saif1akbar,
You have a few options for what you are trying to accomplish. If all of the crypto endpoints are Cisco routers, you may want to go with GRE over IPsec. Here's a guide which discusses this and has some sample configuration. They guide incorrectly describes this as "IPsec over GRE" while in reality it is GRE over IPsec (IP traffic encapsulated in GRE, which is then encapsulated in ESP/IPsec): https://learningnetwork.cisco.com/docs/DOC-2457
If you are going to non-IOS devices or do not wish to use GRE over IPsec, you also have the option of crypto maps: http://www.cisco.com/c/en/us/td/docs/ios/sec_secure_connectivity/configuration/guide/15_0/sec_secure_connectivity_15_0_book/sec_cfg_vpn_ipsec.html#wp1089128
HTH,
Frank