create P4 basis + smaller updates

Signed-off-by: Nico Schottelius <nico@nico-notebook.schottelius.org>

doc/.gitignore

@@ -0,0 +1,9 @@
+*.pdf
+plan.tex
+*.aux
+*.glo
+*.lof
+*.log
+*.lot
+*.out
+*.toc

doc/plan.org

@@ -104,10 +104,22 @@ user@T:~# iptables  -t mangle -A PREROUTING \
 **** Cisco (?)
 *** P4 based implementation
     TBD
-**** Static mappings
-     - need table
-     - need tcp & udp translation
+**** General
+     - IPv6 subnet 2001:db8::/32
+     - IPv6 hosts are in 2001:db8:6::/64
+     - IPv6 default router (::/0) is 2001:db8:6::42/64
+     - IPv4 mapped Internet "NAT64 prefix" 2001:db8:4444::/96 (should
+       go into a table)
+     - IPv4 hosts are in 10.0.4.0/24
+     - IPv6 in IPv4 mapped hosts are in 10.0.6.0/24
+     - IPv4 default router = 10.0.0.42
 
+**** Static mappings
+      - likely need table(s)
+      - need tcp & udp translation
+***** Hosts
+****** Left side: IPv6
+****** Right side: IPv4
 **** Requirements
      -
 *** Performance comparison