv4 prefix = 153.10.10.0
and prefix length = 24