WO2013160048A1

WO2013160048A1 - Dynamic allocation of network layer addresses

Info

Publication number: WO2013160048A1
Application number: PCT/EP2013/056338
Authority: WO
Inventors: Samuel JEYARAJ J; Brinda Lakshmi
Original assignee: Alcatel Lucent
Priority date: 2012-04-24
Filing date: 2013-03-26
Publication date: 2013-10-31

Abstract

A method for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices (104) connected to a mobile consumer premises equipment (CPE) (102) is described herein. In said implementation, the method includes initiating registration of available sub-network of NLAs for allocation to the client devices(104), based on one of receipt of a subnet response option in an offer message and transmission of a default subnet mask parameter in a mobile internet protocol (MIP)register request. A confirmation is received for allocation of the available sub-network of NLAs for the client devices (104). Further, available NLAs are allocated to the plurality of client devices (104), based on the available sub-network of NLAs.

Description

DYNAMIC ALLOCATION OF NETWORK LAYER ADDRESSES

FIELD OF INVENTION

[0001] The present subject matter relates to allocation of network layer addresses and, particularly but not exclusively, to dynamic allocation of network layer addresses to client devices connected to a mobile consumer premises equipment (CPE).

BACKGROUND

[0002] With an increased usage of technology in our day-to-day activities, providing ubiquitous connectivity is becoming an important unique-selling-point (USP) for various communication service providers (CSPs). As CSPs cater to a large number of users, the ability to control and monitor connections is of utmost importance for providing quality service to the user. Therefore, generally, large clusters of users connected over a network are broken down into small clusters, and the small clusters are then separately catered to. Further, for providing communication services, such as internet access, to a small cluster of users, a small sub-network is created, and connected to CSP's network through a consumer premises equipment (CPE). The CPE serves as an access gateway for allowing access of the CSP's network to the client devices of the sub-network and achieves routing of data between the sub-network and the CSP network.

[0003] Conventionally, for achieving connectivity of the sub-network with the CSP network, the CPE, such as a router or a switch operating at a network layer, say based on internet protocol (IP), is allocated a single public network layer address, such as a public IP address. The CPE in turn is configured to implement features, such as network layer address translation (NAT), to provide access of the network to the client devices. For this, the network layer addresses of the client devices in the sub-network are masked and made private. Consequently, the transfer of data between the sub-network and the CSP network is achieved based on the public network layer address of the CPE. From the CPE, incoming data is further directed to the appropriate client device in the sub-network. In addition, the CPE can be configured to provide connectivity services, between the CSP network and the sub-network, while in mobile mode, i.e., when location of the CPE is changing across various networks. In such a case also, the CPE routes all communication between the sub-network and the CSP network based on the public network layer address of the CPE. SUMMARY

[0004] This summary is provided to introduce concepts related to dynamic allocation of network layer addresses to client devices connected to a mobile consumer premises equipment (CPE). This summary is not intended to identify essential features of the claimed subject matter nor is it directed to use in determining or limiting the scope of the claimed subject matter.

[0005] According to an implementation, a method for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices connected to a mobile consumer premises equipment (CPE) is described herein. In said implementation, the method includes initiating registration of available sub-network of NLAs for allocation to the client devices, based on one of receipt of a subnet response option in an offer message and transmission of a default subnet mask parameter in a mobile internet protocol (MIP) register request. A confirmation is received for allocation of the available sub-network of NLAs for the client devices. Further, available NLAs are allocated to the plurality of client devices, based on the available sub-network of NLAs, for directly routing data between the plurality of client devices and one or more host devices.

[0006] According to another implementation, a mobile Consumer Premise Equipment (CPE) for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices supported by the mobile CPE, is described herein. In said implementation, the mobile CPE includes a processor and a memory coupled to the processor. The memory includes a registration module configured to transmit an MIP register request for achieving MIP registration of the mobile CPE. The MIP register request comprises a default subnet mask parameter indicative of a request for allocation of an available sub-network of NLAs for the plurality of client devices. Further, in response to the MIP register request, an MIP register response is obtained. The MIP register response includes a subnet mask parameter for determining the available sub-network of NLAs for allocation to the client devices. The MIP register response indicates association of the available sub-network of NLAs for allocation to the client devices with at least an NLA of a home agent catering to the mobile CPE.

[0007] According to yet another implementation, a mobile Consumer Premise Equipment (CPE) for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices supported by the mobile CPE, is described herein. In said implementation, the mobile CPE includes a processor and a memory coupled to the processor. The memory includes a registration module configured to transmit a discover message to at least one IP -based server, the discover message comprising a subnet request option indicative of a request to allocate an available subnetwork of NLAs for the plurality of client devices. In response to the discover message, an offer message is obtained from the at least one IP -based server. The offer message can include a subnet response option indicating availability of the NLAs for allocation to the plurality of client devices and a subnet mask parameter for determining the available sub-network of NLAs for allocation the client devices. The registration module is further configured to provide a request message for registration of the available sub-network of NLAs, in response to the offer message.

[0008] According to yet another implementation, a proxy mobile internet protocol (PMIP) client for achieving dynamic allocation of network layer addresses (NLAs) to a plurality of client devices connected to a mobile consumer premises equipment (CPE), is described herein. In said implementation, the PMIP client is configured to transmit an MIP register request for achieving the MIP registration, the transmission being triggered by the mobile CPE. The MIP register request can include an available sub-network of NLAs for allocation to the client devices determined based on a subnet response option. Further, in response to the MIP register request, an MIP register response is obtained. The MIP register response is indicative of association of available NLAs for allocation to the client devices, determined based on the available subnetwork of NLAs, with at least an NLA of a home agent.

[0009] According to yet another implementation, an IP -based server for facilitating dynamic allocation of a network layer address (NLA) to each of a plurality of client devices connected to a mobile CPE, is described herein. In said implementation, the IP -based server is configured to receive a discover message from the mobile CPE, the discover message including a subnet request option indicating a request to allocate a sub-network of NLAs for the plurality of client devices. Based on the discover message, the IP -based server can transmit an offer message to the mobile CPE, the offer message comprising a subnet response option indicating availability of the sub-network of NLAs for allocation to the plurality of client devices. The offer message further includes a subnet mask parameter for determining the sub-network of NLAs for allocation the client devices.

[0010] According to yet another implementation, a home agent for facilitating dynamic allocation of a network layer address (NLA) to each of a plurality of client devices connected to a mobile CPE, is described herein. In said implementation, the home agent is configured to receive a mobile internet protocol (MIP) register request for MIP registration. In response to the MIP register request, the home agent can perform the MIP registration. In addition, the home agent can transmit, based on the MIP register request, an MIP register response confirming the MIP registration of available sub-network of NLAs for allocation to the client devices.

[0011] According to yet another implementation, a computer-readable medium having embodied thereon a computer program for executing a method for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices connected to a mobile consumer premises equipment (CPE). In said implementation, the method includes initiating mobile internet protocol (MIP) registration of the mobile CPE, based on one of receipt of a subnet response option and receipt of an agent advertisement. In response to the MIP register request, an MIP register response is received, the MIP register response including a subnet mask parameter for determining an available sub-network of NLAs for allocation to the plurality of client devices. The MIP register response can indicate registration of the available sub-network of NLAs for allocation to the plurality of client devices.

BRIEF DESCRIPTION OF THE FIGURES

[0012] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system and/or methods in accordance with embodiments of the present subject matter are now described, by way of example only, and with reference to the accompanying figures, in which:

[0013] Figure 1 illustrates a network implementation of a mobile consumer premises equipment (CPE) for dynamic allocation of network layer addresses to client devices connected to the mobile consumer premises equipment (CPE), according to an embodiment of the present subject matter.

[0014] Figure 2 illustrates a data flow diagram indicating dynamic allocation of network layer addresses to the client devices connected to the mobile CPE, according to an implementation of the present subject matter. [0015] Figure 3 illustrates a data flow diagram indicating dynamic allocation of network layer addresses to the client devices connected to the mobile CPE, according to another implementation of the present subject matter.

[0016] Figure 4 illustrates a method for dynamic allocation of network layer addresses to the client devices connected to the mobile CPE, according to an implementation of the present subject matter.

[0017] Figure 5 illustrates a method for dynamic allocation of network layer addresses to the client devices connected to the mobile CPE, according to another implementation of the present subject matter.

[0018] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown. DESCRIPTION OF EMBODIMENTS

[0019] Conventionally, for providing connectivity and regulating quality of connectivity to various users, communication service providers (CSP) segregate large network having large clusters of users into various sub-networks, each having small clusters of users, and provide connection services to the small clusters of users in the sub-networks. The connectivity between a CSP network and a sub-network is achieved through consumer premises equipment (CPE), such as a device operating at network layer, say based on internet protocol (IP). Further, in an example, for providing connection services to client devices in the sub-network, the CPE is allocated a public internet protocol (IP) address by the CSP and the CPE further allocates IP addresses to each of the client devices in the sub-network. [0020] Further, the CPE implements features, such as network address translation (NAT) and firewall, to facilitate secure connectivity between the CSP network and the sub-network. As a result of the implementation of such features, the IP addresses allocated to the client devices are masked and made private to devices outside the sub-network. Hence, the transfer of data between the CSP network and the sub-network is achieved based on an available public IP address, which is the IP address of the CPE, the CPE further transferring the data to the appropriate client device. Such a functionality provides checks before the data is transferred from the CPE to the client devices and allows secure connectivity between the sub-network and the CSP network even when the CPE is mobile, i.e., the location of the CPE is not constant and is changing across various networks.

[0021] During such operations of the CPE in the mobile mode, the CPE carries out mobile internet protocol (MIP) procedures for registering the CPE with a home agent present in a home network. The registration of the CPE with the home agent keeps the home agent informed about the network layer address of the CPE for other devices to communicate with the CPE, when the CPE is in a foreign network. As part of the MIP procedures, when the CPE is in the foreign network, the CPE achieves the registration with the home agent through a foreign agent present in the foreign network.

[0022] However, as the CPE allocates the private IP addresses to the client devices and routes all communication to and from the client devices, the IP addresses of the client devices are masked from other devices outside the sub-network. Therefore, direct IP routing, for example, peer-to-peer connectivity, between a client device in the sub-network and the other devices outside the sub-network, is disabled. Additionally, as a result of the masking of the IP addresses of the client devices, it is difficult to monitor the client devices, say for data tracking.

[0023] On the other hand, in case of a stationary CPE, to allow direct IP to IP routing between a client device in the sub-network and another device outside the sub-network, the above mentioned features implemented in the CPE, such as the NAT and firewall, have to be switched off. However, in such a case, the CPE can be used in stationary mode while providing network routing of the data between various client devices and host devices in the CSP network, since the existing mobile IP procedures are unable to support direct IP routing in mobile CPEs. Hence, in case the CPE is mobile, say the CPE caters to users travelling in a train, the conventional technique may be unable to provide direct IP to IP connectivity from and to the client devices belonging to the sub-network catered to by the CPE. In addition, the connectivity between the client devices and the other devices, in the CSP network outside the sub-network, is achieved based on mapping of IP of the client device and the IP of the other device. As a result, the existing IP to IP mapping may not be reusable. [0024] In certain other conventional modes of providing IP routing between various devices, a technique referred to as virtual private network (VPN) tunneling is employed. Based on the VPN tunneling, IP routing of data between any two interacting devices can be achieved through a VPN server, which may cause unnecessary additional infrastructural costs. Additionally, even with the deployment of this technique, the monitoring of the network usage by client devices exchanging data through the VPN tunneling technique is difficult. For example, it is difficult to track the actual data exchanged between the devices because of the encryption of packets during data transfer. Additionally, the VPN tunneling technique leads to large sized data packets and increased overheads for the systems involved in data exchange

[0025] The present subject matter relates to dynamic allocation of a network layer address to a plurality of client devices connected to a mobile CPE. In an implementation, the mobile CPE can operate at a network layer. In one example, the network layer can be understood as layer 3 of the abstraction layers as defined by Open Systems Interconnection (OSI) 7-layer model. In another example, the network layer can be understood as an internet layer of the abstraction layers as defined by the Transmission Control Protocol/Internet Protocol (TCP/IP) 4-layer model. Further, in an example, the mobile CPE can operate based on internet protocol (IP) procedures and addresses. Further, the mobile CPE can include, but is not limited to, routers and switches operating at the network layer. The mobile CPE can support a sub-network having a plurality of client devices, such as laptops, mobile phones, personal digital agents (PDAs), and personal computers, connected to the mobile CPE as part of a local area network (LAN).

[0026] According to an implementation, the mobile CPE is configured to first request for allocation of a sub-network of network layer addresses (NLAs) for the client devices, along with the network layer address for the mobile CPE itself. Further, for providing mobility support to the mobile CPE, the allocated sub-network of network layer addresses are further passed on for registration using mobile internet protocol (MIP) procedures to ensure connectivity for the client devices in the sub-network of the mobile CPE in a mobile environment as well. In said implementation, the mobile CPE can be configured to request registration of the allocated subnetwork of NLAs and the allocated NLA through an intermediary agent, such as a proxy MIP (PMIP) client. In another implementation, the mobile CPE can be configured to request allocation of the NLA for self and the sub-network of NLAs for the client devices, according to the MIP procedures along with registration. [0027] According to the former implementation, the mobile CPE can be configured to request allocation of the network layer addresses from an IP -based server, such as a dynamic host configuration protocol (DHCP) server. In said implementation, the mobile CPE can transmit, for example, broadcast, a discover message to one or more IP -based servers over the CSP network. According to an aspect of the subject matter, the mobile CPE is configured to insert a subnet request option in the discover message. It will be understood that the IP -based server can be selected from among the plurality of IP -based servers for transmitting the discover message through a relay agent for the IP -based server(s). In the above example, in which the IP- based server is the DHCP server, the mobile CPE can be configured to interact with the DHCP server through a DHCP relay.

[0028] Upon receipt of the discover messages, the IP -based server can determine, based on the discover message including the subnet request option, that the mobile CPE is requesting for allocation of the NLA, say an IP address, for the mobile CPE, and a sub-network of NLAs in addition for allocation to the client devices. In an implementation, in response to the discover message, the one or more IP -based servers, which have available NLAs for allocation, can each send an offer message to the mobile CPE. In an example, the available NLAs can be understood as the NLAs that are yet unallocated to any device. According to an aspect, the offer message can indicate that the NLAs are available. In an example, the offer message can include a subnet response option indicating availability of the sub-network of NLAs for allocation to the client devices. Additionally, in said example, the offer message can further include a subnet mask parameter, which depicts the available sub-network of NLAs and can be used to determine the available NLAs for allocation to the client devices. As will be understood from the above example, the available sub-network can be the sub-network of NLAs not yet allocated to any of the devices, and can include available NLAs therein. For example, the sub-network of network layer addresses are derived by computing a logical AND of the NLA available for the mobile CPE and the subnet mask parameter. Further, the offer message can include the NLA available for the mobile CPE. Further, according to an implementation, the subnet response option in the offer message can notify to the mobile CPE that the available sub-network of NLAs can be further allocated to the client devices.

[0029] Upon receiving the offer messages from the IP -based servers, through the intermediary agent, the mobile CPE can identify and select one IP -based server for getting the NLA for self, and the sub-network of NLAs for the client devices. In an example, the presence of the subnet response option in the offer message can prompt the mobile CPE to accept the offer of the sub-network of NLAs from one of the IP -based servers. Accordingly, the mobile CPE can send a request message to the selected IP -based server. In an example, the request message can indicate an acceptance of the offer of the sub-network of NLAs for further allocation to the client devices and the NLA for the mobile CPE, from the IP -based server. Accordingly, the request message can include, the NLA available for the mobile CPE and the subnet mask parameter.

[0030] In an implementation, before the request message is sent to the IP -based server, the MIP registration of the mobile CPE and the available sub-network can be achieved. Accordingly, the transmission of the request message to the IP-based server is temporarily suspended. In said implementation, the intermediary agent, say the PMIP client, receives the request message having the subnet mask parameter from the mobile CPE and a trigger is set-off for initiating MIP registration. The MIP registration can include registration of the mobile CPE with a mobility agent, such as a home agent or a foreign agent, for supporting mobility of the mobile CPE. In an implementation, for achieving the MIP registration, the intermediary agent can be configured to achieve the MIP registration as part of allocation of NLAs. In another implementation, the foreign agent of the mobile CPE can function as the PMIP client and serve as the intermediary agent for achieving the MIP registration.

[0031] In said implementation, upon receiving the request message from the mobile CPE, as part of the MIP registration, the intermediary agent can send an MIP register request to the mobility agent identified for the mobile CPE. In an example, the mobility agent can be either the home agent or the foreign agent. It will be understood even in case of the mobility agent being the foreign agent, the MIP register request is finally routed to the home agent for achieving the MIP registration. According to an aspect, the MIP register request can include the NLA for the mobile CPE and the subnet mask parameter, received in the request message from the mobile CPE.

[0032] In response to the MIP register request, the home agent can determine whether the allocation of the NLA for the mobile CPE and the sub-network for the client devices, provided by IP -based server are acceptable or nor. In case the NLA and the sub-network are not acceptable, the transmission of the request message, temporarily suspended by the intermediary agent, is permanently stalled and not forwarded to the IP -based server. Accordingly, a lease duration of the request message is allowed to expire. In an implementation, upon the expiry of the lease duration for the request message, the mobile CPE can re-start the process of getting the NLAs allocated by sending the discover message.

[0033] On the other hand, if the NLA and the sub-network are acceptable, the home agent sends an MIP register response to the intermediary client. The MIP register response is indicative of the successful completion of the MIP registration of the mobile CPE with the home agent. Further, as part of the MIP registration, the home agent can associate the available NLAs for allocation to the client devices with an NLA of the home agent. In addition, the NLAs for allocation to the client devices can also be associated with an NLA of the foreign agent. According to an implementation, the home agent can derive the NLAs for allocation to the client devices, based on the subnet mask parameter, and associate those NLAs with the NLA of the home agent. In such a case, the available NLAs for allocation to the client devices can be determined based on the subnet mask parameter associated with the NLAs of the home agent and the foreign agent when data is to be routed to the client devices. Hence, a similar effect as that achieved in case of association of the actual NLAs for the client devices can be achieved. [0034] Further, the association of the NLAs for the client devices and that of the home agent and the foreign agent can be understood as an establishment of a mapping between the mobile CPE, the home agent, and the foreign. As a result, a single NLA-in-NLA tunnel, say an IP-in-IP tunnel, includes a single NLA of the home agent mapped to the sub-network of NLAs allocated to the client devices. As a result, the mapping can be used for achieving direct routing of data between the client devices and the host devices, since the NLAs allocated to the client devices are not masked and are public.

[0035] In an example, the MIP register response can be in the same format as the MIP register request. In said example, the MIP register response can also include the accepted NLA for the mobile CPE and the available sub-network of NLAs for allocation to the client devices.

[0036] In the event of change in the location of the mobile CPE to another foreign network, the mobile CPE may again initiate the process of MIP registration with the mobility agent, for example, a foreign agent in the other network in this case, in the same manner as described above. Hence, the dynamically allocated NLAs for the client devices are now provided to the new foreign agent and the home agent is provided information about the change in location of the CPE and the associated client devices. As a result, the mobile CPE, along with the associated client devices, can achieve seamless connectivity with the host devices over the CSP network.

[0037] In addition, as mentioned previously, according to another implementation of the present subject matter, the mobile CPE can be configured to request allocation of the NLAs, including the NLA for self and the sub-network of NLAs for the client devices, without implementing the intermediary client, such as the PMIP client. Accordingly, the mobile CPE can be configured as an MIP client and can implement the functionalities associated with the proxy MIP client, as discussed earlier. For example, the mobile CPE is capable of achieving the MIP registration with the mobility agent, say the home agent through the foreign agent, in case the mobile CPE is in the foreign network. [0038] According to an implementation, for achieving the MIP registration and the allocation of the NLAs and the sub-network, the mobile CPE can first initiate establishment of a connection with the mobility agent. As is explained earlier, the mobility agent can be the home agent or the foreign agent catering to the mobile CPE, based on the location of the mobile CPE being in the home network or the foreign network. In said implementation, to do so, the mobile CPE transmits, for example, broadcasts, an agent solicitation message to the mobility agents in the network. In response to the agent solicitation message, the mobility agent can send an agent advertisement to the mobile CPE. In an implementation, the mobility agent can send a care-of- address, say representing an NLA allocated for the mobile CPE, along with the agent advertisement. The receipt of the agent advertisement notifies the mobile CPE that the connection with the mobility agent has been established and the mobile CPE can communicate with the mobility agent for achieving the MIP registration of the mobile CPE. In an example, it can be understood that the receipt of the agent advertisement triggers mobile CPE to initiate the registration procedure as discussed with reference to the previous implementation.

[0039] As will be understood that, in the above implementation, if the mobile CPE is in the home network, then the mobile CPE can achieve the registration by directly communicating with the home agent. Further, in the event of change in location of the mobile CPE, the mobile CPE re-registers with the foreign agent or the home agent, as the case may be, in the network that the mobile CPE is currently located in, in the same manner as described above. In an implementation, while sending the MIP register request, the mobile CPE sends a default subnet mask parameter in the MIP register request indicating a request for providing the sub-network of NLAs for the client devices. In an example, the default subnet mask parameter can be 0.0.0.0. Additionally, the home agent, when sending the MIP register response, also includes the subnet mask parameter in the MIP register response. Based on the subnet mask parameter, the subnetwork of NLAs and the actual NLAs for allocation to the client devices can be derived as described earlier. Further, as mentioned previously, the completion of MIP registration can also include association of the NLAs for allocation to the client devices with the NLA of the home agent and, optionally, with the NLA of the foreign agent.

[0040] According to an aspect, in both the above implementations, once the MIP registration is completed and the mobile CPE has received the NLA for self and the sub-network of NLAs for allocation to the client devices, the mobile CPE can function as a proxy IP -based server, and allocate the NLAs to the client devices based on the available sub-network of NLAs indicated by the subnet mask parameter.

[0041] Further, in both the above implementations, once a client device disconnects from the mobile CPE, the address is returned to the mobile CPE and can be allocated by the mobile CPE to another client device that joins the mobile CPE. In addition, in case the mobile CPE exits the network, and, for example, the whole sub-network of NLAs is released by the mobile CPE, then accordingly the IP -based server or the home agent is informed about such release so that the released NLAs can be re-allocated to another set of mobile CPEs and client devices.

[0042] As mentioned previously, once the mobile CPE is registered with the home agent, the home agent can associate the available NLAs for allocation to the client devices with an NLA of the home agent. In another example, the home agent can associate the sub-network of NLAs, instead of the individual NLAs, with the NLA of the home agent. Based on the association, the routing of data between the client devices and the host devices can be achieved. Additionally, the NLAs for the client devices, or in another case, the subnet mask parameter, are mapped to the NLA of the foreign agent to achieve the direct routing of data between the individual client devices and the host devices.

[0043] According to an aspect, as a result of dynamic allocation of network layer addresses to the mobile CPE and further to the client devices catered to by the mobile CPE, seamless connectivity can be provided between each of the client devices and other devices over the network. Hence, the mobile CPE can be used for mobile applications, for example, to cater to users travelling in a train, when the mobile CPE and the client devices have continually changing network locations. Additionally, since the NLAs available for allocation to the client devices are made public to the foreign agent and the home agent, the other devices are able to directly route data to each client device based on the publically routable NLA of the client device. Hence, the other devices are able to communicate with the client devices connected to the mobile CPE at NLA level. As a result, the data transfer between each client device and the CSP network can be easily monitored and tracked. Therefore, according to the subject matter, the mobile CPE is capable of providing direct routing to the individual client device in the sub-network, for example, for peer-to-peer communication, while on the move.

[0044] The manner in which the systems and methods for dynamic allocation of network layer addresses to the client devices connected to the mobile CPE are implemented shall be explained in details with respect to the figures. While aspects of described systems and methods for achieving real-time interactions in a communication network can be implemented in any number of different computing systems, environments, and/or configurations, the embodiments are described in the context of the following exemplary system(s).

[0045] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.

[0046] It will also be appreciated by those skilled in the art that the words during, while, and when as used herein are not exact terms that mean an action takes place instantly upon an initiating action but that there may be some small but reasonable delay, such as a propagation delay, between the initial action and the reaction that is initiated by the initial action. Additionally, the word "connected" is used throughout for clarity of the description and can include either a direct connection or an indirect connection. [0047] Figure 1 illustrates a network environment 100 implementing a mobile consumer premises equipment (CPE) 102. The mobile CPE 102 can be connected to and support a plurality of client devices 104-1 , 104-2 ...104-N, collectively referred to as the client devices 104 and individually referred to as the client device 104. In operation, the mobile CPE 102 can be configured to request and achieve dynamic allocation of network layer addresses (NLAs), such as internet protocol (IP) addresses, to each of the client devices 104. In an example, the NLAs allocated to the client device 104 are publically routable NLAs. The mobile CPE 102 can be understood as a CPE capable of providing connectivity to the client devices 104 while in a mobile mode, i.e., when the location of the mobile CPE 102 and the client devices 104 is changing various networks. For example, the mobile CPE 102 can be provided on-board a train or a bus, to provide mobile connectivity to user devices, while travelling on the train or the bus.

[0048] According to an implementation, the mobile CPE 102 can operate at a network layer. In one example, the network layer can be understood as layer 3 of the abstraction layers as defined by Open Systems Interconnection (OSI) 7-layer model. In another example, the network layer can be understood as an internet layer of the abstraction layers as defined by the Transmission Control Protocol/Internet Protocol (TCP/IP) 4-layer model. Accordingly, the mobile CPE 102 can be understood to be a network layer device, and in an example, the mobile CPE 102 can operate based on internet protocol (IP) procedures and addresses. Further, the mobile CPE 102 can include, but is not limited to, routers and switches operating at the network layer. In addition, the mobile CPE 102 can be implemented on other devices, such as a laptop computer, a desktop computer, a notebook, a workstation, a mainframe computer, a server, and a network server.

[0049] The client devices 104, on the other hand, can include, without limitation, desktop computers, hand-held devices, laptops or other portable computers, tablet personal computers, network computers, mobile phones, multi-media enabled phones, and smart phones.

[0050] The mobile CPE 102 and the client devices 104 can communicate with each other over a local network 106. The local network 106 may be a wireless or a wired network, or a combination thereof. According to an example, the local network 106 can be implemented as one of the different types of networks, such as intranet, local area network (LAN), wide area network (WAN), and the internet. The local network 106 may either be a dedicated network or a shared network, which represents an association of the different types of networks that use a variety of protocols, for example, Hypertext Transfer Protocol (HTTP), Transmission Control Protocol/Internet Protocol (TCP/IP), and Wireless Application Protocol (WAP), to communicate with each other. Further, the local network 106 may include a variety of network devices, including routers, bridges, servers, computing devices, storage devices.

[0051] The mobile CPE 102 is further connected to a communication network 108 through which the mobile CPE 102 and the client devices 104 interact with various other devices, such as host devices 128. In an example, the communication network 108 can be a wireless or a wired network, or a combination thereof. In an example, the communication network 108 can be implemented as a radio access network (RAN). In said example, the communication network 108 can be a collection of individual networks, interconnected with each other and functioning as a single large network (e.g., the internet or an intranet). Examples of such individual networks include, but are not limited to, Worldwide Interoperability for Microwave Access (WiMAX) networks, Long Term Evolution (LTE), networks and other IP -based networks.

[0052] In an implementation, the mobile CPE 102 includes a processor(s) 110 coupled to a memory 1 12. The mobile CPE 102 further includes interface(s) 114, for example, to facilitate communication with the client devices 104 over the local network 106 and with other devices over the communication network 108. The interface(s) 1 14 may include a variety of software and hardware interfaces, for example, interfaces for peripheral device(s), such as a keyboard, a mouse, an external memory, and a printer. Further, the interface(s) 114 enables the mobile CPE 102 to communicate with other devices, such as web servers and external repositories. The interface(s) 114 can also facilitate multiple communications within a wide variety of networks and protocol types, including wired networks, for example, LAN, cable, etc., and wireless networks, such as WLAN, cellular, or satellite. For the purpose, the interface(s) 1 14 may include one or more ports.

[0053] The processor(s) 1 10 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. Among other capabilities, the processor(s) 1 10 are configured to fetch and execute computer-readable instructions stored in the memory 112. [0054] The memory 112 can include any computer-readable medium known in the art including, for example, volatile memory, such as static random access memory (SRAM) and dynamic random access memory (DRAM), and/or non-volatile memory, such as read only memory (ROM), erasable programmable ROM, flash memories, hard disks, optical disks, and magnetic tapes. Further, the memory 1 12 includes module(s) 116 and data 1 18. [0055] The module(s) 116 include, for example, a mobile internet protocol (MIP) registration module 120, an allocation module 122 and other module(s) 124. The other module(s) 124 may include programs or coded instructions that supplement applications or functions performed by the mobile CPE 102.

[0056] The data 1 18 can include allocated network layer address (NLA) data 126 and other data 127. The other data 127, amongst other things, may serve as a repository for storing data that is processed, received, or generated as a result of the execution of one or more modules in the module(s) 1 16. Although the data 118 is shown internal to the mobile CPE 102, it may be understood that the data 1 18 can reside in an external repository (not shown in the figure), which may be coupled to the mobile CPE 102. The mobile CPE 102 may communicate with the external repository through the interface(s) 114 to obtain information from the data 118.

[0057] As mentioned previously, the mobile CPE 102 is configured to request and achieve dynamic allocation of NLAs, such as internet protocol (IP) addresses, to the client device 104. In an example, as would be understood, the dynamic allocation of NLAs for the client devices 104 is achieved in case location of the client devices 104 is changing, i.e., the client devices 104 are mobile and changing networks. According to an implementation, the individual NLAs allocated to the client devices 104 are made publically routable, and hence, allow the client devices 104 to directly interact with the host devices 128, such as correspondent nodes, over the communication network 108.

[0058] According to an aspect, for achieving the dynamic allocation of NLAs for the client devices 104, the mobile CPE 102 obtains available NLAs for allocation to the client devices 104 and registers the available NLAs. Accordingly, the mobile CPE 102 can obtain the available NLAs and achieve procedures, such as registration based on mobile internet protocol (MIP) referred to as MIP registration, either simultaneously or in multiple steps. The MIP registration of the mobile CPE 102 allows the client devices 104, connected to the mobile CPE 102, to perpetually interact with the host devices 128 while roaming on various networks in the communication network 108. In an implementation, the mobile CPE 102 registers itself, say according to MIP registration procedures, at a home agent 130. In order to connect to the home agent 130, the mobile CPE 102 can connect with a mobility agent in the communication network 108. In an example, in case the mobile CPE 102 is in a home network, then the mobility agent is the home agent 130 to which the mobile CPE 102 connects directly. In another example, in case the mobile CPE 102 is in a foreign network, then the mobility agent is a foreign agent 132. In said example, the foreign agent 132 further connects the mobile CPE 102 to the home agent 130. The home network can be understood as the network in which the mobile CPE 102 is registered. In an example, the home agent 130 and the foreign agent 132 can be implemented as a computing device, such as a laptop computer, a desktop computer, a notebook, a workstation, a mainframe computer, a server, or a network server.

[0059] As mentioned previously, in an implementation, the registration module 120 of the mobile CPE 102 can be devoid of the functionality of achieving the MIP registration. In said implementation, the registration module 120 can be obtain an NLA for the mobile CPE 102 and the NLAs for allocation to the client devices 104, say from an IP -based server 134, and then subsequently trigger the MIP registration by an intermediary agent. In an example, the intermediary agent can be a proxy MIP (PMIP) client (not shown in figure). Further, in one example, the mobile CPE 102 can connect to the IP -based server 134, say through a relay agent 136. In an example, the IP -based servers 134 can be a dynamic host configuration protocol (DHCP) servers, implemented as say, as a laptop computer, a desktop computer, a notebook, a workstation, a mainframe computer, a server, and a network server. Accordingly, in said example in which the IP -based server 134 is the DHCP server, the relay agent 136 can be a DHCP relay.

[0060] In another implementation of the present subject matter, the registration module 120 can be configured to interact with the home agent 130 and request allocation of the NLAs the home agent 130, for example, along with the MIP registration with the home agent 130. The latter implementation is discussed later.

[0061] According to the former implementation, the registration module 120 can interact with the IP -based servers 134 to request allocation of an NLA for the mobile CPE 102 and a sub- network of NLAs for the client devices 104. During such requests, the registration module 120 can include a subnet request option in a discover message exchanged with the IP -based servers 134. The subnet request option in the messages from the mobile CPE 102 to the IP -based servers 134 can indicate a request to obtain the sub-network of NLAs for allocation to the client devices 104. Based on the subnet request option received from the mobile CPE 102, one or more available IP -based servers from among the IP -based servers 134 can be configured to respond with an offer message to the mobile CPE 102 through the relay agent 136.

[0062] According to an implementation, the offer message from each of the available IP- based servers 134 can include a subnet response option indicating that a sub-network of NLAs is available for allocating NLAs to the client devices 104. Additionally, the offer message can also include a subnet mask parameter indicating the availability of the sub-network of NLAs for allocation to the client devices 104. In an example, the subnet mask parameter can be used to determine the actual sub-network and NLAs available for the client devices 104. Say, the subnet mask parameter can be 255.255.255.0, and the sub-network determined based on the subnet mask parameter can be 192.168.0.0/24. In an aspect, accordingly, the subnet response option can indicate a permit for the mobile CPE 102 to allocate NLAs to the client devices 104 based on the subnet mask parameter. Further, the IP -based server can include the NLA available for the mobile CPE 102.

[0063] In another implementation, the mobile CPE 102 can interact with a selected IP- based server 134. In said implementation, the registration module 120 can identify and select the IP -based server 134 to be communicated with for sending the subnet request option and requesting the sub-network of NLAs. As mentioned above, in case the selected IP -based server 134 has an available sub-network for providing to the mobile CPE 102, the selected IP -based server 134 can respond and provide the offer message to the mobile CPE 102. According to said implementation, the registration module 120 can be configured to continually identify IP -based servers 134 over the communication network 108 and send the subnet request option, till the offer message is obtained from one of the IP -based servers 134. In an example, the presence of the subnet response option in the offer message can prompt the mobile CPE 102 to accept the offer of the sub-network of NLAs from the IP -based servers 134.

[0064] In said implementation, once the offer request, having the subnet response option, is obtained from the IP -based server 134, the registration module 120 can then initiate registration of the allocated sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102, with the IP -based server 134. In an implementation, to initiate the registration procedure, the registration module 120 can send a request message towards the IP -based server 134 which is received by the PMIP client for forwarding to the IP -based server 134. The request message can include the subnet mask parameter obtained from the IP -based server 134 along with the offer message.

[0065] According to an implementation, on receipt of the request message from the mobile CPE 102, the PMIP client triggers the MIP registration of the mobile CPE 102, as part of which the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102, with the mobility agent. Accordingly, to achieve the MIP registration, the PMIP client generates an MIP register request. In an implementation, the PMIP client can include the subnet mask parameter in the MIP register request. As explained earlier, in case the mobile CPE 102 is outside the home network, the PMIP client can send the MIP register request to the foreign agent 132, which further routes the MIP register request to the home agent 130. Further, in the implementation, the PMIP client is co-located with the foreign agent 132, and in this case the MIP register request is forwarded from the PMIP client-foreign agent co-located unit to the home agent 130. In addition, the transmission of the request message further to the IP -based server 134 is temporarily stalled, and the request message is stored with the PMIP client for the time being.

[0066] Subsequently, the home agent 130 can receive the MIP register request, parse the request, for example, to determine whether the subnet mask parameter is present in the MIP register request or not. In said example, in case the subnet mask parameter is present, the home agent 130 can determine whether the available sub-network of NLAs for allocation, indicated by the subnet mask parameter, is acceptable or not. In case the sub-network is not acceptable, the transmission of the request message, pending with the PMIP client, is permanently suspended and a lease duration of the request message is allowed to expire. In an example, the lease duration can be understood as the time duration of validity.

[0067] On the other hand, in case the sub-network of NLAs is accepted by the home agent 130, the home agent 130 can successfully achieve the MIP registration of the mobile CPE 102 and the client devices 104. According to an implementation, during the registration at the home agent 130, the home agent 130 can, in one example, associate the NLAs for allocation to the client devices 104 with an NLA of the home agent 130. In said example, the home agent 130 can determine the NLAs for the client devices 104 based on the subnet mask parameter. Say, the home agent 130 can compute a logical AND of the NLA for the mobile CPE 102 and the subnet mask parameter to obtain the NLAs for allocation to the client devices 104 and then associate the NLAs with the NLA of the home agent 130.

[0068] In another example, as part of association, the home agent 130 can associate the subnet mask parameter in the MIP register request, with the NLA of the home agent 130. Further, in an implementation, the home agent 130 can send an MIP register response to the foreign agent 132. The foreign agent 132 can further send the MIP register response to the mobile CPE 102, indicating that the MIP registration has been successful. In an example, the foreign agent 132 can send the MIP register response for the mobile CPE 102 through the PMIP client. In another example, the foreign agent 132 can be co-located with the PMIP client on the same device, and in this case, the MIP register response can be received at the PMIP client- foreign agent co-located unit and further sent to the mobile CPE 102. As will be understood, the receipt of the MIP register response at the foreign agent 132 and subsequently at the mobile CPE 102 indicates that the NLAs for allocation to the client devices 104 have been associated with the NLA of the home agent 130. Additionally, in an implementation, the NLAs allocated to the client devices 104 can also be associated with an NLA of the foreign agent 132 when the MIP register response is routed back to the mobile CPE 102, in the same manner as described above with reference to association with the NLA of the home agent 130. As a result of the association, the home agent 130 and the foreign agent 132 can establish a connection with the mobile CPE 102. In an example, the connection can be understood to be established in terms of an NLA-in- NLA tunnel, say an IP-in-IP tunnel. Such a connection allows the home agent 130 to directly route data from one or more host devices 128 in the communication network to the individual client devices 104.

[0069] As mentioned previously, in another implementation, the mobile CPE 102 can be configured to interact with the home agent 130, say through the foreign agent 132 in case the mobile CPE 102 is in the foreign network, and achieve the MIP registration with the home agent 130. According to an aspect, the registration module 120 can additionally request the subnetwork of NLAs for the client devices 104 and the NLA for the mobile CPE 102 from the home agent 130, while carrying out the MIP registration. In an example, in said implementation, the registration module 120 can be understood to be configured with the capabilities and functionalities of the PMIP client. As mentioned earlier, in order to communicate with the home agent 130, the mobile CPE 102 can connect with the mobility agent in the communication network 108, which in one example, in case the mobile CPE 102 is in a home network, is the home agent 130, and, in case the mobile CPE 102 is in a foreign network, is the foreign agent 132. In the latter case, the foreign agent 132 further connects the mobile CPE 102 to the home agent 130.

[0070] According to said implementation, the registration module 120 can first identify the mobility agent in the communication network 108 catering to that mobile CPE 102 connect to the home agent 130. Once the mobility agent has been identified, the mobile CPE 102 triggers the initiation of the MIP registration procedure by sending the MIP register request to the mobility agent, which can be either the home agent 130 or the foreign agent 132. In either case, the MIP register request is finally received by the home agent 130.

[0071] According to an aspect, as part of requesting the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102, the registration module 120 send insert a default subnet mask subnet mask parameter in the MIP register request. In an example, since the default subnet mask parameter can have a value of 0.0.0.0. Further, the processing of the MIP register request can be achieved by the home agent 130 in the same manner as described above. When the MIP register request, having the default subnet mask parameter therein, is received, the home agent 130 can determine whether the MIP register request is acceptable or not.

[0072] In case the MIP register request is acceptable, in an implementation, the home agent 130 can allocate the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102, and achieve the registration of the mobile CPE 102 and the client devices 104. In an example, to indicate the successful registration, the home agent 130 can send the MIP register response to the mobile CPE 102, say through the mobility agent, i.e., the foreign agent 132. The MIP register response including the NLA for the mobile CPE 102 and the subnet mask parameter is included in the MIP register response to indicate the allocated sub-network. For example, as mentioned earlier, the default subnet mask parameter can be updated from 0.0.0.0 to 255.255.255.240. Further, as described earlier, as part of successful registration, the home agent 130 can associate the NLAs for allocation to the client devices 104, say determined based on the subnet mask parameter included in the MIP register response, to the NLA of the home agent 130. Based on the above example, in case the subnet mask parameter is 255.255.255.240, the sub- network can be determined as 192.168.1.0/28. In addition, as mentioned earlier, the NLAs can be associated with the NLA of the foreign agent 132 when the MIP register response is routed back to the mobile CPE 102. Further, in an example, the home agent 130 can include the NLA for the mobile CPE 102 in a home address field in the MIP register response.

[0073] On the other hand, in case the MIP register request is not acceptable, for example, the sub-network of NLAs is unavailable for allocation, then, the home agent 130 can allow the lease duration of the MIP register request to expire, and send an error message to the mobile CPE 102.

[0074] Further, in both the above mentioned implementations of the subject matter, the mobile CPE 102, after obtaining the sub-network of NLAs, serves as a proxy IP -based server. According to an aspect, while functioning as the proxy IP -based server, the allocation module 122 in the mobile CPE 102 can allocate the individual NLAs to the client devices 104, based on the sub-network obtained from the IP -based server 134 or the home agent 130. When the host devices 128 try to establish a connection with the client devices 104 through the home agent 130 and/or the foreign agent 132, the individual NLAs registered with either of the home agent 130 and the foreign agent 132 can be used to directly route the data individually to the client devices 104. Thus, the NLAs dynamically allocated to the client devices 104 are publically routable and can be used by the host devices 128 to directly communicate with the client devices 104, making the mobile CPE 102 a transparent node during, say the peer-to-peer communications between the client devices 104 and the host devices 128.

[0075] In addition, in an implementation, once a client device 104 disconnects from the mobile CPE 102, the address is returned to the mobile CPE 102 and can be allocated to another client device that joins the mobile CPE 102. Further, to implement this functionality, in an implementation, the lease duration of allocation of NLAs to the mobile CPE 102 is greater than the lease duration of allocation of NLAs to the client devices 104.

[0076] Additionally, in case the mobile CPE 102 leaves the network, in an example, the whole sub-network of NLAs, is released by the mobile CPE 102. Then accordingly, the device allocating the sub-network are informed about such release so that the released sub-network can be re-allocated to another requesting set of mobile CPEs and client devices. For example, in case the sub-network is allocated by the IP -based server 134, then a release message including the subnet mask parameter, indicating the released sub-network, is sent to the IP -based server 134 by the mobile CPE 102 to inform about the release. In another example, in case the sub-network has been allocated by the home agent 130, then the mobile CPE 102 can send an MIP deregister request having the subnet mask parameter to the home agent 130.

[0077] Figure 2 illustrates a data flow diagram 200 indicating dynamic allocation of NLAs to the client devices 104, according to an implementation of the present subject matter. In an example, figure 2 illustrates the data flow diagram 200 in case the mobile CPE 102 the MIP registration through the PMIP client implemented in the communication network 108. As mentioned earlier, in such implementation, the registration module 120 of the mobile CPE 102 is responsible for obtaining the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102 from the IP -based server 134. As explained earlier, in such a case, the registration module 120 may be devoid of the functionality to achieve MIP registration with the home agent 130.

[0078] As explained earlier, in said implementation, the mobile CPE 102 initiates the process of allocation of NLAs for self and the client devices 104 automatically as soon as the mobile CPE 102 is switched on. As will be understood, the mobile CPE 102 is configured to achieve dynamic allocation of the NLAs. Further, the registration module 120 can initiate the NLA allocation process by requesting to obtain the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102 from the IP -based servers 134, say the DHCP server. Accordingly, at step 202, the registration module 120 transmits a discover message towards the IP -based servers 134. According to an aspect, the discover message can include the subnet request option to indicate to the IP -based servers 134 that the allocation of sub-network of NLAs is being requested. In an example, the discover message is depicted by a proprietary code 250, which is inserted in the discover message as the subnet request option. In an example, as depicted in figure 2, the discover message can be transmitted by the registration module 120 through the intermediary agent, which in this case is the relay agent 136.

[0079] In an implementation, the discover message is intercepted by the intermediary agent, for example, the relay agent 136, in this case. As mentioned previously, in an example, the discover message broadcast to the IP -based servers 134 and intercepted by the relay agent 136, can then be transmitted to the selected IP -based server 134. In another example, the discover message can by-pass the relay agent 136 and directly reach a plurality of IP -based servers 134. The receipt of the discover message at the IP -based server 134 is depicted by the step 204. [0080] Subsequently, the IP -based server 134 can parse the discover message and, upon determining that the discover message includes the subnet request option, the IP -based server 134 can respond to the discover message. In an example, in case the discover message is broadcast to the plurality of IP -based servers 134 in the communication network 108, the available IP -based servers 134, i.e., the IP -based servers 134 having a sub-network of NLAs for allocation, can respond to the discover message. As depicted in step 206, in an implementation, the available IP -based servers 134 can each send an offer message to the mobile CPE 102, say through the PMIP client.

[0081] In said implementation, the offer message can include a subnet response option and the NLA for the mobile CPE 102 and the subnet mask parameter. In an example, the subnet response option can be included in the offer message in the form of a proprietary code 251. As mentioned earlier, the subnet response option can indicate the availability of the sub-network of NLAs to allocate to the client devices 104, and also indicates an authorization to the mobile CPE 102 to use the subnet mask parameter and allocate the NLAs to the client devices 104 based on that subnet mask parameter. Additionally, the subnet mask parameter in the offer message can indicate the sub-network of NLAs available for allocation for the client devices 104.

[0082] In one example, the subnet mask parameter can be used to determine the actual NLAs available for allocation to the client devices 104 from the sub-network. Say, the subnetwork of NLAs can be derived by computing a logical AND of the NLA for allocation to the mobile CPE 102 and the subnet mask parameter. Hence, if 192.168.1.1 is the NLA address available for the mobile CPE 102 and the subnet mask parameter is 255.255.255.240, then the sub-network of NLAs is depicted by 192.168.1.0/28. In said example, the sub-network of NLAs is collectively depicted by the above mentioned notation. Accordingly, in said example, the NLAs allocated for the client devices 104 are in the range of 192.168. 1.0 to 192.168.1.15.

[0083] At step 208, the offer messages received from the available IP -based servers 134 by the PMIP client are forwarded to the mobile CPE 102. In an example, the presence of the subnet response option in the offer message can prompt the mobile CPE 102 to accept the offer of the sub-network of NLAs from one of IP -based servers 134. Accordingly, in an implementation, upon receiving the offer message, the registration module 120 can identify and select one IP- based server 134 from the available IP -based servers 134 for obtaining the NLA for the mobile CPE 102 and the sub-network of NLAs for the client devices 104. Once the IP -based server 134 is selected, at step 210, the registration module 120 transmits the request message to the IP -based server 134, for confirming and registering the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102, says through the PMIP client. In an implementation, the request message can include the NLA available for allocation to the mobile CPE 102 and the sub-network of NLAs available for allocation to the client devices 104.

[0084] According to an aspect, the request message sent by the registration module 120 is first received, say through the relay agent 136, at the PMIP client. Upon receipt of the request message, the PMIP client initiates the MIP registration procedure for the mobile CPE 102. In an example, the relay agent 136 can be co-located with the PMIP client, i.e., the relay agent 136 can be implemented on the same physical devices as that implementing the PMIP client. In an implementation, upon receipt of the request message from the registration module 120, the PMIP client generates the MIP register request for sending to the home agent 130. In an example, the MIP register request can include the NLAs available for allocation, for example, the NLA for the mobile CPE 102 and the NLAs for the client devices 104. Accordingly, the MIP register request can include the NLA available for allocation to the mobile CPE 102 in a home address field and the subnet mask parameter in a subnet mask field in the MIP register request. In the meanwhile, the transmission of the request message further to the IP -based server 134 is temporarily stalled until the MIP registration is successfully achieved.

[0085] As will be understood, the MIP register request is sent from the PMIP client to the home agent 130, through the foreign agent 132. As explained earlier also, the functionalities of the foreign agent 132 and the PMIP client can be provided on the same hardware equipment, i.e., the foreign agent 132 and the PMIP client can be co-located. The transmission of the MIP register request from the foreign agent 132 is depicted at step 212.

[0086] The MIP register request received at the home agent 130 can be parsed to determine the presence of the subnet mask parameter in the MIP register request, based on which, the home agent 130 determines that the MIP register request is for MIP registration of the mobile CPE 102 and the client devices 104, and the respective NLAs. Accordingly, in case the MIP register request is acceptable, for example, determined based on the acceptability of the NLA for the mobile CPE 102 and the sub-network of NLAs for the client devices 104, and a syntax of the MIP register request, the home agent 130 successfully registers the mobile CPE 102 and the client devices 104. Accordingly, in an implementation, as part of the MIP registration, the home agent 130 associates, in one example, the NLAs for the client devices 104, and in another example, the subnet mask parameter, with the NLA of the home agent 130.

[0087] Upon successful MIP registration, the home agent 130 sends the MIP register response to the mobile CPE 102, through the mobility agent, i.e., the foreign agent 132, say in the same format as the MIP register request. In said example, the MIP register response can include the NLA for the mobile CPE 102 in the home address field and the subnet mask parameter in the subnet mask field. The transmission of the MIP register response from the home agent 130 to the foreign agent 132 is depicted at step 214. Further, when the MIP register response is routed through the foreign agent 132, the NLA of the foreign agent can also be associated with either the individual NLAs for the client devices 104 or the sub-network of NLAs for allocation to the client devices 104. According to an aspect, the receipt of the MIP register request, say at the PMIP client, indicates successful MIP registration at the home agent 130, and triggers the transmission of the request message further.

[0088] Further, at step 216, the request message received from the registration module 120 at the PMIP client and put on hold, is forwarded to the IP -based server 134 by the PMIP client. As mentioned previously, the request message includes the NLA for the mobile CPE 102 and the subnet mask parameter. The request message serves as a confirmation message to the IP -based server 134, in which the registration module 120 of the mobile CPE 102 finally accepts the provided NLA for the mobile CPE 102 and the sub-network of NLAs for the client devices 104 from the IP -based server 134.

[0089] On the other hand, if the MIP registration is not successful because, for example, the NLAs available for allocation are not acceptable to the home agent 130 or the syntax of the MIP register request is incorrect, then, in an implementation, the PMIP client does not receive the MIP register response. In the absence of the MIP register response, the PMIP client suspends the forwarding of the request message to the IP -based server 134. As a result, the lease period for the request message is allowed to expire.

[0090] In response to the request message, the IP -based server 134 transmits an acknowledgement message to the PMIP client, as shown at step 218. The acknowledgment message indicates that the NLAs offered to the mobile CPE 102 and the client devices 104 for allocation, have been allocated. The PMIP client further sends the acknowledgement message to the mobile CPE 102, as shown at step 220. [0091] As explained previously, with the successful completion of the MIP registration of the mobile CPE 102 and the client devices 104 and receipt of the acknowledgement message from the IP -based server 134, in an implementation, the allocation module 122 serves as the proxy IP -based server 134 and allocates the individual NLAs to the connected client devices 104 based on the subnet mask parameter. Further, the allocation module 122 can maintain a table or other appropriate record of the sub-network of NLAs allocated to the client devices 104 and the actual NLAs allocated to each of the individual client devices 104, for example, in the allocated NLA data 126.

[0092] Additionally, in case of deregistration of any one or all of the client devices 104, the sub-network of NLAs is released and communicated to the IP -based server 134 or the home agent 130, or both. The same released NLAs are then available for allocation to other client devices in the communication network 108.

[0093] Figure 3 illustrates the data flow diagram 300 indicating dynamic allocation of NLAs for the client devices 104, according to another implementation of the present subject matter. In an example, figure 3 illustrates the data flow diagram 300 in case the mobile CPE 102 achieves the allocation of the sub-network NLAs in tandem with the MIP registration with the home agent 130, say through the mobility agent, by interacting with the devices directly, i.e., without the intervention of the PMIP client. As mentioned earlier, in said implementation, the registration module 120 of the mobile CPE 102 is configured as the MIP client. In an example, figure 3 illustrates the scenario in which the mobile CPE 102 is in a foreign network, and hence, the MIP registration and the subsequent allocation of the NLAs are achieved through the mobility agent. The mobility agent in this scenario can be the foreign agent 132.

[0094] As mentioned previously, the mobile CPE 102 initiates the allocation of NLAs for self and the connected client devices 104 upon being switched on and establishing connectivity over the communication network 108. In said implementation, the registration module 120 requests for MIP registration as well as for allocation of the NLAs from the home agent 130. Hence, in said implementation, the home agent 130 is configured to allocate the NLA for the mobile CPE 102 and the sub-network of NLAs for the client devices 104.

[0095] According to said implementation, the registration module 120 initiates the MIP registration, say of the mobile CPE 102 and the client devices 104, at step 302 by broadcasting an agent solicitation message in the communication network 108. The agent solicitation message can be broadcast for the mobility agents in the communication network 108. In an example, the agent solicitation message can be an Internet Control Message Protocol (ICMP) agent solicitation message. Further, the mobility agent in the home network can be the home agent 130, and in the foreign network can be the foreign agent 132.

[0096] At step 304, an agent advertisement is received by the registration module 120 from one or more available mobility agents. In an implementation, the agent advertisement can include a care-of-address indicating the NLA offered for allocation to the mobile CPE 102 by the mobility agent sending the agent advertisement. In an example, in case the agent advertisement is received from more than one available foreign agent 132, then the registration module 120 can select a suitable foreign agent 132 from among the available foreign agents 132, and further carry out the MIP registration procedure with the selected foreign agent 132. In addition, as mentioned previously, the registration module 120 can request for allocation of the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102.

[0097] In response to the agent advertisement and the selection of the foreign agent 132 for MIP registration procedure, the registration module 120 transmits the MIP register request to the foreign agent 132. The transmission of the MIP register request from the registration module 120 to the foreign agent 132 is depicted by step 306. According to an aspect, the registration module 120 can include the default subnet mask parameter in the MIP register request, say in a subnet mask field in the MIP register request, indicating the request for allocation of NLAs. According to an aspect, the presence of the subnet mask field in the MIP register request indicates that the mobile CPE 102 is requesting for allocation of the sub-network for the client devices 104 and the NLA for the mobile CPE 102. For example, the default subnet mask parameter can be 0.0.0.0.

[0098] Further, the MIP register request is sent from the foreign agent 132 to the home agent 130, as depicted at step 308. In an implementation, the home agent 130 can parse the MIP register request. In an example, based on the presence of the subnet mask parameter and/or the subnet mask field, the home agent 130 can determine that the MIP register request includes a request for the allocation of the sub-network of NLAs for the client devices 104. Upon establishing the acceptability of the MIP registration request, in the same manner as explained with reference to figure 2, the home agent 130 successfully registers the mobile CPE 102 and the client devices 104 for achieving interactions based on the MIP. In addition, the home agent 130 allocates a sub-network of NLAs for the client devices 104. [0099] Accordingly, at step 310, the home agent 130 responds by sending the MIP register response to the foreign agent 132 to indicate that the MIP registration is successful. As explained previously, in an example, the MIP register response can be in the same format as the MIP register request. Hence, in said example, the MIP register request includes the subnet mask parameter in the subnet mask field, indicating the NLAs allocated for the client devices 104. In said example, the home agent 130 can update the subnet mask field with the subnet mask parameter indicative of the sub-network of NLAs for allocation to the client devices 104. Further, the home address field in the MIP register response is updated by the home agent 130 to include the NLA allocated to the mobile CPE 102. Further, as mentioned previously, to indicate the successful MIP registration, the home agent 130 associates, in one example, the NLAs for the client devices 104, and in another example, the subnet mask parameter, with the NLA of the home agent 130.

[00100] Further, as shown at step 312, the MIP register response along with the subnet mask parameter is sent from the foreign agent 132 to the registration module 120.

[00101] As mentioned previously, the allocation module 122 serves as the proxy IP -based server 134 and allocates the individual NLAs to the connected client devices 104 based on the subnet mask parameter. Further, the allocation module 122 can maintain a table or other appropriate record of the sub-network of NLAs allocated to the client devices 104 and the actual NLAs allocated to each of the individual client devices 104, for example, in the allocated NLA data 126. In said example, the allocated NLA data 126 can be used by the mobile CPE 102 for directly routing the data between the host devices 128 and the client devices 104.

[00102] On the other hand, in case the MIP registration at the home agent 130 is rejected and is unsuccessful, then, in an example, the home agent 130 can suspend the response to the MIP register request to the foreign agent 132. In said example, an error message can be sent to the mobile CPE 102 to indicate that the MIP registration is unsuccessful. Accordingly, the mobile CPE 102 can re-initiate the process of MIP registration and request for allocation of the sub-network of NLAs for the client devices 104 and the NLA for the mobile CPE 102.

[00103] Further, as explained previously, in case of deregistration of any one or all of the client devices 104, the sub-network of NLAs is released and communicated to the mobile CPE 102. The same released NLAs are then available for allocation by the mobile CPE 102 to other client devices connecting to the mobile CPE 102 in the communication network 108. [00104] Further, with reference to the description of figure 3 and figure 4, in the event of the mobile CPE 102 leaving the network, such an event can, in an example, lead to the whole subnetwork of NLAs for the client devices 104 and the single NLA for the mobile CPE 102 being released by the mobile CPE 102. Accordingly, the device allocating the sub-network is informed about such release so that the released sub-network can be re-allocated to another requesting set of mobile CPEs and client devices. For example, in case the sub-network is allocated by the IP- based server 134, then the registration module 120 can send a release message including the subnet mask parameter, indicating the released sub-network, to the IP -based server 134. In another example, in case the sub-network has been allocated by the home agent 130, then the registration module 120 can send an MIP deregister request having the subnet mask parameter to the home agent 130.

[00105] In addition, with reference to the description of figure 2, figure 3, and figure 4, in an implementation, the registration module 120 can be configured to deactivate default procedures, such as network address translation (NAT), which are carried out by the mobile CPE 102 in order to implement the functionalities as explained above.

[00106] Figure 4 and figure 5 illustrate methods 400 and 500 for dynamic allocation of an NLA to the client devices 104 connected to the mobile CPE 102, according to two different embodiments of the present subject matter. The order in which the methods 400 and 500 are described is not intended to be construed as a limitation, and any number of the described method blocks can be combined in any order to implement the methods 400 and 500, or alternative methods. Additionally, individual blocks may be deleted from the methods 400 and 500 without departing from the spirit and scope of the subject matter described herein. Furthermore, the methods can be implemented in any suitable hardware, software, firmware, or combination thereof.

[00107] A person skilled in the art will readily recognize that steps of the methods 400 and 500 can be performed by programmed computers. Herein, some embodiments are also intended to cover program storage devices, for example, digital data storage media, which are machine or computer readable and encode machine-executable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of the described method. The program storage devices may be, for example, digital memories, magnetic storage media such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media. The embodiments are also intended to cover both, communication network and communication devices configured to perform said steps of the methods 400 and 500.

[00108] With reference to the description of figure 4 and figure 5, for the sake of brevity, the details of the components of the various devices, such as the mobile CPE 102, for achieving dynamic allocation of NLAs for the client devices 104, are not discussed here. Such details can be understood as provided in the description provided with reference to figure 1, figure 2, and figure 3.

[00109] Referring to figure 4, the method 400 illustrates the implementation in which the allocation of NLAs to the client devices 104 is achieved by the mobile CPE 102 through the PMIP client. The mobile CPE 102 can support the plurality of client devices 104 and facilitate communication of the client devices 104 with the host devices 128 over the communication network 108. In said implementation, the capability of achieving MIP registration for allocation of NLAs is provided to the PMIP client. Accordingly, intermediary agent can include the PMIP client co-located with the relay agent 136 on the same device, and all the messages transmitted from and to the mobile CPE 102 over the communication network 108 are routed through the PMIP client. Further, as explained earlier, in this case, the procedure for obtaining the subnetwork of NLAs for the client devices 104 is carried out with the IP -based server 134.

[00110] At block 402, the allocation of NLAs for the client devices 104 is initiated by the mobile CPE 102 supporting the client devices 104 by sending a discover message to one or more IP -based servers 134. In an example, the discover message is transmitted by the mobile CPE 102 to the relay agent 136, say co-located with the PMIP client. In an example, the relay agent 136 can parse discover message and further send the discover message to the IP -based servers 134. According to an aspect, the discover message can include a subnet request option indicating that the mobile CPE 102 intends to obtain a sub-network for allocation to the client devices 104.

[00111] In an example, the PMIP client can further broadcast the message to the IP -based servers 134. In another example, the discover message can be received by a relay agent 136 of the IP -based server 134 and the relay agent 136 can direct the discover message to a single selected IP -based server 134.

[00112] At block 404, in response to the discover message, an offer message is received, say at the PMIP client, from each of one or more available IP -based servers 134. In an example, the available IP -based servers 134 can be understood as those, from among all the IP -based servers 134 to whom the discover message is broadcast, that have a sub-network of NLAs available for the client devices 104 and also have an NLA for allocation to the mobile CPE 102. In another example, as explained previously, in case the discover message is transmitted to the selected IP- based server 134, then a single offer message is received from that selected IP -based server 134, say depending on availability of the NLAs for allocation with the IP -based server 134.

[00113] According to an aspect, the offer message can include a subnet response option indicating availability of the sub-network of NLAs for allocation to the mobile CPE 102. In addition, the subnet response option can include a subnet mask parameter, inserted by the IP- based server 134 sending the offer message, and indicating the sub-network of NLAs available for allocation for the client devices 104. In an example, the subnet mask parameter can be 255.255.255.240. Additionally, in said example, based on the subnet mask parameter, the actual sub-network of NLAs can be determined, say by determining a logical AND of the NLA for allocation to the mobile CPE 102 and the subnet mask parameter. For example, if 192.168.1.1 is the NLA available for the mobile CPE and the subnet mask parameter is 255.255.255.240, then the sub-network of NLAs for the client devices 104 is depicted by 192.168.1.0/28. In said example, based on the sub-network, the actual NLAs for allocation to the client devices 104 can be determined. In an implementation, the PMIP client forwards the offer message to the mobile CPE 102. As the name suggests, the offer message can be indicative of an offer from the available IP -based servers 134 to the CPE 102 for accepting the NLAs being made available for allocation.

[00114] Once the subnet response option, also indicating a permission from the IP -based server 134 to use the subnet mask parameter for allocating the NLAs to the client devices 104, is received, the mobile CPE 102 initiates the request to the IP-based server 134. The request is sent to the IP -based server 134 as part of completion of the process of allocation of the sub-network for the client devices 104.

[00115] Accordingly, at block 406, the mobile CPE 102 generates a request message, including the subnet mask parameter and the NLA available for allocation to the mobile CPE 102, and sends the request message towards the IP -based server 134. In an implementation, the request message can be received at the PMIP client, through the relay agent 136, for forwarding to the selected IP -based server 134. In an example, the selected IP -based server 134 can be selected from among the available IP -based servers from whom the offer message is received. In another example, in which the offer message is received from the selected IP -based server 134, the request message can be directed towards that selected IP -based server 134. In an example, the presence of the subnet response option in the offer message can prompt the mobile CPE 102 to accept the offer of the sub-network of NLAs from one of IP -based servers 134, in pursuit of which, the registration module 120 can generate and send the request message, which further triggers the MIP registration.

[00116] Further, as mentioned above, the receipt of the request message triggers the PMIP client to initiate the process of MIP registration. Accordingly, at block 408, the PMIP client generates an MIP register request, for example, including the subnet mask parameter and the NLA for allocation to the mobile CPE 102 as received in the request message, and sends the MIP register request to a mobility agent for achieving the registration. In an example, the mobility agent is usually the home agent 130, except in the case of the foreign agent 132 and the PMIP client not being co-located with each other. As will be understood, in the latter case, the MIP register request received by the foreign agent 132 can also be further transmitted to the home agent 130 for the MIP registration of the mobile CPE 102.

[00117] Further, according to an implementation, the PMIP client can temporarily suspend the transmission of the request message to the IP -based server 134, till the time the MIP registration is not completed.

[00118] Further, at block 410, it is determined whether the MIP registration, say at the home agent 130, is successful or not. In an implementation, the MIP register request, received by the home agent 130 through the mobility agent, can be parsed and checked for validity. For example, the home agent 130 can determine upon parsing the MIP register request that whether the NLA available for allocation to the mobile CPE 102 and sub-network provided for the client devices 104 are accepted or not, or whether the MIP register request has correct syntax and content. In the former case, the home agent 130 can reject the MIP register request, say in case the available NLAs are blacklisted.

[00119] In case the home agent 130 determines that the MIP register request is invalid and rejects the MIP register request ('No' path from block 410), then, in an implementation, the PMIP client receives a failure response message, having a failure code therein, from the home agent 130. In such a case, at block 412, the transmission of the request message, whose transmission is temporarily suspended, is permanently stalled by the PMIP client, and the lease duration of the request message is allowed to expire. In an example, the PMIP client can wait for the response from the home agent 130 till the expiry of the lease duration of the MIP register request, and upon the expiry of the same, the PMIP client permanently suspends the sending the request message.

[00120] On the other hand, in case the MIP register request is accepted and the MIP registration is successfully achieved ('Yes' path from block 410), then at block 414, an MIP register response is received, say at the PMIP client from the home agent 130 through the mobility agent, i.e., the foreign agent 132. In an example, the MIP register response is in the same format as the MIP register request, for example, the MIP register response includes the NLA for the mobile CPE 102 and the subnet mask parameter. In addition, as part of the MIP registration, in an example, the home agent 130 determines the NLAs for allocation to the client devices 104, and associates the NLAs with the NLA of the home agent 130. In another example, the home agent 130 can associate the sub-network of NLAs for the client devices with the NLA of the home agent 130. In this case, as and when a request for connecting to the client devices 104 is received from one or more host devices 128, the home agent 130 can derive the NLAs of the client devices 104 on the fly and route the data accordingly. Additionally, the NLAs and/or the subnet mask parameter can also be associated with the NLA of the foreign agent 132, while the MIP register response is being routed back to the PMIP client.

[00121] In an implementation, with the registration of the sub-network of NLAs for the client devices 104 at the home agent 130, the allocated NLAs of the client devices 104 are not masked and are provided as publically routable NLAs. Hence, the host devices 128 can directly communicate with the individual client devices 104 based on the association, and in effect achieve direct IP routing with the individual client devices 104.

[00122] Subsequently, at block 416, upon receiving the MIP register response from the home agent 130, the PMIP client is informed that the MIP registration is successful. In response, the PMIP client transmits the temporarily suspended request message to the IP-based server 134. As mentioned previously, the request message includes the NLA available for the mobile CPE 102 and the sub-network of NLAs for the client devices 104. The request message serves as a confirmation from the mobile CPE 102 to the IP -based server for acceptability of the offer of the NLAs from the IP -based server 134. With the transmission of the request message, the mobile CPE 102 is informed that the MIP registration is complete.

[00123] Further, at block 418, after receiving the request message, the IP -based server 134 issues an acknowledgement message indicating that the NLA for the mobile CPE 102 and the sub-network of NLAs for the client devices 104 have been provided to the mobile CPE 102. The acknowledgement message can also include the lease duration for the allocation of the NLAs to the mobile CPE 102 and the client devices 104.

[00124] In addition, once the acknowledgement message is received, at block 420, the mobile CPE 102 acts as a proxy IP -based server and allocates the NLAs to the client devices, based on the subnet mask parameter and also based on the subnet response option, which permits the mobile CPE 102 to achieve the allocation. As mentioned earlier, with the registration of the NLAs at the home agent 130 and the foreign agent 132, in an example, an NLA-in-NLA tunnel, say an IP-in-IP tunnel is formed between the home agent 130, the foreign agent 132, and the mobile CPE 102, which allows the data to be directly routed between the individual client devices 104 and the host devices 128.

[00125] Figure 5 illustrates the method 500 for allocation of NLAs to the client devices 104 connected to the mobile CPE 102, according to another implementation of the present subject matter. The method 500 illustrates the implementation in which the mobile CPE 102 is configured to achieve the allocation of NLAs for the client devices 104 through the mobility agent, in tandem with the MIP registration. As has been mentioned previously, the mobile CPE 102 can support the plurality of client devices 104 and facilitate communication of the client devices 104 with the host devices 128 over the communication network. In said implementation, the capability of achieving MIP registration is provided to the mobile CPE 102, for example, to the registration module 120 of the mobile CPE 102. Accordingly, the mobile CPE 102 can communicate with the mobility agent MIP registration. Additionally, in said implementation, the mobile CPE 102 also requests the allocation of NLAs from the home agent 130, say through the mobility agent.

[00126] In said implementation, to initiate the NLA allocation as well as MIP registration, at block 502, an agent solicitation message is transmitted from the mobile CPE 102, connected to the client devices 104, to one or more mobility agents, over the communication network 108. As has been explained earlier, the mobility agent in the home network can be the home agent 130, and in the foreign network can be the foreign agent 132. In the latter case, the agent solicitation message can be broadcast in the communication network 108 to identify the mobility agent to connect to the home agent 130 catering to the mobile CPE 102.

[00127] In response to the agent solicitation message, at block 504, an agent advertisement can be received from each of one or more available mobility agents. In case the mobile CPE 102 is in the home network, the agent advertisement is received from the home agent 130. In an implementation, the agent advertisement can include a care-of-address, indicating the NLA offered for allocation to the mobile CPE 102, provided by the mobility agent from whom the agent advertisement is received. In an example, when received from the foreign agent 132, the agent advertisement can indicate availability and offer from the foreign agent 132 to facilitate communication of the mobile CPE 102 with the home agent 130. On the other hand, when received from the home agent 130, the agent advertisement can indicate an offer to allow MIP registration.

[00128] According to an aspect, the receipt of the agent advertisement can serve as a trigger for the initiation of the MIP registration process. In an implementation, the mobile CPE 102 can select one mobility agent, say the foreign agent 132 in case the mobile CPE 102 is in the foreign network, for initiating the MIP registration and NLA allocation, and can send the MIP register request to the selected mobility agent. In such a scenario, the mobility agent, i.e., the foreign agent 132, can forward the MIP register request to the home agent 130. In the other case of the mobile CPE 102 being in the home network, the mobile CPE 102 can send the MIP register request to the home agent 130 directly.

[00129] According to an implementation, the mobile CPE 102 can include a default subnet mask parameter in the MIP register request, say in the subnet mask field of the MIP register request. In an example, the default subnet mask parameter can be 0.0.0.0. According to an aspect of the present subject matter, the presence of the subnet mask parameter in the MIP register request indicates that the mobile CPE 102 is requesting allocation of the NLAs for itself and allocation of the sub-network of NLAs for the client devices 104 from the home agent 130.

[00130] Subsequently, at block 508, it is determined whether the MIP registration at the home agent 130, based on the MIP register request, is successful or not. In an implementation, upon receipt of the MIP register request, the home agent 130 can parse the MIP register request and check the same for validity, say whether the MIP register request has acceptable syntax and content or not.

[00131] In case the MIP registration is unsuccessful ('No' path from block 508), then at block 510, the MIP register request is suspended by the home agent 130, and the failure response message, having the failure code, is sent to the foreign agent 132. As a result, in an example, the MIP register request times out, and in such a case, the foreign agent 132 realizes upon the expiry of the lease duration of the MIP register request that the MIP registration has failed. Accordingly, the foreign agent 132 can send an error message to the mobile CPE 102, which can then re-initiate the process of MIP registration and the sub-network allocation, from block 502 onwards.

[00132] On the other hand, in case the MIP registration is successful, say the MIP register request is acceptable, ('Yes' path from block 508), then at block 512, an MIP register response is received from the home agent 130 to the mobile CPE 102 through the mobility agent, for example, the foreign agent 132. In an example, the MIP register response is in the same format as the MIP register request. Accordingly, in said example, the home agent 130 can populate the subnet mask field in the MIP register request and provide the actual subnet mask parameter to the mobile CPE 102 in the MIP register response, and also provide the NLA for the mobile CPE 102, say in a home address field in the MIP register response. According to an aspect, the presence of the updated subnet mask field also provides a permission to the mobile CPE 102 to further use the subnet mask parameter for allocation of the individual NLAs to the client devices 104.

[00133] In an implementation, the successful MIP registration and the receipt of the MIP register response can indicate that the sub-network for the client devices 104 has been allocated by the home agent 130 and the sub-network has also been registered at the home agent 130. Accordingly, as a part of the MIP registration, the home agent 130 can associate the NLAs for the client devices 104, the sub-network, or the subnet mask parameter, with the NLA of the home agent 130 to directly route the data between the individual client devices and the host devices 128. Additionally, the NLAs, the sub-network, or the subnet mask parameter can also be associated with the NLA of the foreign agent. As a result, a connection is established between the mobile CPE 102, the home agent 130, and the foreign agent 132, for example, in the form of a NLA-in-NLA tunnel, say an IP-in-IP tunnel, while routing data between the client devices 104 and the host devices 128. In said example, the NLA- in -NLA tunnel can be understood to include the association of the single NLA of the home agent 130 and/or the foreign agent 132, and the sub-network of NLAs of the client devices 104.

[00134] Further, at block 514, after the successful completion of the MIP registration and obtaining the NLAs for allocation, the mobile CPE 102 can allocate the individual NLAs to the client devices 104 based on the subnet mask parameter in the MIP register response. In said implementation, the mobile CPE 102 can function as a proxy IP -based server and achieve the allocation of the NLAs to the individual client devices 104, say based on DHCP procedures for NLA allocation.

[00135] In both the above implementations, in the event of change of location of the mobile CPE 102, the mobile CPE 102 again triggers the initiation of the MIP registration process with another mobility agent, in case the mobile CPE 102 has changed location to a new foreign network. Accordingly, the mobile CPE 102 and the connected client devices 104 are provided with seamless connectivity with the host devices over the communication network 108.

[00136] Although implementations for dynamic allocation of NLAs to client devices 104 connected to the mobile CPE 102 have been described in language specific to structural features and/or methods, it is to be understood that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as implementations for dynamic allocation of NLAs to client devices 104 connected to the mobile CPE 102.

Claims

I/We claim:

1. A method for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices (104) connected to a mobile consumer premises equipment (CPE) (102), the method comprising:

initiating registration of available sub-network of NLAs for allocation to the client devices (104), based on one of receipt of a subnet response option in an offer message and transmission of a default subnet mask parameter in a mobile internet protocol (MIP) register request;

receiving a confirmation for allocation of the available sub-network of NLAs for the client devices (104); and

allocating available NLAs to the plurality of client devices (104), based on the available sub-network of NLAs.

2. The method as claimed in any one of the preceding claims, wherein the registration comprises associating the available NLAs for allocation to the plurality of client devices (104) with an NLA of at least a home agent (130) catering to the mobile CPE (102).

3. The method as claimed in any one of the preceding claims, wherein the initiating the registration of the available sub-network of NLAs for allocation to the client devices (104), based on the receipt of the subnet response option in the offer message, comprises:

sending a discover message to at least one IP -based server (134), wherein the discover message comprises a subnet request option;

receiving the offer message from the at least one IP -based server (134), in response to the discover message, the offer message comprising,

the subnet response option indicating availability of sub-network of NLAs for allocation to the plurality of client devices (104);

a subnet mask parameter indicating the available sub-network of NLAs for determining the available NLAs; and

an NLA for allocation to the mobile CPE (102); and sending a request message indicating acceptance of the available sub-network NLAs for allocation to the plurality of client devices (104) and the NLA available for the mobile CPE (102).

The method as claimed in claim 1 or 2, wherein the initiating registration of the available sub-network of NLAs for allocation to the client devices (104) based on the transmission of the default subnet mask parameter in the MIP register request comprises:

sending an agent solicitation message to initiate connection with a mobility agent; and obtaining an agent advertisement, in response to the agent solicitation message, the agent advertisement indicating establishment of connection with the mobility agent for achieving the registration.

The method as claimed in claim 4, wherein the initiating comprises:

sending a mobile internet protocol (MIP) register request comprising a default subnet mask parameter indicating request for allocation of at least the available sub-network of NLAs for the client devices (104); and

obtaining an MIP register response, in response to the MIP register request, wherein the MIP register response comprises the NLA for allocation to the mobile CPE (102) and the subnet mask parameter for determining the available sub-network of NLAs for allocation to the plurality of client devices (104).

A mobile Consumer Premise Equipment (CPE) (102) for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices (104) supported by the mobile CPE (102), the mobile CPE (102) comprising:

a processor (110); and

a memory (1 12) coupled to the processor (110), the memory (112) comprising, a registration module (120) configured to,

transmit an MIP register request for achieving MIP registration of the mobile CPE (102), wherein the MIP register request comprises a default subnet mask parameter indicative of a request for allocation of an available subnetwork of NLAs for the plurality of client devices (104); and obtain, in response to the MIP register request, an MIP register response comprising a subnet mask parameter for determining the available sub-network of NLAs for allocation to the client devices (104), wherein the MIP register response indicates association of the available sub-network of NLAs for allocation to the client devices (104) with at least an NLA of a home agent (130) catering to the mobile CPE (102).

The mobile CPE (102) as claimed in any one of the preceding claims, wherein the registration module (120) is further configured to:

transmit an agent solicitation message to initiate connection with a mobility agent catering to the mobile CPE (102); and

obtain an agent advertisement, in response to the agent solicitation message, the agent advertisement indicating establishment of connection with the mobility agent for achieving the registering.

The mobile CPE (102) as claimed in any one of the preceding claims, further comprising an allocation module (122) configured to allocate the NLAs to the plurality of client devices (104), based on the MIP register response.

a processor (110); and

a memory (1 12) coupled to the processor (110), the memory (112) comprising,

a registration module (120) configured to,

transmit a discover message to at least one IP-based server (134), the discover message comprising a subnet request option indicative of a request to allocate an available sub-network of NLAs for the plurality of client devices (104);

obtain, in response to the discover message, an offer message from the at least one IP -based server (134), the offer message comprising, a subnet response option indicating availability of the NLAs for allocation to the plurality of client devices (104); and

a subnet mask parameter for determining the available sub-network of NLAs for allocation the client devices (104); and providing, in response to the offer message, a request message for registration of the available sub-network of NLAs.

10. The mobile CPE (102) as claimed in claim 9, further comprising an allocation module (122) configured to allocate the NLAs to the plurality of client devices (104), based on the available sub-network of NLAs.

1 1. A proxy mobile internet protocol (PMIP) client for achieving dynamic allocation of network layer addresses (NLAs) to a plurality of client devices (104) connected to a mobile consumer premises equipment (CPE) (102), the PMIP client configured to:

transmit an MIP register request for achieving the MIP registration, the transmission being triggered by the mobile CPE (102), wherein the MIP register request comprises available sub-network of NLAs for allocation to the client devices ( 104) determined based on a subnet response option; and

obtain an MIP register response, in response to the MIP register request, wherein the MIP register response is indicative of association of available NLAs for allocation to the client devices (104), determined based on the available sub-network of NLAs, with at least an NLA of a home agent (130).

12. An IP -based server (134) for achieving dynamic allocation of a network layer address (NLA) to each of a plurality of client devices (104) connected to a mobile CPE (102), the IP -based server (134) configured to:

receive a discover message from the mobile CPE (102), the discover message comprising a subnet request option indicating a request to allocate a sub-network of NLAs for the plurality of client devices (104); and

transmit, based on the discover message, an offer message to the mobile CPE (102), the offer message comprising, a subnet response option indicating availability of the sub-network NLAs for allocation to the plurality of client devices (104); and

a subnet mask parameter for determining the sub-network of NLAs for allocation the client devices (104).

13. A home agent (130) for achieving dynamic allocation of network layer addresses (NLAs) to a plurality of client devices (104) connected to a mobile CPE (102), the home agent (130) configured to:

receive a mobile internet protocol (MIP) register request for MIP registration;

perform the MIP registration in response to the MIP register request; and

transmit, based on the MIP register request, an MIP register response confirming the achieving the MIP registration of available sub-network of NLAs for allocation to the client devices (104).

14. The home agent (130) as claimed in any one of the preceding claims, further configured to include a subnet mask parameter in the MIP register response, the subnet mask parameter indicative of the available NLAs for allocation to the plurality of client devices (104).

15. A computer-readable medium having embodied thereon a computer program for executing a method for dynamic allocation of network layer addresses (NLAs) to a plurality of client devices (104) connected to a mobile consumer premises equipment (CPE) (102), the method comprising:

initiating mobile internet protocol (MIP) registration of the mobile CPE (102), based on one of receipt of a subnet response option and receipt of an agent advertisement;

receiving, in response to the MIP register request, an MIP register response comprising a subnet mask parameter for determining available NLAs for allocation to the plurality of client devices (104), wherein the MIP register response indicates registration of the available NLAs for allocation to the plurality of client devices (104).