CN109560860B

CN109560860B - Satellite communication routing method and system

Info

Publication number: CN109560860B
Application number: CN201811579578.1A
Authority: CN
Inventors: 杨峰; 任维佳; 杜志贵; 向晓霞
Original assignee: Changsha Tianyi Space Technology Research Institute Co Ltd
Current assignee: Changsha Tianyi Space Technology Research Institute Co Ltd
Priority date: 2018-12-25
Filing date: 2018-12-25
Publication date: 2021-02-09
Anticipated expiration: 2038-12-25
Also published as: CN109560860A

Abstract

The invention relates to a satellite communication routing method and a satellite communication routing system, wherein the method comprises the following steps: storing routing information at the first satellite, the routing information determining possible destinations that can be routed from the first satellite within the satellite communications network and defining a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite to the possible destinations over one or more satellites and inter-satellite links; receiving at the first satellite an indication of a problem affecting a particular inter-satellite link between the second and third satellites, the problem comprising a real problem and/or a pseudo problem; updating routing information in response to the received indication to associate a routing path that includes the particular inter-satellite link with information that reflects a problem affecting the particular inter-satellite link; a particular routing path for routing data from the first satellite to a particular destination is selected from the set of routing paths based on the correlation and the data is transmitted along at least a portion of the selected particular routing path. The invention can route data more efficiently.

Description

Satellite communication routing method and system

Technical Field

The present invention relates to the field of telecommunication technologies, and in particular, to a satellite communication routing method and system.

Background

A satellite-based communication network may include a plurality of gateways and a plurality of satellites to relay communication signals between the gateways and a plurality of user terminals. A gateway is a ground station having an antenna for transmitting and receiving signals to and from a communication satellite. The gateway uses satellites to provide communication links for connecting user terminals to other user terminals or users of other communication systems such as the public switched telephone network, the internet, various public and/or private networks, and the like. Satellites are orbital receivers and repeaters used to relay information.

For satellite communication, due to limited communication resources, how to establish a routing path capable of efficient transmission for data in a satellite communication network is very important. For example, chinese patent publication No. CN108270478A discloses a method and an apparatus for establishing a satellite route, including: and acquiring network dynamic parameter information of each satellite node in the satellite network. And determining the construction cost of each routing path which is possibly passed from the source satellite node to the destination satellite node according to the network dynamic parameter information of each satellite node. And taking the routing path with the minimum construction cost as the actual routing path from the source satellite node to the destination satellite node. In the application, the construction cost of each routing path which is probably passed from a source satellite node to a target satellite node is determined according to the network dynamic parameter information of each satellite node, so that the routing path with the minimum construction cost is used as an actual routing path, the dynamic change of the satellite network can be fully considered in the routing construction of the satellite network, and the efficient and low-cost dynamic routing path is constructed. However, the routing path can be selected only according to the actual parameters of each satellite node, and the selection and division of the routing path are still not efficient.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a satellite communication routing method and a satellite communication routing system.

According to a preferred embodiment, a satellite communications routing method is applied in a satellite communications network comprising a plurality of satellites, wherein each satellite is configured to establish one or more inter-satellite links for wireless communications with one or more respective other satellites of the plurality of satellites to transmit data, the method comprising: storing routing information at the first satellite, the routing information determining possible destinations that can be routed from the first satellite within the satellite communications network and defining a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite to the possible destinations over one or more satellites and one or more corresponding inter-satellite links; receiving, at a first satellite, an indication of a problem affecting a particular inter-satellite link between a second satellite and a third satellite, wherein the problem comprises a real problem and/or a pseudo problem; updating routing information in response to receiving an indication of a problem affecting a particular inter-satellite link to associate a routing path defined in the routing information that includes the particular inter-satellite link with information reflecting the problem affecting the particular inter-satellite link; receiving at the first satellite data to be transmitted from the first satellite to a particular one of the possible destinations within the satellite communications network; in response to receiving data to be transmitted from a first satellite to a particular destination, accessing updated routing information, identifying a set of routing paths defined in the routing information for use from the first satellite to the particular destination in the accessed updated routing information, analyzing an association of each routing path comprising the set of routing paths with information having a characteristic reflecting a problem affecting a particular inter-satellite link, selecting a particular routing path from the set of routing paths for routing data from the first satellite to the particular destination based on the association, and transmitting data from the first satellite along at least a portion of the selected particular routing path.

According to a preferred embodiment, selecting a particular routing path from the set of routing paths for routing data from the first satellite to a particular destination based on the correlation includes: selecting a specific routing path for routing data from the first satellite to a specific destination from routing paths having no information associated therewith reflecting a problem affecting a specific inter-satellite link according to the association; and/or selecting a particular routing path from the portion of routing paths for routing data from the first satellite to the particular destination based on the association if the portion of routing paths is associated with information reflecting a problem affecting the particular inter-satellite link.

According to a preferred embodiment, receiving at a first satellite an indication of a problem affecting a particular inter-satellite link between a second satellite and a third satellite comprises receiving at the first satellite an indication that the particular inter-satellite link between the second satellite and the third satellite is congested, that there is a failure, or that data cannot currently be transmitted.

According to a preferred embodiment, the method further comprises: receiving at the first satellite different data to be transmitted from the first satellite to a particular destination; determining a first priority for data to be transmitted from a first satellite to a particular destination, selecting a different routing path from the set of routing paths for routing data having the first priority from the first satellite to the particular destination in response to the determined first priority, the different routing path not being associated with information reflecting that there is currently congestion for a particular inter-satellite link between the second satellite and the third satellite, transmitting data having the first priority from the first satellite along at least a portion of the selected different routing path; and determining a second priority for data to be transmitted from the first satellite to the particular destination, wherein the second priority is higher than the first priority, selecting a particular routing path for routing the data having the second priority from the first satellite to the particular destination from routing paths associated with information reflecting a current presence of congestion of a particular inter-satellite link between the second satellite and the third satellite based on the determined second priority for the data having the second priority, transmitting the data having the second priority along at least a portion of the selected particular routing path for routing the data having the second priority from the first satellite to the particular destination.

According to a preferred embodiment, the method comprises the step of assigning to the legacy data, which is transmitted via a specific inter-satellite link between the second satellite and the third satellite before implementation of selection of a specific routing path for routing the data with the second priority from the first satellite to a specific destination, from among routing paths associated with information reflecting the current presence of congestion of the specific inter-satellite link between the second satellite and the third satellite based on the determined second priority, and which has not yet completed transmission after implementation of selection, the right to continue transmission using the specific inter-satellite link between the second satellite and the third satellite at least until transmission of the legacy data is completed, but selectively reducing the rate of transmission of remaining packets of the legacy data based on a remaining transmission time calculated from transmission of the remaining packets of the legacy data at the original rate.

According to a preferred embodiment, selecting a particular routing path from the set of routing paths for routing data from the first satellite to a particular destination comprises: identifying a preferred routing path from the set of routing paths for routing data from the first satellite to a particular destination; determining that a preferred routing path for routing data from a first satellite to a particular destination is associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite and the third satellite; determining that the data corresponds to a pre-existing connection on a particular inter-satellite link; in response to determining that the preferred routing path for routing data from the first satellite to the particular destination is associated with information reflecting that the particular inter-satellite link between the second satellite and the third satellite is currently congested and that the determined data corresponds to a pre-existing connection on the particular inter-satellite link, selecting the preferred routing path as the particular routing path for routing data from the first satellite to the particular destination even if the preferred routing path is associated with information reflecting that the particular inter-satellite link between the second satellite and the third satellite is currently congested.

According to a preferred embodiment, the method comprises: receiving at the first satellite different data to be transmitted from the first satellite to a particular destination; identifying a preferred routing path from the set of routing paths for routing data from the first satellite to a particular destination; determining that a preferred routing path for routing data from a first satellite to a particular destination is associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite and the third satellite; determining that the different data does not correspond to a pre-existing connection on the particular inter-satellite link; in response to determining that the preferred routing path for routing data from the first satellite to the particular destination is associated with information reflecting a current presence of congestion of the particular inter-satellite link between the second satellite and the third satellite and that the different data does not correspond to a pre-existing connection on the particular inter-satellite link, selecting a candidate routing path from the set of routing paths for routing the different data from the first satellite to the particular destination, the candidate routing path being different from the preferred routing path and not associated with information reflecting a current presence of congestion of the particular inter-satellite link between the second satellite and the third satellite, transmitting the different data from the first satellite along at least a portion of the selected candidate routing path.

According to a preferred embodiment, the method further comprises: after transmitting the data, receiving, by the first satellite, a new indication that a problem affecting a particular inter-satellite link between the second satellite and the third satellite has been resolved; and in response to receiving a new indication that a problem affecting a particular inter-satellite link between the second satellite and the third satellite has been resolved, updating the routing information to disassociate a routing path of the particular inter-satellite link from information in the routing information that reflects the problem affecting the particular inter-satellite link.

According to a preferred embodiment, a satellite communications routing system includes a satellite communications network of satellites, each satellite configured to establish one or more inter-satellite links for wireless communications with one or more respective other satellites of a plurality of satellites to transmit data; storing routing information at the first satellite, the routing information determining possible destinations that can be routed from the first satellite within the satellite communications network and defining a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite to the possible destinations over one or more satellites and one or more corresponding inter-satellite links; receiving, at a first satellite, an indication of a problem affecting a particular inter-satellite link between a second satellite and a third satellite; updating routing information in response to receiving an indication of a problem affecting a particular inter-satellite link to associate a routing path defined in the routing information that includes the particular inter-satellite link with information reflecting the problem affecting the particular inter-satellite link; receiving at the first satellite data to be transmitted from the first satellite to a particular one of the possible destinations within the satellite communications network; in response to receiving data to be transmitted from a first satellite to a particular destination, accessing updated routing information, identifying a set of routing paths defined in the routing information for use from the first satellite to the particular destination in the accessed updated routing information, analyzing an association of each routing path comprising the set of routing paths with information having a characteristic reflecting a problem affecting a particular inter-satellite link, selecting a particular routing path from the set of routing paths for routing data from the first satellite to the particular destination based on the association, and transmitting data from the first satellite along at least a portion of the selected particular routing path.

Drawings

Fig. 1 is a simplified schematic diagram of a preferred embodiment of the present invention.

List of reference numerals

110: the first satellite 120: the second satellite 130: third satellite

140: the fourth satellite 150: the fifth satellite 160: sixth satellite

170: the seventh satellite 180: eighth satellite 200: ground station

300: user terminal

Detailed Description

The following detailed description is made with reference to the accompanying drawings.

In the description of the present invention, it is to be understood that the terms "first", "second", and the like, if any, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit indication of the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, the term "plurality", if any, means two or more unless specifically limited otherwise.

Example 1

The present embodiments disclose a satellite communications routing method that may be implemented by the system of the present invention and/or other alternative components. For example, the method of the present invention may be implemented using various components of the system of the present invention.

According to a preferred embodiment, a satellite communication routing method is applicable in a satellite communication network comprising a plurality of satellites, wherein each satellite is configured to establish one or more inter-satellite links for wireless communication with one or more respective other satellites of the plurality of satellites to transmit data. The method can comprise the following steps: routing information is stored at the first satellite 110 that determines possible destinations that can be routed from the first satellite 110 within the satellite communications network and defines a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite 110 to the possible destinations over one or more satellites and one or more corresponding inter-satellite links. The method can comprise the following steps: an indication of a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130 is received at the first satellite 110. The method can comprise the following steps: the routing information is updated in response to receiving an indication of a problem affecting a particular inter-satellite link to associate a routing path defined in the routing information that includes the particular inter-satellite link with information reflecting the problem affecting the particular inter-satellite link. The method can comprise the following steps: data to be transmitted from the first satellite 110 to a particular one of the possible destinations within the satellite communications network is received at the first satellite 110. The method can comprise the following steps: the updated routing information is accessed in response to receiving data to be transmitted from the first satellite 110 to a particular destination. The method can comprise the following steps: a set of routing paths defined in the routing information for use from the first satellite 110 to a particular destination is identified in the accessed updated routing information. The method can comprise the following steps: each routing path that makes up the set of routing paths is analyzed for associations with information that reflects problems affecting particular inter-satellite links. The method can comprise the following steps: a particular routing path for routing data from the first satellite 110 to a particular destination is selected from the set of routing paths based on the correlation. The method can comprise the following steps: data is transmitted from the first satellite 110 along at least a portion of the selected particular routing path. Preferably, the possible destination may be at least one of a downlink satellite, a ground station 200, and a user terminal 300.

According to a preferred embodiment, selecting a particular routing path from the set of routing paths for routing data from the first satellite 110 to a particular destination based on the correlation may include selecting a particular routing path for routing data from the first satellite 110 to a particular destination based on the correlation from routing paths that do not have information associated therewith that reflects a problem affecting a particular inter-satellite link. Preferably, the problem in the first satellite receiving the indication of the problem affecting the particular inter-satellite link between the second satellite and the third satellite may comprise a real problem and/or a pseudo problem. A real problem may be a problem that actually exists in the satellite communication network, such as a real congestion or a real failure. A pseudoproblem may be a problem that does not actually exist in the satellite communication network, such as pseudocongestion or a pseudofault, generated by a portion of the satellites in order to occupy more or dedicate a portion of a particular inter-satellite link. The invention can at least realize the following beneficial technical effects by adopting the mode: firstly, the situation that a special purpose or more occupation of some inter-satellite links is needed is converted into a pseudo problem mode which coexists with a real problem, and the reconstruction difficulty and the cost are lower for a built satellite communication network with less protocol change; second, other satellites receive the pseudoproblem and reduce or fail to transmit data from the particular inter-satellite link in question, thereby allowing other satellites capable of identifying the pseudoproblem to efficiently transmit data over the particular inter-satellite link.

According to a preferred embodiment, selecting a particular routing path from the set of routing paths for routing data from the first satellite 110 to a particular destination based on the correlation may include selecting a particular routing path from the set of routing paths that is not via a particular inter-satellite link based on the correlation for routing data from the first satellite 110 to the particular destination.

According to a preferred embodiment, selecting a particular routing path for routing data from the first satellite 110 to a particular destination based on the association may include selecting a particular routing path from a portion of the routing paths for routing data from the first satellite 110 to a particular destination based on the association if the portion of the routing paths is associated with information reflecting a problem affecting a particular inter-satellite link.

According to a preferred embodiment, receiving at the first satellite 110 an indication of a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130 may include receiving at the first satellite 110 an indication that a particular inter-satellite link between the second satellite 120 and the third satellite 130 is down.

According to a preferred embodiment, updating the routing information to associate the routing path defined in the routing information that includes the particular inter-satellite link with information reflecting a problem affecting the particular inter-satellite link may include associating the routing path defined in the routing information that includes the particular inter-satellite link with information reflecting a failure of the particular inter-satellite link between the second satellite 120 and the third satellite 130.

According to a preferred embodiment, receiving at the first satellite 110 an indication of a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130 may include receiving at the first satellite 110 an indication that the particular inter-satellite link between the second satellite 120 and the third satellite 130 is currently unable to transmit data.

According to a preferred embodiment, receiving at the first satellite 110 an indication of a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130 may include receiving at the first satellite 110 an indication of a current existence of congestion of the particular inter-satellite link between the second satellite 120 and the third satellite 130.

According to a preferred embodiment, updating the routing information to associate the routing path defined in the routing information that includes the particular inter-satellite link with information reflecting a problem affecting the particular inter-satellite link may include updating the routing information to associate the routing path defined in the routing information that includes the particular inter-satellite link with information reflecting that the particular inter-satellite link between the second satellite 120 and the third satellite 130 is currently congested.

According to a preferred embodiment, the method may comprise: different data to be transmitted from the first satellite 110 to a particular destination is received at the first satellite 110. The method can comprise the following steps: a first priority of data to be transmitted from the first satellite 110 to a particular destination is determined. The method can comprise the following steps: a different routing path for routing data from the first satellite 110 to a particular destination is selected from the set of routing paths in response to the determined first priority, the different routing path not being associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite 120 and the third satellite 130. The method can comprise the following steps: different data is transmitted from the first satellite 110 along at least a portion of the selected different routing path. The method can comprise the following steps: a second priority is determined for data to be transmitted from the first satellite 110 to a particular destination. The second priority is higher than the first priority. The method can comprise the following steps: a particular routing path for routing the data having the second priority from the first satellite 110 to a particular destination is selected for the data having the second priority from the routing paths associated with information reflecting the current presence of congestion of a particular inter-satellite link between the second satellite 120 and the third satellite 130 based on the determined second priority. Preferably, data transmitted via a particular inter-satellite link between the second satellite 120 and the third satellite 130 before implementation of selection of a particular routing path for routing the data having the second priority from the first satellite 110 to a particular destination is selected for the data having the second priority from among the routing paths associated with information reflecting that congestion currently exists for the particular inter-satellite link between the second satellite 120 and the third satellite 130 based on the determined second priority may continue to transmit the data using the particular inter-satellite link between the second satellite 120 and the third satellite 130 until transmission is complete, but the rate at which the data is transmitted may be selectively reduced based on a remaining transmission time condition at the original rate for remaining packets of data. For example, if the number of remaining packets is too large and may still need to be transmitted for 30s according to the original rate, the transmission rate is decreased to ensure the transmission of the data with the second priority. For another example, if the number of remaining packets is less and may need to be transmitted for 0.05s according to the original rate, the packets may be transmitted according to the original rate without decreasing the rate. The invention can at least realize the following beneficial technical effects by adopting the mode: the method actively associates part of inter-satellite links with congestion information for data with high priority and supplies the part of inter-satellite links with data with second priority, but different from dedicated links, the part of inter-satellite links can still be used by routing paths for transmitting other data, but due to the association of the congestion information, a satellite for transmitting other data can reduce the number of data packets sent to the part of inter-satellite links, so as to improve and guarantee the transmission efficiency of the data with the second priority.

According to a preferred embodiment, the information for the current presence of congestion in the data having the second priority from the routing path associated with information reflecting the current presence of congestion of the particular intersatellite link between the second satellite 120 and the third satellite 130 based on the determined second priority is information of pseudo-congestion established based on the indication of pseudo-congestion. The information of pseudo congestion may include a pseudo congestion level established according to the second priority. The level of pseudo-congestion may be set based on the total bandwidth of a particular inter-satellite link between the second satellite 120 and the third satellite 130, the currently occupied bandwidth, and the committed information rate for data having the second priority. The higher the pseudo congestion level, the greater the transmission rate limit on other current routing paths that use the second satellite 120 and the third satellite 130 to transmit data. Pseudocongestion in contrast to true congestion, pseudocongestion may refer to a satellite generating and sending out an indication of pseudocongestion and letting other satellites receiving the indication of pseudocongestion consider that congestion actually does not occur in the corresponding inter-satellite link, so that the satellite sending the indication of pseudocongestion or an associated satellite capable of identifying pseudocongestion can efficiently transmit data having the second priority using the corresponding inter-satellite link. While true congestion may refer to a phenomenon in which the number of packets reaching the corresponding satellite or inter-satellite link is too large to be handled in time by the corresponding satellite or inter-satellite link, thereby causing performance degradation of the corresponding satellite or inter-satellite link, and even the entire satellite communication network.

According to a preferred embodiment, the satellite generating the indication of pseudocongestion may send a first identification flag to a portion of the satellites within the satellite communications network to enable the portion of the satellites to identify the corresponding pseudocongestion based on the first identification flag while maintaining the original routing path and/or transmission rate. And the other part of the satellite in the satellite communication network which does not receive the first identification mark can not identify the corresponding pseudo congestion and can choose to change the original routing path and/or reduce the original transmission rate. Preferably, the satellite generating the indication of pseudo-congestion may randomly transmit the first identification flag to a portion of the satellites in the satellite communications network. Alternatively, the satellite generating the indication of the pseudo-congestion may preferably send the first identification flag to a specific part of the satellites according to a user setting. Alternatively, the satellite generating the indication of pseudocongestion may preferably select a part of the satellites having an importance exceeding the importance threshold according to the importance of each satellite in the satellite communication network and transmit the first identification flag to this part of the satellites. Preferably, the importance may be calculated using a weighting method based on node betweenness of the satellite, node precision, and node distance.

According to a preferred embodiment, the method may comprise: a third priority is determined for data transmitted from the first satellite 110 to the particular destination, wherein the third priority is higher than the second priority, and a particular routing path for routing the data having the third priority from the first satellite 110 to the particular destination is selected for the data having the third priority from among routing paths that are associated based on the determined third priority to reflect information that a particular inter-satellite link between the second satellite 120 and the third satellite 130 is currently faulty. Preferably, the information that a fault currently exists for the data having the third priority from the routing path associated with the information reflecting that a particular inter-satellite link between the second satellite 120 and the third satellite 130 currently has a fault based on the determined third priority may be a false fault. In the case of a false failure relative to a real failure, a false failure may refer to a failure occurring in a corresponding inter-satellite link, which is generated by one satellite and sent out an indication of a false failure, and let other satellites receiving the indication of the false failure consider that the corresponding inter-satellite link that has not actually failed has failed, so that the satellite sending the indication of the false failure or the associated satellite capable of identifying the false failure can exclusively transmit data with a third priority using the corresponding inter-satellite link. Preferably, the satellite generating the indication of the false failure may randomly transmit the second signature to a portion of the satellites in the satellite communications network. Alternatively, the satellite generating the indication of the false failure may preferably transmit the second signature to a particular portion of the satellites according to a user setting. Alternatively, the satellite generating the indication of the false failure may preferably select a part of the satellites having an importance degree exceeding the importance degree threshold according to the importance degree of each satellite in the satellite communication network and transmit the second identification flag to the part of the satellites. Preferably, the importance may be calculated using a weighting method based on node betweenness of the satellite, node precision, and node distance. A real failure may refer to a situation where the failure to reach the corresponding satellite results in failure to receive and/or transmit data, and the real failure may result in a breakdown of the corresponding satellite or inter-satellite link. The satellite generating the indication of the pseudofault transmits a second signature to at least a portion of the satellites within the satellite communications network to enable at least a portion of the satellites to identify the corresponding pseudofault based on the second signature. The invention can at least realize the following beneficial technical effects by adopting the mode: the dedicated channel is constructed for data having a higher priority than the second priority to better guarantee its transmission rate and efficiency.

According to a preferred embodiment, the first satellite 110 identifies a transmission status of data having a second priority, upon successful transmission of the data having the second priority to a particular destination via a particular routing path corresponding to the second priority, activates a first countdown timer having a first preset duration in response to the successful transmission, in the event that no other data having the second priority is received by the first satellite 110 for the first preset duration, the traffic bandwidth of the particular routing path corresponding to the second priority decreases as the first countdown timer time decreases and, when the first countdown timer time is zero, disassociates the routing path associated with information reflecting the current presence of congestion of the particular intersatellite link between the second satellite 120 and the third satellite 130 from the routing path associated with the information reflecting the current presence of congestion of the particular intersatellite link between the second satellite 120 and the third satellite 130 due to the data having the second priority and completely releases the association of the information reflecting the current presence of congestion of the particular intersatellite link between the second satellite 120 and the third satellite 130 corresponding to the second priority Determining the service bandwidth of a routing path; in the event that additional data having a second priority is received by the first satellite 110 within the first predetermined length of time, the additional data having the second priority is transmitted at least in part over the particular routing path corresponding to the second priority and the first countdown timer is reset to the default value. Preferably, in the event that the first satellite 110 receives additional data having the second priority for the first preset length of time, an attempt is made to restore the traffic bandwidth of the particular routing path corresponding to the second priority to the pre-reduction level. Preferably, in the event that an attempt is made to restore the traffic bandwidth of a particular routing path corresponding to the second priority to the pre-reduction level but part of the bandwidth is continuously occupied by data having the first priority for a time expected to exceed a second preset duration, the data having the first priority is at least partially discarded to restore the bandwidth of the routing path corresponding to the second priority to the pre-reduction level, and a notification is issued regarding the discarded data having the first priority. At least the following beneficial technical effects can be realized in the mode adopted by the invention: the bandwidth occupied by the data with the second priority can be gradually released based on the frequency degree of the data with the second priority, so that the problem that the service bandwidth of the related channel is released immediately after the data with the second priority is transmitted is solved, the subsequent frequent reconstruction is caused, and the problems that the related channel for transmitting the data with the second priority is always established, the service bandwidth cannot be allocated to other channels in idle time, the resource waste is caused, and the transmission capability cannot be effectively utilized are also solved.

According to a preferred embodiment, the first satellite 110 may identify a transmission status of data having the third priority. Upon successful transmission of data having a third priority to a particular destination over a particular routing path corresponding to the third priority, a second countdown timer having a third preset duration that is less than the first preset duration may be started in response to the successful transmission. In the event that no other data having a third priority is received by the first satellite 110 for the third preset length of time, the traffic bandwidth of the particular routing path corresponding to the third priority may be decreased as the second countdown timer time decreases and disassociated from the routing path associated with information reflecting the current presence of congestion of the particular inter-satellite link between the second satellite 120 and the third satellite 130 due to the data having the third priority and information reflecting the current presence of congestion of the particular inter-satellite link between the second satellite 120 and the third satellite 130 when the second countdown timer time is zero and completely free up the traffic bandwidth of the particular routing path corresponding to the third priority. In the event that additional data having a third priority is received by the first satellite 110 within the third predetermined length of time, the additional data having the third priority may be transmitted at least in part over the particular routing path corresponding to the third priority and the second countdown timer may be reset to the default value. Preferably, in the event that the first satellite 110 receives additional data having a third priority for the third predetermined length of time, an attempt is made to restore the traffic bandwidth of the particular routing path corresponding to the third priority to the pre-reduction level. Preferably, in the event that an attempt is made to restore the traffic bandwidth of the particular routing path corresponding to the third priority to the pre-reduction level but part of the bandwidth is continuously occupied by data having the first priority and/or the second priority and the duration of occupation is expected to exceed a fourth preset duration, the data having the first priority and/or the second priority is at least partially discarded to restore the bandwidth of the routing path corresponding to the third priority to the pre-reduction level, and a notification is issued regarding the discarded data having the first priority and/or the second priority. Preferably, the fourth preset duration is less than the second preset duration. Preferably, the data having the first priority is preferentially dropped and the data having the second priority is at least partially dropped to restore the bandwidth of the routing path corresponding to the third priority to the level before the reduction if dropping all of the data having the first priority transmitted on the particular routing path still fails to restore the bandwidth of the routing path corresponding to the third priority to the level before the reduction. The invention can at least realize the following beneficial technical effects by adopting the mode: firstly, the bandwidth occupied by the data with the third priority can be gradually released based on the frequency degree of the data with the third priority, so that the problem that the service bandwidth of a related channel is released immediately after the data with the third priority is transmitted is solved, the subsequent frequent reconstruction is caused, and the problems that the related channel for transmitting the data with the third priority is always established, the service bandwidth cannot be allocated to other channels when the related channel is idle, the resource waste is caused, and the transmission capability cannot be effectively utilized are also solved; secondly, since the specific routing path corresponding to the third priority is associated with the failure information and becomes the dedicated channel, since other satellites will stop using the portion of inter-satellite link to transmit data after receiving the indication of the failure of the portion of inter-satellite link, the set third predetermined duration is shorter than the second predetermined duration to release the dedicated channel more quickly after the corresponding data transmission is completed to reduce the influence on the data transmission of other satellites.

According to a preferred embodiment, the first satellite 110 can analyze the regularity of the distribution in time and in geographic space of the transmission frequency of the data with the second priority and/or of the data with the third priority. The first satellite can set a first preset time and a second preset time of different time and different geographic spaces respectively according to regularity.

According to a preferred embodiment, the method may comprise: different data to be transmitted from the first satellite 110 to a particular destination is received at the first satellite 110. The method can comprise the following steps: a preferred routing path for routing data from the first satellite 110 to a particular destination is identified from the set of routing paths. The method can comprise the following steps: determining a preferred routing path for routing data from the first satellite 110 to a particular destination is associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite 120 and the third satellite 130. The method can comprise the following steps: it is determined that the different data does not correspond to a pre-existing connection on a particular inter-satellite link. The method can comprise the following steps: in response to having determined that the preferred routing path for routing data from the first satellite 110 to the particular destination is associated with information reflecting that a particular inter-satellite link between the second satellite 120 and the third satellite 130 is currently congested and having determined that different data does not correspond to a pre-existing connection on the particular inter-satellite link, a candidate routing path for routing the different data from the first satellite 110 to the particular destination is selected from the set of routing paths. The candidate routing path may be different from the preferred routing path and not associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite 120 and the third satellite 130. Different data is transmitted from the first satellite 110 along at least a portion of the selected candidate routing path.

According to a preferred embodiment, the method may comprise: it is determined that the data corresponds to a pre-existing connection on a particular inter-satellite link. In response to having determined that the preferred routing path is identified as a preferred routing path for routing data from the first satellite 110 to the particular destination and that the determined data corresponds to a pre-existing connection on the particular inter-satellite link, the preferred routing path is selected as the particular routing path for routing data from the first satellite 110 to the particular destination even if the preferred routing path is associated with information reflecting that the particular inter-satellite link between the second satellite 120 and the third satellite 130 is currently congested. That is, the first satellite 110 receives the identification flag and thus has the ability to identify the pseudo problem, and selects the preferred path associated with the pseudo problem to efficiently transmit data. Preferably, at least two candidate routing paths for routing different data from the first satellite 110 to a particular destination are selected from the set of routing paths, and the at least two candidate routing paths may have a candidate ordering attribute that defines an order in which the candidate routing paths are to be used if the first satellite 110 receives an indication of a different problem.

According to a preferred embodiment, the method may comprise: identifying in the accessed updated routing information a set of routing paths defined in the routing information for use from the first satellite 110 to a particular destination includes identifying a preference order for the set of routing paths associated with information reflecting issues affecting a particular inter-satellite link. Selecting a particular routing path for routing data from the first satellite 110 to a particular destination may include: a routing path from the set of routing paths that is preferred over other routing paths in the set of routing paths is determined for routing transmissions from the first satellite 110 to the particular destination according to the preference order. A less preferred routing path is identified from the set of routing paths for routing data from the first satellite 110 to the particular destination according to the order of preference and without being associated with a sub-optimal routing path that reflects information that reflects a problem affecting the particular inter-satellite link, and the sub-optimal routing path may be selected as the particular routing path for routing data from the first satellite 110 to the particular destination if the preferred routing path is associated with information that reflects a problem affecting the particular inter-satellite link and the sub-optimal routing path is not associated with information that reflects a problem affecting the particular inter-satellite link.

According to a preferred embodiment, storing routing information on the first satellite 110 to define a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite 110 to the possible destinations over one or more satellites and one or more corresponding inter-satellite links may include: storing routing information at the first satellite 110 determines a plurality of different ordered lists of satellites for each determined possible destination to define a plurality of different corresponding routing paths for routing transmissions from the first satellite 110 to the possible destinations.

According to a preferred embodiment, storing routing information on the first satellite 110 to determine a plurality of different ordered lists of satellites for each determined possible destination to define a plurality of different corresponding routing paths for routing transmissions from the first satellite 110 to the possible destinations may include: at least two different ordered lists of satellites are stored, the at least two different ordered lists of satellites defining at least two different sets of routing paths from each other for routing transmissions from the first satellite 110 to a possible destination, and the different sets of the at least two sets of routing paths are not routed through any common satellite nodes other than the first satellite 110 and the possible destination.

According to a preferred embodiment, the method may comprise: after transmitting the data, receiving, by the first satellite 110, a new indication that a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130 has been resolved; in response to receiving a new indication that a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130 has been resolved, the routing information is updated to disassociate the routing path of the particular inter-satellite link from the information in the routing information that reflects the problem affecting the particular inter-satellite link.

According to a preferred embodiment, the method may comprise: the routing information is updated to reflect changes in the topology of the satellite communication network caused by the satellites orbiting.

According to a preferred embodiment, updating the routing information to associate routing paths defined in the routing information that include the particular inter-satellite link with information that reflects a problem affecting the particular inter-satellite link comprises updating the routing information to associate all routing paths defined in the routing information that include the particular inter-satellite link with information that reflects a problem affecting the particular inter-satellite link.

According to a preferred embodiment, the routing information stored by the first satellite 110 includes a routing table for determining possible destinations within the satellite communications network for data to be routed through the first satellite 110 and defining a plurality of different routing paths for each determined possible destination to enable routing of data from the first satellite 110 to the possible destinations over one or more satellites and one or more corresponding inter-satellite links; updating the routing information to associate the routing path defined in the routing information that includes the particular inter-satellite link with information that reflects a problem affecting the particular inter-satellite link includes updating the routing table to associate the routing path defined in the routing information that includes the particular inter-satellite link with information that reflects a problem affecting the particular inter-satellite link; accessing the updated routing information comprises accessing an updated routing table; identifying in the accessed updated routing information the set of routing paths defined in the routing information for going from the first satellite 110 to the particular destination includes identifying in the accessed updated routing table the set of routing paths defined in the routing table for going from the first satellite 110 to the particular destination.

According to a preferred embodiment, the data may be data packets such that receiving data from the first satellite 110 to be transmitted to a particular possible destination within the satellite communications network includes receiving data packets to be transmitted from the first satellite 110 to a particular possible destination within the satellite communications network. Selecting a particular routing path for routing data from the first satellite 110 to a particular destination includes selecting a particular routing path for routing data packets from the first satellite 110 to the particular destination. Transmitting data from the first satellite 110 along at least a portion of the selected particular routing path includes transmitting data packets from the first satellite 110 along at least a portion of the selected particular routing path.

According to a preferred embodiment, receiving at the first satellite 110 data to be transmitted from the first satellite 110 to a particular one of the possible destinations within the satellite communications network may include: data transmitted from the user terminal 300 to be transmitted from the first satellite 110 to a particular one of the possible destinations within the satellite communications network is received at the first satellite 110.

According to a preferred embodiment, receiving at the first satellite 110 data to be transmitted from the first satellite 110 to a particular one of the possible destinations within the satellite communications network may include receiving at the first satellite 110 data to be transmitted from the first satellite 110 to the ground station 200. Preferably, the communication connection between the satellite and the ground station 200 may be implemented in the K-band. The communication connection between the satellite and the user terminal 300 may be implemented in the L-band. The communication connection between the satellite and the satellite can be realized in the Ka band.

According to a preferred embodiment, receiving at the first satellite 110 data to be transmitted from the first satellite 110 to a particular one of the possible destinations within the satellite communications network may include receiving data to be transmitted from the first satellite 110 to another satellite.

According to a preferred embodiment, receiving at the first satellite 110 data to be transmitted from the first satellite 110 to a particular one of the possible destinations within the satellite communications network may include receiving data to be transmitted from the first satellite 110 to the user terminal 300. The user terminal 300 may be, for example, a terrestrial mobile satellite terminal.

According to a preferred embodiment, the method may comprise: detecting a problem affecting data transmission capability between a first satellite 110 and a second satellite 120 connected to each other via an inter-satellite link for wireless communication; distributing notifications of problems affecting data transmission capability between the first satellite 110 and the second satellite 120 to other satellites within the satellite communications network; the data routed in the satellite communications network involves making decisions based on the notifications when data is transmitted between the first satellite 110 and the second satellite 120.

Example 2

The embodiment also discloses a satellite communication routing method, in particular a routing path optimization method, which can be realized by the system and/or other alternative parts. For example, the method of the present invention may be implemented using various components of the system of the present invention. This embodiment may be a further improvement and/or a supplement to embodiment 1, and repeated contents are not described again. The preferred embodiments of the present invention are described in whole and/or in part in the context of other embodiments, which can supplement the present embodiment, without resulting in conflict or inconsistency.

According to a preferred embodiment, the method may comprise: storing routing information at the first satellite 110 that determines possible destinations that can be routed from the first satellite 110 within the satellite communications network and defines a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite 110 to the possible destinations over one or more satellites and one or more corresponding inter-satellite links; receiving at the first satellite 110 an indication of a problem affecting a particular inter-satellite link between the second satellite 120 and the third satellite 130, the indication comprising an indication of at least one of pseudocongestion, true congestion, a pseudofault, and a true fault existing at the particular inter-satellite link between the second satellite 120 and the third satellite 130; updating routing information to associate a routing path defined in the routing information that includes a particular inter-satellite link with a routing path that reflects at least one of pseudo congestion, real congestion, pseudo failure, and real failure that affects the particular inter-satellite link in response to receiving an indication of a problem that affects the particular inter-satellite link; a satellite in the satellite communications network generating an indication of pseudocongestion and/or pseudofault transmits an identification flag identifying the pseudocongestion and/or pseudofault to a portion of satellites in the satellite communications network such that the portion of satellites has the capability to identify the pseudocongestion and/or pseudofault; this portion of the satellite with the ability to identify pseudo-congestion and/or pseudo-faults is able to use the routing paths associated with pseudo-congestion and/or pseudo-faults, including particular inter-satellite links, in a manner that breaks through the congestion handling mechanisms and the fault handling mechanisms. Referring to fig. 1, fig. 1 shows a portion of satellites in a satellite communication network of a preferred embodiment, specifically including a first satellite 110, a second satellite 120, a third satellite 130, a fourth satellite 140, a fifth satellite 150, a sixth satellite 160, a seventh satellite 170, and an eighth satellite 180. Assume that the user terminal 300 is to transmit data to the ground station 200 through the first satellite 110, the second satellite 120, the third satellite 130, and the fourth satellite 140. The fifth satellite 150 generates an indication of pseudocongestion or pseudofailure of a particular inter-satellite link between the second satellite 120 and the third satellite 130 due to the transmission of high priority data and broadcasts to the other satellites and transmits identification flags identifying the pseudocongestion and/or pseudofailure to some of the satellites. If the first satellite 110 does not receive the identification flag, data may be transmitted from other satellite detours in the event that pseudocongestion cannot be identified, such as routing data to the ground station 200 using the routing paths of the first satellite 110, the sixth satellite 160, the seventh satellite 170, the eighth satellite 180, and the fourth satellite 140, or still routing data to the ground station 200 using the first satellite 110, the second satellite 120, the third satellite 130, and the fourth satellite 140 using a reduced speed transmission. If the first satellite 110 does not receive the identification flag, data can only be transmitted from other satellite detours without identifying the false failure, such as routing data to the ground station 200 using the routing paths of the first satellite 110, the sixth satellite 160, the seventh satellite 170, and the fourth satellite 140. However, if the first satellite 110 receives the identification flag, the congestion handling mechanism or the fault handling mechanism may be breached if a pseudocongestion or a pseudofault is identified, and data may still be transmitted to the ground station 200 via the first satellite 110, the second satellite 120, the third satellite 130, and the fourth satellite 140. And the first satellite may evaluate the effect of its data transmission on the data transmission of the fifth satellite and choose whether to down rate the transmission.

Example 3

The embodiment also discloses a satellite communication routing system, which is suitable for executing the steps of the method disclosed by the invention to achieve the expected technical effect. This embodiment may be a further improvement and/or a supplement to embodiments 1, 2 or a combination thereof, and repeated contents are not described again. The preferred embodiments of the present invention are described in whole and/or in part in the context of other embodiments, which can supplement the present embodiment, without resulting in conflict or inconsistency.

According to a preferred embodiment, a satellite communication routing system may include a satellite communication network of satellites. Each satellite may be configured to establish one or more inter-satellite links of wireless communication with one or more respective other satellites of the plurality of satellites to transmit data. The system may include at least a first satellite 110, a second satellite 120, and/or a third satellite 130. Preferably, the first satellite 110, the second satellite 120, and the third satellite 130 may each refer to any one of the satellites in the satellite communication network. A first satellite 110 in the system may obtain state information regarding inter-satellite links of a plurality of satellites in a satellite communications network. The state information may include a problem affecting a particular inter-satellite link between at least two satellites in the inter-satellite link. The first satellite 110 may obtain ephemeris data for each of one or more satellites of the satellite communication network. The first satellite 110 may determine a topology of the plurality of satellites based at least in part on the satellite ephemeris data. The system may obtain resource allocation information regarding network bandwidth resources of the inter-satellite links and a current allocation of network bandwidth resources to each inter-satellite link. The system may determine a plurality of routing paths between two satellites of a satellite communication network. Each routing path may include one or more inter-satellite links, and wherein each routing path is based at least in part on one or more of the information regarding inter-satellite link status.

According to a preferred embodiment, the first satellite 110 may obtain ephemeris data for each of one or more satellites of a satellite communication network. The first satellite 110 may determine a topology of a plurality of satellites in the satellite communications network based at least in part on the satellite ephemeris data.

The word "module" as used herein describes any type of hardware, software, or combination of hardware and software that is capable of performing the functions associated with the "module".

It should be noted that the above-mentioned embodiments are exemplary, and that those skilled in the art, having benefit of the present disclosure, may devise various arrangements that are within the scope of the present disclosure and that fall within the scope of the invention. It should be understood by those skilled in the art that the present specification and figures are illustrative only and are not limiting upon the claims. The scope of the invention is defined by the claims and their equivalents.

Claims

1. A satellite communications routing method for use in a satellite communications network comprising a plurality of satellites, wherein each satellite is configured to establish one or more inter-satellite links for wireless communications with one or more respective other satellites of the plurality of satellites to transmit data,

the method comprises the following steps:

storing routing information at the first satellite (110), the routing information determining possible destinations within the satellite communications network that can be routed from the first satellite (110) and defining a plurality of different routing paths for each determined possible destination to enable routing transmissions from the first satellite (110) to the possible destinations over one or more satellites and one or more corresponding inter-satellite links;

receiving, at the first satellite (110), an indication of a problem affecting a particular inter-satellite link between the second satellite (120) and the third satellite (130), wherein the problem comprises a real problem and/or a pseudo problem, wherein the real problem comprises a real congestion and/or a real failure and the pseudo problem comprises a pseudo congestion and/or a pseudo failure;

updating routing information in response to receiving an indication of a problem affecting a particular inter-satellite link to associate a routing path defined in the routing information that includes the particular inter-satellite link with information reflecting the problem affecting the particular inter-satellite link;

receiving at the first satellite (110) data to be transmitted from the first satellite (110) to a particular one of the possible destinations within the satellite communications network;

in response to receiving data to be transmitted from a first satellite (110) to a particular destination, accessing updated routing information, identifying a set of routing paths defined in the routing information for use from the first satellite (110) to the particular destination in the accessed updated routing information, analyzing an association of each routing path comprising the set of routing paths with information having a characteristic reflecting a problem affecting a particular inter-satellite link, selecting a particular routing path from the set of routing paths for use in routing data from the first satellite (110) to the particular destination based on the association, and transmitting data from the first satellite (110) along at least a portion of the selected particular routing path.

2. The method of claim 1, wherein selecting a particular routing path from the set of routing paths for routing data from the first satellite (110) to a particular destination based on the association comprises: selecting a particular routing path for routing data from the first satellite (110) to a particular destination from among routing paths that do not have information associated therewith that reflects a problem affecting a particular inter-satellite link, based on the association; and/or

A particular routing path for routing data from the first satellite (110) to a particular destination is still selected from the portion of routing paths based on the association if the portion of routing paths is associated with information reflecting a problem affecting the particular inter-satellite link.

3. The method of claim 2, wherein receiving at a first satellite (110) an indication of a problem affecting a particular inter-satellite link between a second satellite (120) and a third satellite (130) comprises receiving at the first satellite (110) an indication that the particular inter-satellite link between the second satellite (120) and the third satellite (130) is congested, that there is a failure, or that data is currently unavailable for transmission.

4. The method of claim 3, wherein the method further comprises: receiving at the first satellite (110) different data to be transmitted from the first satellite (110) to a particular destination;

determining a first priority for data to be transmitted from the first satellite (110) to a particular destination, selecting a different routing path from the set of routing paths for routing data having the first priority from the first satellite (110) to the particular destination in response to the determined first priority, the different routing path not being associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite (120) and the third satellite (130), transmitting the data having the first priority from the first satellite (110) along at least a portion of the selected different routing path; and

determining a second priority for data to be transmitted from the first satellite (110) to the particular destination, wherein the second priority is higher than the first priority, selecting a particular routing path for routing data having the second priority from the first satellite (110) to the particular destination from routing paths associated with information reflecting a current presence of congestion of a particular inter-satellite link between the second satellite (120) and the third satellite (130) based on the determined second priority for the data having the second priority, transmitting the data having the second priority along at least a portion of the selected particular routing path for routing data having the second priority from the first satellite (110) to the particular destination.

5. The method of claim 4, wherein in assigning the data having the second priority from the routing paths associated with information reflecting a current presence of congestion of a particular inter-satellite link between the second satellite (120) and the third satellite (130) based on the determined second priority, the data having the second priority is transmitted via a particular inter-satellite link between the second satellite (120) and the third satellite (130) prior to implementation of the selection of the particular routing path for routing the data having the second priority from the first satellite (110) to the particular destination, and the legacy data that has not completed transmission after the selection is made to be transmitted continues using the authority of the particular inter-satellite link transmission between the second satellite (120) and the third satellite (130) at least until the legacy data completes transmission, but selectively reduces the rate of transmitting the remaining packets of the legacy data according to the remaining transmission time calculated by transmitting the remaining packets of the legacy data at the original rate.

6. The method of claim 5, wherein selecting a particular routing path from the set of routing paths for routing data from the first satellite (110) to a particular destination comprises:

identifying a preferred routing path from the set of routing paths for routing data from the first satellite (110) to a particular destination;

determining that a preferred routing path for routing data from a first satellite (110) to a particular destination is associated with information reflecting that congestion currently exists for a particular inter-satellite link between the second satellite (120) and the third satellite (130);

determining that the data corresponds to a pre-existing connection on a particular inter-satellite link;

in response to having determined that the preferred routing path for routing data from the first satellite (110) to the particular destination is associated with information reflecting that the particular inter-satellite link between the second satellite (120) and the third satellite (130) is currently congested and having determined that the data corresponds to a pre-existing connection on the particular inter-satellite link, selecting the preferred routing path as the particular routing path for routing data from the first satellite (110) to the particular destination even if the preferred routing path is associated with information reflecting that the particular inter-satellite link between the second satellite (120) and the third satellite (130) is currently congested.

7. The method of claim 6, wherein the method comprises:

receiving at the first satellite (110) different data to be transmitted from the first satellite (110) to a particular destination;

determining that the different data does not correspond to a pre-existing connection on the particular inter-satellite link;

in response to determining that a preferred routing path for routing data from the first satellite (110) to a particular destination is associated with information reflecting that a particular inter-satellite link between the second satellite (120) and the third satellite (130) is currently congested and determining that different data does not correspond to a pre-existing connection on the particular inter-satellite link, selecting a candidate routing path from the set of routing paths for routing the different data from the first satellite (110) to the particular destination, the candidate routing path being different from the preferred routing path and not associated with information reflecting that the particular inter-satellite link between the second satellite (120) and the third satellite (130) is currently congested, transmitting the different data from the first satellite (110) along at least a portion of the selected candidate routing path.

8. The method of claim 7, wherein the method further comprises:

after transmitting the data, receiving, by the first satellite (110), a new indication that a problem affecting a particular inter-satellite link between the second satellite (120) and the third satellite (130) has been resolved; and

in response to receiving a new indication that a problem affecting a particular inter-satellite link between the second satellite (120) and the third satellite (130) has been resolved, the routing information is updated to disassociate a routing path of the particular inter-satellite link from information in the routing information that reflects the problem affecting the particular inter-satellite link.

9. A satellite communications routing system comprising a satellite communications network of a plurality of satellites, each satellite being configured to establish one or more inter-satellite links for wireless communications with one or more respective other satellites of the plurality of satellites to transmit data;

receiving, at the first satellite (110), an indication of a problem affecting a particular inter-satellite link between the second satellite (120) and the third satellite (130), wherein the problem comprises a real problem comprising real congestion and/or a real failure and/or a pseudo problem comprising pseudo congestion and/or a pseudo failure;

10. The system of claim 9, wherein selecting a particular routing path from the set of routing paths for routing data from the first satellite (110) to a particular destination based on the correlation comprises:

selecting a particular routing path for routing data from the first satellite (110) to a particular destination from among routing paths that do not have information associated therewith that reflects a problem affecting a particular inter-satellite link, based on the association; and/or