Security of NAT devices under mobile and cable networks

• Main Authors: CHEN, HUNG-HUI, 陳紘暉
• Other Authors: CHEN,CHIEN-YUAN
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/74588b

碩士 === 國立高雄大學 === 資訊工程學系碩士班 === 105 === With the rapid development of 4G mobile networks and universal, there are a growing number of mobile devices connected to the Internet. Each Internet devices require IP addresses, but the existing IPv4 address is not enough for these network equipment and mobile devices use. Even though IPv6 can solve the problem of IP address shortage, not all network devices can use IPv6.Another solution to this problem is the Network Address Translation; NAT. On one hand, NAT mechanism solves the problem of lack of IPv4 network addresses, on the other hand allows web users a more convenient and safe environment, hence it is widely used by most people, so discussion of NAT network device security is an important issue. This paper discusses the security of mobile and cable networks NAT technology, and studies the NAT infrastructure, features (Filtering, Mapping), the general category (Full Cone NAT, Restricted Cone NAT, Port Restricted Cone NAT, Symmetric NAT) and technology (STUN, TURN, ICE), and proposed NAT security norms. Then for the current mobile network and cable network operators and commercially available NAT devices proceeds the security testing, and try to understand the level of security for these devices, and make safety recommendations for improvement.