# US 7,613,829 B2 · Proximity enforcement in heterogeneous network environments > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,613,829 B2 - Document ID: US7613829B2 - Status: Granted - Kind: B2 - Application number: 11/437,623 - Filed: 2006-05-22 - Published: 2007-11-22 - Granted: 2009-11-03 - Earliest claimed: 2006-05-22 - Assignees: Nokia Corporation - Inventors: Jukka Alve - Web page: https://patentgrep.com/patent/US7613829B2 ## CPC - H04L 63/10: {for controlling access to devices or network resources} - H04L 63/0492: {by using a location-limited connection, e.g. near-field communication or limited proximity of entities} - H04L 63/107: {wherein the security policies are location-dependent, e.g. entities privileges depend on current location or allowing specific operations only from locally connected terminals} - H04L 2463/101: applying security measures for digital rights management - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract The invention provides an enforcement mechanism for limiting the propagation of content to a predefined proximity in a heterogeneous network. The protection mechanism determines the distance associated with wireless links of the heterogeneous networks and verifies that the distance is within the predefined proximity limits. The distance may be measured by evaluating the signal strength of received signals. The protection mechanism further uses round trip time determinations to enforce the proximity limits on wired or unknown segments of the heterogeneous network. Specifically, the round trip time associated with a wired or unknown segment may be determined using the round trip time associated with the wireless segments and the total round trip time of the network as a whole. The round trip time of the wired or unknown segment is then compared to a round trip time limit associated with the proximity requirement for distributing content. ## Claims ### Claim 1 A method comprising: determining a distance of a first segment of a network established between a content source and a sink; determining whether the distance is within a predefined proximity threshold associated with the content propagation limitations; in response to determining that the distance is within the predefined proximity threshold, determining a first round trip time associated with the first segment; determining a total round trip time of the network between the content source and the sink; calculating a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; comparing the second round trip time with a round trip time threshold; and authorizing content propagation over the network in response to a determination that the second round trip time is lower than the predefined round trip time threshold. ### Claim 2 (depends on 1) The method of claim 1, wherein the second round trip time is further associated with a third segment of the network. ### Claim 3 (depends on 1) The method of claim 1, wherein the round trip time threshold is determined based on a predetermined round trip time budget and the first round trip time. ### Claim 4 (depends on 1) The method of claim 1, wherein the first segment includes a wireless link between the content source and an intermediate router. ### Claim 5 (depends on 4) The method of claim 4, wherein the wireless link is a short-range wireless connection. ### Claim 6 (depends on 4) The method of claim 4, wherein the distance of the first segment is determined based on a received power of a signal received by the content source. ### Claim 7 (depends on 1) The method of claim 1, further comprising preventing content propagation over the network in response to a determination that the second round trip time is higher than the predefined round trip time threshold. ### Claim 8 (depends on 1) The method of claim 1, wherein the second segment is a wired network connection. ### Claim 9 (depends on 1) The method of claim 1, further comprising: determining whether the total round trip time is less than the first round trip time; and in response to determining that the total round trip time is less than the first round trip time, preventing content propagation in the network. ### Claim 10 (depends on 1) The method of claim 1, wherein the content propagation limitations are based on a Digital Transmission Content Protection—Internet Protocol (DTCP-IP) protection system. ### Claim 11 (depends on 1) The method of claim 1, wherein the content propagation limitations are based on a Digital Video Broadcast—Content Protection and Copy Management system. ### Claim 12 A method comprising: determining a first round trip time associated with a first segment of a network established between a content source and a sink, wherein the first segment of the network is determined to meet a predefined proximity requirement based on a distance associated with the first segment, wherein the predefined proximity requirement is based on one or more content propagation limitations; determining a total round trip time of the network; calculating a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on the total round trip time and the first round trip time; comparing the second round trip time with a predefined round trip time threshold; and authorizing content propagation over the network in response to a determination that the second round trip time is lower than the predefined round trip time threshold. ### Claim 13 (depends on 12) The method of claim 12, wherein the first network segment is a short range wireless connection. ### Claim 14 (depends on 13) The method of claim 13, wherein the distance associated with the first network segment is determined based on a received power of a received signal. ### Claim 15 (depends on 12) The method of claim 12, wherein the first network segment is connected to an intermediate network device. ### Claim 16 (depends on 12) The method of claim 12, wherein the second round trip time is calculated based on a difference between the total round trip time and the first round trip time. ### Claim 17 (depends on 12) The method of claim 12, wherein authorization to transmit content through the network is further based on whether the total round trip time is greater than the first round trip time. ### Claim 18 (depends on 12) The method of claim 12, wherein the content propagation limitations are based on a Digital Transmission Content Protection—Internet Protocol (DTCP-IP) protection system. ### Claim 19 (depends on 12) The method of claim 12, wherein the content propagation limitations are based on a Digital Video Broadcast—Content Protection and Copy Management system. ### Claim 20 An apparatus comprising: a processor; and memory storing computer readable instructions that, when executed, cause the apparatus to: determine a distance associated with a trusted wireless segment of a network, wherein the trusted wireless segment connects the apparatus to an intermediate network device; determine whether the distance is within a predefined proximity threshold; in response to determining that the distance is within the predefined proximity threshold, determine a first round trip time associated with the wireless segment; determine a total round trip time of the network; calculate a second round trip time associated with at least an untrusted network segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; compare the second round trip time with a predefined round trip time limit; and authorize content propagation over the network in response to a determination that the second round trip time is lower than the predefined round trip time limit. ### Claim 21 (depends on 20) The apparatus of claim 20, wherein the trusted wireless segment includes a short-range wireless connection. ### Claim 22 (depends on 20) The apparatus of claim 20, wherein the distance of the trusted wireless segment is determined based on a received power of a signal received at the apparatus. ### Claim 23 (depends on 20) The apparatus of claim 20, wherein the computer readable instructions, when executed, further cause the apparatus to prevent content propagation over the network in response to a determination that the second round trip time is higher than the predefined round trip time threshold. ### Claim 24 (depends on 20) The apparatus of claim 20, wherein the computer readable instructions, when executed, further cause the apparatus to: determine whether the total round trip time is less than the first round trip time; and in response to determining that the total round trip time is less than the first round trip time, prevent content propagation in the network. ### Claim 25 (depends on 20) The apparatus of claim 20, wherein the network is a Digital Transmission Content Protection—Internet Protocol (DTCP-IP) network. ### Claim 26 An apparatus comprising: a processor; and memory storing computer readable instructions that, when executed, cause the apparatus to receive a selection of a content item for redistribution in a network; measure the distance associated with a trusted wireless segment of the network, wherein the measurement is made based on a received power of a signal received by the apparatus; transmit a first echo request to determine a first round trip time associated with the trusted wireless segment; transmit a second echo request to determine a total round trip time associated with the network; calculate a second round trip time associated with an untrusted segment of the network based on a difference between the total round trip time and the first round trip time; determine whether the second round trip time is below an allotted round trip time budget; and in response to determining that the second round trip time is below the allotted round trip time budget, authorize the selected content item to be transmitted through the network. ### Claim 27 A method comprising: receiving, at a content source, a first round trip time associated with a first network segment of a network established between the content source and a sink, wherein the first network segment is connected to at least the sink; determining a total round trip time of the network between the content source and the sink; calculating a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; comparing the second round trip time with a round trip time threshold; and authorizing content propagation over the network in response to determining that the second round trip time is less than the round trip time threshold. ### Claim 28 (depends on 27) The method of claim 27, wherein the first round trip time is determined by the sink. ### Claim 29 (depends on 27) The method of claim 27, further including determining, at the content source, a third round trip time associated with a third network segment, wherein the third network segment is connected to at least the content source. ### Claim 30 (depends on 29) The method of claim 29, wherein the calculation of the second round trip time is further based on the third round trip time. ### Claim 31 A method comprising: receiving, at a sink, a first round trip time associated with a first network segment of a network established between a content source and the sink, wherein the first network segment is connected to at least the content source; determining, at the sink, a total round trip time of the network between the content source and the sink; calculating a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; comparing the second round trip time with a round trip time threshold; and authorizing content propagation over the network in response to determining that the second round trip time is less than the round trip time threshold. ### Claim 32 (depends on 31) The method of claim 31, wherein the first round trip time is determined by the sink. ### Claim 33 (depends on 31) The method of claim 31, further including determining, at the sink, a third round trip time associated with a third network segment, wherein the third network segment is connected to at least the sink. ### Claim 34 (depends on 33) The method of claim 33, wherein the calculation of the second round trip time is further based on the third round trip time. ### Claim 35 One or more computer readable media storing computer readable instructions that, when executed, cause an apparatus to: determine a first round trip time associated with a first segment of a network established between a content source and a sink, wherein the first segment of the network is determined to meet a predefined proximity requirement based on a distance associated with the first segment, wherein the predefined proximity requirement is based on one or more content propagation limitations; determine a total round trip time of the network; calculate a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on the total round trip time and the first round trip time; compare the second round trip time with a predefined round trip time threshold; and authorize content propagation over the network in response to a determination that the second round trip time is lower than the predefined round trip time threshold. ### Claim 36 (depends on 35) The one or more computer readable media of claim 35, wherein the computer readable instructions, when executed, further cause the apparatus to prevent content propagation over the network in response to determining that the second round trip time is greater than the predefined round trip time threshold. ### Claim 37 An apparatus comprising: a processor; and memory storing computer readable instructions that, when executed, cause the apparatus to: determine a first round trip time associated with a first segment of a network established between a content source and a sink, wherein the first segment of the network is determined to meet a predefined proximity requirement based on a distance associated with the first segment, wherein the predefined proximity requirement is based on one or more content propagation limitations; determine a total round trip time of the network; calculate a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on the total round trip time and the first round trip time; compare the second round trip time with a predefined round trip time threshold; and authorize content propagation over the network in response to a determination that the second round trip time is lower than the predefined round trip time threshold. ### Claim 38 (depends on 37) The apparatus of claim 37, wherein the computer readable instructions, when executed, further cause the apparatus to prevent content propagation over the network in response to determining that the second round trip time is greater than the predefined round trip time threshold. ### Claim 39 (depends on 37) The apparatus of claim 37, wherein the first network segment is a short range wireless connection and wherein the distance associated with the first network segment is determined based on a received power of a received signal. ### Claim 40 One or more computer readable media storing computer readable instructions that, when executed, cause an apparatus to: receive, at a content source, a first round trip time associated with a first network segment of a network established between the content source and a sink, wherein the first network segment is connected to at least the sink; determine a total round trip time of the network between the content source and the sink; calculate a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; compare the second round trip time with a round trip time threshold; and authorize content propagation over the network in response to determining that the second round trip time is less than the round trip time threshold. ### Claim 41 (depends on 40) The one or more computer readable media of claim 40, wherein the second round trip time is calculated based on a difference between the total round trip time and the first round trip time. ### Claim 42 (depends on 40) The one or more computer readable media of claim 40, wherein the computer readable instructions, when executed, further cause the apparatus to prevent content propagation over the network in response to determining that the second round trip time is greater than the round trip time threshold. ### Claim 43 An apparatus comprising: a processor; and memory storing computer readable instructions that, when executed, cause the apparatus to: receive a first round trip time associated with a first network segment of a network established between a content source and a sink, wherein the first network segment is connected to at least the sink; determine a total round trip time of the network between the content source and the sink; calculate a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; compare the second round trip time with a round trip time threshold; and authorize content propagation over the network in response to determining that the second round trip time is less than the round trip time threshold. ### Claim 44 (depends on 43) The apparatus of claim 43, further comprising the content source, wherein the first round trip time is received at the content source. ### Claim 45 (depends on 43) The apparatus of claim 43, wherein the computer readable instructions, when executed, further cause the apparatus to prevent content propagation over the network in response to determining that the second round trip time is greater than the round trip time threshold. ### Claim 46 One or more computer readable media storing computer readable instructions that, when executed, cause an apparatus to: receive, at a sink, a first round trip time associated with a first network segment of a network established between a content source and the sink, wherein the first network segment is connected to at least the content source; determine, at the sink, a total round trip time of the network between the content source and the sink; calculate a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; compare the second round trip time with a round trip time threshold; and authorize content propagation over the network in response to determining that the second round trip time is less than the round trip time threshold. ### Claim 47 (depends on 46) The one or more computer readable media of claim 46, wherein the first round trip time is determined by the sink. ### Claim 48 (depends on 46) The one or more computer readable media of claim 46, wherein the computer readable instructions, when executed, further cause the apparatus to determine, at the sink, a third round trip time associated with a third network segment, wherein the third network segment is connected to at least the content source. ### Claim 49 An apparatus comprising: a processor; and memory storing computer readable instructions that, when executed, cause the apparatus to: receive a first round trip time associated with a first network segment of a network established between a content source and a sink, wherein the first network segment is connected to at least the content source; determine a total round trip time of the network between the content source and the sink; calculate a second round trip time associated with at least a second segment of the network, wherein the calculation is made based on a difference between the total round trip time and the first round trip time; compare the second round trip time with a round trip time threshold; and authorize content propagation over the network in response to determining that the second round trip time is less than the round trip time threshold. ### Claim 50 (depends on 49) The apparatus of claim 49, wherein the computer readable instructions, when executed, further cause the apparatus to determine, at the sink, a third round trip time associated with a third network segment, wherein the third network segment is connected to at least the content source. ### Claim 51 (depends on 49) The apparatus of claim 49, wherein the computer readable instructions, when executed, further cause the apparatus to prevent content propagation over the network in response to determining that the second round trip time is greater than the round trip time threshold.