                        Proxy router mini HOWTO 0.92
                                    by
                               Delian Delchev


       1. What is proxy router?
       2. What is proxyrouted?
       3. Why proxy router?
       4. Where I can use proxyrouted?

 1. What is proxy router?
Proxy router is a router who send ARP replys for any computer that is on
another network connected to him. If any client send arp reqest for any
computer and this computer is on another physical network connected to
proxy router then proxy router send arp reply. Clent think that router
is computer for who hi search and send packets to router. Router resend
packets to computer. Because proxy router mascuarde self like computer
for who you search,It is very closer to bridge and clients not need to
have his IP in their routing tables.Proxy router is between router and
bridge.
 2. What is proxyrouted?
proxyrouted is a little program that make proxy router from linux box.
It is available from
  ftp://ftp.wfpa.acad.bg/pub/opersys/linux/delian/proxyrouted
 3. Why proxy router?
Proxy router is faster than bridge. That is because proxyrouted send only
arp replys,and not route packets. Linux kernel route packets and that is
faster.
You may use proxyrouted to implement any advanced things like this:
Large single network with routing. You may use network and broadcast address
and give it to clients. You may make anything like virtual network with
serial link.
 4. Where I can use proxyrouted?
You may make simple internet virtual network with proxyrouted.
If you have network like this:

+------Ethernet--------+       +------Ethernet--------+
|                      |  PPP  |                      |
|  PC1------------PC2--------------PC3----------PC4   |
|                      |       |                      |
+----------------------+       +----------------------+

PC1 - Eth. IP 192.168.1.1
PC2 - Eth. IP 192.168.1.2, PPP. IP 192.168.1.3
PC3 - PPP. IP 192.168.1.4, Eth. IP 192.168.1.5
PC4 - Eth. IP 192.168.1.6
You may make that PC4 and PC1 will be look like they are in one ethernet
(virtual) network.
You only need to start on PC2 and PC3 proxyrouted and setup anything like
this: (in routing tables)
PC1 - 192.168.1.0/255.255.255.0 on dev eth0 (ot anything else)
PC4 - 192.168.1.0/255.255.255.0 on dev eth0
PC2 - 192.168.1.0/255.255.255.0 on dev eth0,
      192.168.1.5/255.255.255.255 on dev ppp0,
      192.168.1.6/255.255.255.255 on dev ppp0
PC3 - 192.168.1.0/255.255.255.0 on dev ppp0,
      192.168.1.6/255.255.255.255 on dev eth0
Only routers (PC2 & PC3) need to know all and correct routing table, PC1 and
PC4 and anything else pc on the net (may be PC5,PC6 and ...) will be think
like they are in one big ethernet network.


  This document is not completed , pleace check for newest at:
  ftp://ftp.wfpa.acad.bg:/pub/opersys/linux/delian/proxyrouted