In a company my boss asked me to create data transaction between P.O.S and the credit server in the network.

P.O.S was connected to the telephone line, and the server connected to the LAN, but how could I make connection between 2 different media (telephone line and Ethernet)?

I used an external modem and ISR router 1841 as devices to achieve this request.

Here is the picture how I did:

As you see in the picture P.O.S was connected to the External modem and modem need special cable in order to connect to the Router (DB 9 to DB 25).on the other side of the network Server connected to the router through Ethernet switch. About IP addressing Server and P.O.S used 2 different class of address, in other word they must be in different network (subnet).now you know how to make physical connection. About configuring Router here are the commands that I used:

****** AUX port configuration*******

Router(config)#line aux 0

Router(config-line)#login local

Router(config-line)#modem inout

Router(config-line)#modem  autoconfigure  type  pol

Router(config-line)#transport input all

Router(config-line)#transport  output  none

***** Define Username and Password *****

Router(config)#username ***** password *****

// this username & password is the same as in the credit server was defined by programmer

******* Interface Confoguration******

Router(config)# int F0/0

Router(config-if)#ip  address  192.168.3.41    255.255.255.0

****** Async  configuration******

Router(config)#int  async 1

Router(config-if)#ip address 10.10.10.1    255.255.255.0

Router(config-if)# encapsulation ppp

Router(config-if)# async  mode  dedicated

Router(config-if)# peer  default  ip  address  pool  test

Router(config-if)# ppp  authentication  pap  chap

****** Assign IP to the P.O.S******

Router(config)#ip  local  pool  test 10.10.10.2   10.10.10.20

***** Routing to the Async ******

Router(config)# ip  route  0.0.0.0  0.0.0.0   Async 1