Patent ID: 8484385

Claim:
A method comprising: receiving, by a network device, one or more packets from a client device; determining, by the network device and using particular information in the one or more packets, whether a first data structure stores an entry that includes information matching the particular information, the first data structure storing information identifying applications executed by client devices; identifying, by the network device and in the entry, information identifying a particular application being executed by the client device when the first data structure stores the entry that includes the information matching the particular information; comparing, by the network device, the particular information to information in a second data structure to identify the particular application being executed by the client device when the first data structure does not store the entry that includes the information matching the particular information, the second data structure storing signature information associated with one or more applications, comparing the particular information to the information in the second data structure including: searching for a pattern, in the second data structure, that matches a pattern in the one or more packets; and applying, by the network device, an access policy to determine whether to grant, to the client device, access to a resource in a network associated with the network device, the access policy being based on the particular application.