Here is a simple VoIP Lab in GNS3 environment. It is only used for my lab test and recorded here for future reference.

1. Topology:

  • GNS3 Topology:
  • Logic Topology:

xp(——–C3725 Router(

2. Enviroment:

    •  Router 3725 R1’s configuration in GNS3. Flash card is 32 96 MB to hold CME4.3 files.

3.  Basic Networking Setup 

  • @R1 : Show Version Information for C3725-AdventerpriseK9_IVS-M IOS, Version 12.4(15)T9.
  • @R1, Basic TCP configuration:

interface FastEthernet0/0
 ip address
 duplex auto
 speed auto

  • By default, telephony-service is not enabled: 

R1#show telephony-service
telephony-service is not enabled

  • Enable Telephony-Service by configure some commands under telephony-service.

4. Install CME on GNS3 3725 Router

  • Set up Environment:
    • C3725 Router ip is
    • XP Machine with TFTPD ip is
  • Copy cme-full- into C3725 Router. I tried another tftp server Pumpkin, but it gave me an error. FTP service should be faster than tftp. TFTP took 1 hour and 44 minutes to get whole package extracted. This lab is using tftp to make things simple. From C3725 router, run following three commands:

erase flash:
format flash:
archive tar /xtract tftp:// flash:

To be Continued:::




By Jon

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