# US 7,610,622 B2 · Supporting options in a communication session using a TCP cookie > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,610,622 B2 - Document ID: US7610622B2 - Status: Granted - Kind: B2 - Application number: 11/348,977 - Filed: 2006-02-06 - Published: 2007-08-09 - Granted: 2009-10-27 - Earliest claimed: 2006-02-06 - Assignees: Cisco Technology, Inc. - Inventors: Dan Touitou; Michael Zayats; Rajan Goyal - Web page: https://patentgrep.com/patent/US7610622B2 ## CPC - H04L 63/1458: {Denial of Service} - H04L 63/168: {above the transport layer} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A defender operable to support options in a communication session intercepts a connection request packet sent from a client to a server. The defender identifies a client option combination associated with the client from the connection request packet. The defender establishes a client option index corresponding to the client option combination, and encodes the client option index into a cookie of an acknowledgment packet. The defender then sends the acknowledgment packet to the client. ## Claims ### Claim 1 A method for supporting options in a communication session, comprising: intercepting a connection request packet sent from a client to a server, the connection request packet intercepted by a defender; identifying a client option combination of the client from the connection request packet, the client option combination comprising a set of one or more Transmission Control Protocol (TCP) parameters for communication with the client; establishing a client option index corresponding to the client option combination, the client option index configured to be encoded into a cookie to communicate the client option combination; encoding the client option index into a cookie of an acknowledgment packet in order to provide the client option index to the client; and sending the acknowledgment packet to provide to the client the client option index used to communicate the client option combination client in order to facilitate establishing a connection requested by the connection request packet. ### Claim 2 (depends on 1) The method of claim 1, wherein: the connection request packet comprises a SYN packet; and the acknowledgment packet comprises a SYN acknowledgment packet. ### Claim 3 (depends on 1) The method of claim 1, further comprising: establishing a server option combination corresponding to the client option combination, the server option combination associated with the server, the server option combination comprising a set of one or more parameters for communication with the server; and sending the established server option combination as a part of the acknowledgment packet. ### Claim 4 (depends on 1) The method of claim 1, further comprising determining a corresponding option combination by: sniffing a plurality of packets; establishing the client option combination in response to sniffing the plurality of packets; and establishing a server option combination corresponding to the client option combination in response to sniffing the plurality of packets, the server option combination comprising a set of one or more parameters for communication with the server. ### Claim 5 (depends on 1) The method of claim 1, further comprising generating a table comprising one or more corresponding option combinations by: sniffing a plurality of packets; establishing a plurality of corresponding option combinations in response to sniffing the plurality of packets, a corresponding option combination comprising an established client option combination and a corresponding established server option combination, the server option combination comprising a set of one or more parameters for communication with the server; and selecting a subset from the plurality of corresponding option combinations. ### Claim 6 (depends on 1) The method of claim 1, further comprising discovering a corresponding option combination by: allowing an allowable packet from the client to the server; establishing the client option combination from the allowable packet; allowing an allowable response packet from the server to the client; and establishing a server option combination corresponding to the client option combination from the allowable response packet, the server option combination comprising a set of one or more parameters for communication with the server. ### Claim 7 A defender operable to support options in a communication session, comprising: an interface operable to: intercept a connection request packet sent from a client to a server; and a processor coupled to the interface and operable to: identify a client option combination of the client from the connection request packet, the client option combination comprising a set of one or more Transmission Control Protocol (TCP) parameters for communication with the client; establish a client option index corresponding to the client option combination, the client option index configured to be encoded into a cookie to communicate the client option combination; encode the client option index into a cookie of an acknowledgment packet in order to provide the client option index to the client; and the interface further operable to: send the acknowledgment packet to provide to the client the client option index used to communicate the client option combination client in order to facilitate establishing a connection requested by the connection request packet. ### Claim 8 (depends on 7) The defender of claim 7, wherein: the connection request packet comprises a SYN packet; and the acknowledgment packet comprises a SYN acknowledgment packet. ### Claim 9 (depends on 7) The defender of claim 7, the processor further operable to: establish a server option combination corresponding to the client option combination, the server option combination associated with the server, the server option combination comprising a set of one or more parameters for communication with the server; and send the established server option combination as a part of the acknowledgment packet. ### Claim 10 (depends on 7) The defender of claim 7, the processor further operable to determine a corresponding option combination by: sniffing a plurality of packets; establishing the client option combination in response to sniffing the plurality of packets; and establishing a server option combination corresponding to the client option combination in response to sniffing the plurality of packets, the server option combination comprising a set of one or more parameters for communication with the server. ### Claim 11 (depends on 7) The defender of claim 7, the processor further operable to generate a table comprising one or more corresponding option combinations by: sniffing a plurality of packets; establishing a plurality of corresponding option combinations in response to sniffing the plurality of packets, a corresponding option combination comprising an established client option combination and a corresponding established server option combination, the server option combination comprising a set of one or more parameters for communication with the server; and selecting a subset from the plurality of corresponding option combinations. ### Claim 12 (depends on 7) The defender of claim 7, the processor further operable to discover a corresponding option combination by: allowing an allowable packet from the client to the server; establishing the client option combination from the allowable packet; allowing an allowable response packet from the server to the client; and establishing a server option combination corresponding to the client option combination from the allowable response packet, the server option combination comprising a set of one or more parameters for communication with the server. ### Claim 13 A defender operable to support options in a communication session, comprising: means for receiving a connection request packet from a client, the connection request packet directed to a server; means for identifying a client option combination of the client from the connection request packet, the client option combination comprising a set of one or more Transmission Control Protocol (TCP) parameters for communication with the client; means for establishing a client option index corresponding to the client option combination, the client option index configured to be encoded into a cookie to communicate the client option combination; means for encoding the client option index into a cookie of an acknowledgment packet in order to provide the client option index to the client; and means for sending the acknowledgment packet to provide to the client the client option index used to communicate the client option combination client in order to facilitate establishing a connection requested by the connection request packet.