The proliferation of types of data creates difficulty for the traditional IP address, to handle such a large amount of data it should have to look up large routing tables. MPLS is a solution to solve such problem. MPLS is a tunneling protocol that handles any kind of layer 2 or layer 3 protocols that is the reason for its name “Multiprotocol Label switching”. In MPLS node, routing is done by attaching labels to incoming packets this solves looking up large routing tables which is the problem of the traditional IP network. MPLS security is viewed from the VPN point of view even if VPN is vulnerable to addition, deletion and modification of users’ data. In order to solve these security threats we proposed a cryptographic algorithm that provides confidentiality, integrity and source authentication. We used the convenience of public key encryption for key exchange and symmetric key fast encryption time. RSA public key encryption used for encrypting session keys and AES symmetric encryption used for encrypting user’s data and the general hash function to check the integrity of the data. We used experimental research methodology to achieve our objective. NS2.35 is used for simulation purpose as a tool and C++ and TCL for scripting language, while NS2 Visual Trace Analyzer 0.2.72 is used for analyzing the generated trace file. In the experiment we performed four encryptions to assess the RTT, encryption time, delay, decryption time and time to make hash value. In the simulation it takes 50ms RTT and with 0.01ms minimum and 0.026ms maximum encryption time and 0.001ms minimum and 0.01ms maximum time for hashing. The decryption takes 0.019ms minimum and 0.02ms maximum simulation time with 0.001ms hashing time. In the presence of UDP flooding attack in uniform 5kbps bottleneck bandwidth only the 50% packets reach to the destination.