JP3916542B2 - Address assignment system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an address assignment system, and is suitable for application to a system using a DHCP server, for example.
[0002]
[Prior art]
The DHCP server originally determines and secures an IP address to be assigned to a terminal when an IP address acquisition request is received from a terminal having a MAC address, and manages the MAC address of the terminal and the assigned IP address in association with each other.
When this terminal is a TA 13 for VoIP (Voice ovre IP), the schematic configuration of the system 10 in the VoIP network including this is as shown in FIG. 6, and the operations of the provisioning system 11 and the DHCP server 15 in this system 10 are as follows. As shown in FIG.
[0003]
In the provisioning of the VoIP service, as shown in FIG. 2, when the provisioning system 11 transmits an IP address acquisition request to the DHCP server 15 in response to a request from the VoIP TA 13 (S11, S1), the DHCP server 15 The MAC address received with the acquisition request is stored in the address management table TB1 in association with the IP address secured (assigned) according to the acquisition request, and then the secured IP address is returned (S12, S1). Upon receiving this, the provisioning system 11 notifies the VoIP system 12 of the correspondence between the acquired IP address and the MAC address (S2).
[0004]
An IP address is set in the VoIP TA 13 based on the information.
[0005]
The IP address acquired at this time is an arbitrary IP address that has not been used at the time when the acquisition request is issued among the plurality of IP addresses prepared by the DHCP server 15. Therefore, the IP address set in the same VoIP TA (for example, 13) can be changed every time a new acquisition request is issued.
[0006]
Since a plurality of terminals similar to the VoIP TA 13 can be provided under the VoIP system 12, the same processing is performed in response to requests from these terminals as shown in steps S13 and S14 in FIG. Repeated several times.
[0007]
[Problems to be solved by the invention]
However, when such an address allocation method is used, when there are a plurality of systems that transmit acquisition requests to the DHCP server 15 as in the systems 10 and 20 of FIG. Since the IP address is acquired, the IP address may not be assigned according to the acquisition request, and the system availability is low.
[0008]
The process in this case is, for example, a procedure as shown in steps S15 to S18 in FIG.
[0009]
In FIG. 4, the DHCP server 15 prepares IP addresses for 254 hosts as IP addresses to be allocated in response to the acquisition request. However, 254 acquisition requests from the system 20 (shown as one step S15). ), After assigning 254 IP addresses (S16), even if an acquisition request is received from the system 10 (S17), there are no unused IP addresses that can already be assigned. It is notified that the address does not exist (S18).
[0010]
The assigned IP address is also returned and returned to an unused state when communication using the IP address is completed, so that the DHCP server 15 can respond to an acquisition request from the system 10 after the return. However, during the period until the return is made, the telephone 14 using VoIP cannot make or receive a call, for example, and when making or receiving a call for an urgent conversation, etc. This is extremely inconvenient.
[0011]
In this case, if the other system is also a system that supports VoIP communication similar to the system 10 that supports VoIP, the number of IP addresses prepared by the DHCP server 15 is eventually compared with the number of hosts and the frequency of communication. This results in a problem of lack, but is appropriate when the other system 20 is compatible with an application (for example, FTP) that does not require real-time performance such as VoIP communication. By taking measures, there is a possibility that the availability of real-time communication can be increased flexibly.
[0012]
Here, real-time communication refers to communication in which immediacy is required for a call or a response, such as an IP phone.
[0013]
On the other hand, in the address assignment method as shown in FIG. 2, since an unused IP address is assigned when an acquisition request is issued, for example, as shown in FIG. 5, the VoIP system 12 has a plurality of VoIP under its control. When a plurality of IP addresses are acquired for the TA (one of which is 13), the IP addresses have discontinuous values, and address management in the VoIP system 12 becomes complicated and inefficient.
[0014]
Similarly, address management in the DHCP server 15 or the like becomes complicated.
[0015]
In FIG. 5, the DHCP server 15 repeats the operation of assigning one larger IP address in the order in which the acquisition requests are received. After the system 10 acquires the IP address in steps S20 and S21, the DHCP server 15 in steps S22 and S23. Since the system 20 has acquired the IP address, the value of the IP address acquired by the system 10 in steps S24 and S25 is a value consecutive to the value acquired in steps S20 and S21 (that is, the IP address acquired last time). The value obtained by +1 or -1).
[0016]
[Means for Solving the Problems]
In order to solve such a problem, in the present invention, every time an allocation request is received from a communication terminal existing within a predetermined management range, an address selected from unallocated addresses among the addresses stored by itself In an address allocation system having a dynamic address allocation server that dynamically allocates (1) Providing an address assignment relay system interposed between the dynamic address assignment server and a plurality of communication terminals; Said The address assignment relay system For each of the plurality of communication terminals, before each communication terminal actually transmits an allocation request, a plurality of addresses including a temporary request source address as a request source address are continuously transmitted to the dynamic address allocation server. (2) When the dynamic address allocation server receives the continuous allocation request from the address allocation relay system, (2) the dynamic address allocation server stores it. A predetermined number of consecutive addresses from among the unassigned addresses are reserved, and the provisional request source address is associated with the predetermined number of reserved addresses to manage that they are reserved ( 2-2) The relay target by the address assignment relay system When the communication terminal transmits an allocation request, among the predetermined number of secured addresses, one address associated with the temporary request source address is allocated, and the temporary request source is assigned to the allocated address. Corresponding to the request source address related to the communication terminal of the current request source instead of the address It is characterized by that.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
(A) Embodiment
Hereinafter, an address assignment system according to the present invention is referred to as ITU-T Recommendation H.264. The embodiment will be described by taking as an example a case where the present invention is applied to a VoIP network that performs VoIP in an environment conforming to H.323.
[0018]
(A-1) Configuration of the embodiment
FIG. 8 shows an example of the entire configuration of the VoIP network 30 (including a detailed configuration example of the constituent elements) of the present embodiment.
[0019]
In FIG. 8, the VoIP network 30 includes an IP network 31 and four bases 32 to 35 connected by the IP network 31.
[0020]
Of these, the IP network 31 can be replaced by the Internet or the like, but here, it is assumed that the IP network is constructed and operated by a specific communication carrier and provided to the user. Such an IP network is the same as the Internet in that communication using the IP protocol is performed, but is different in that communication quality can be guaranteed according to facilities prepared by a communication carrier.
[0021]
The IP network 31 may be constructed by the user company itself so that it can be used by its own employees. In general, the network 31 is shared by a plurality of user companies, and a VoIP service is provided to each user company. In this case, an IP-VPN is often used so that one company can connect between the bases while maintaining confidentiality.
[0022]
The IP network 31 can be connected to the Internet or an existing subscriber telephone network as required.
[0023]
The bases 32 to 35 shown in FIG. 8 may be a LAN (local area network) corresponding to a sales office, branch office, head office, etc. of one company among a plurality of user companies sharing the IP network 31. .
[0024]
There can be various network configurations in the LANs 32 to 35. In practice, the network configuration is often different between the head office, branch offices, and sales offices, but at least the provisioning system 41, the DHCP server 42, and the VoIP system. Since it may be the same in that the main components such as 45 are provided, the network configuration of all the bases 32 to 35 will be described as being substantially the same regardless of the details.
[0025]
Among such bases 32 to 35, the constituent elements of the base 35 may be as shown in FIG. 7, for example, but FIG. 8 shows a more detailed configuration example of the base 35.
[0026]
That is, the base 35 includes a router 40, the provisioning system 41, a DHCP server 42, personal computers 43 and 44 (corresponding to the other system 70 in FIG. 7), a VoIP system 45, VoIP TAs 46A to 46N, Telephones 47A to 47N.
[0027]
Of these, the router 40 is a device that connects the transmission line L 1 in the base 35 to the IP network 31.
[0028]
Here, it is assumed that the router 40 has only the port P1 on the IP network 31 side and the port P2 on the transmission line L1 side. However, if the router 40 has a port other than the port P2 on the inner side of the base 35, the provisioning system 41 is provided. Of course, the DHCP server 42, the personal computers 43 and 44, and the VoIP system 45 may be connected to different ports.
[0029]
When the IP-VPN is used, the encryption and decryption functions necessary for the IP-VPN may be installed in the router 40.
[0030]
A gatekeeper function or the like can also be mounted on the router 40.
[0031]
A gatekeeper is a type of server that manages the correspondence between telephone numbers and IP addresses, and has a function of returning an IP address in response to an inquiry from a VoIP TA (for example, 46A). When making a call, the telephone user (for example, U3) inputs only the telephone number of the communication partner to the telephone (for example, 47N), but communicates on the IP network 31 that performs communication according to the IP protocol. Since the only identifier effective for identifying the other party is an IP address, it is necessary to inquire the gatekeeper and obtain an IP address corresponding to the telephone number.
[0032]
The personal computers 43 and 44 are ordinary personal computers equipped with a network function, but may be equipped with an FTP client function, a video conference system function, or the like. If a microphone, a speaker, etc. are equipped and software as an IP telephone is installed, the personal computers 43 and 44 can be used as an IP telephone.
[0033]
However, in this embodiment, in order to clarify the comparison with the above-described VoIP TAs 46A to 46N that perform real-time communication, the personal computers 43 and 44 have a function as an FTP client that performs FTP communication or the like, which is not real-time communication. Assume a case.
[0034]
The personal computer 43 is operated by the user U4, and the personal computer 44 is operated by the user U5.
[0035]
Since the DHCP server 42 is provided with global IP addresses for 254 hosts, which will be described later, the number of hosts in the base 35 is usually less than 254. May be on the order of hundreds or more.
[0036]
The VoIP system 45 accommodates general telephones 47A to 46N via VoIP TAs 46A to 46N, and is similar to PBX (private branch exchange) or a telephone exchange on the public telephone network for voice communication using VoIP. It is a system that provides
[0037]
Therefore, when an IP address is assigned to the VoIP TA (for example, 46A) from the DHCP server 42, the VoIP system 45 receives the IP address and the VoIP TA (in this case, 46A) via the provisioning system 41. The MAC address correspondence relationship is notified. The VoIP system 45 may be installed in the base 35 by the communication carrier.
[0038]
The VoIP TAs 46A to 47N are terminal adapters equipped with a call control function, a codec function, a VoIP function, and the like. Since the VoIP function is provided, the VoIP TAs 46A to 46N can be regarded as a kind of VoIP gateway.
[0039]
In addition, a DHCP client function for transmitting an acquisition request to the DHCP server 42 as necessary may be installed in the VoIP TAs 46A to 47N.
[0040]
Here, general telephones 47A to 47N are connected, but the VoIP TA can also connect a G3 facsimile, a personal computer, etc. to the IP network, and can realize IP integration at a relatively low cost. is there.
[0041]
The VoIP TA 46A functions for the general telephone 47A, the VoIP TA 46B functions for the general telephone 47B,..., And the VoIP TA 46N functions for the general telephone 47N.
[0042]
The general telephones 47A to 47N are normal telephones that are not equipped with the VoIP function and are not compatible with VoIP.
[0043]
A so-called IP telephone can be regarded as a communication apparatus provided with the function of a general telephone and the function of VoIP TA in one apparatus in principle.
[0044]
Therefore, the VoIP system 45 can accommodate IP telephones as necessary.
[0045]
The general telephone 47A is operated by the user U1, the general telephone 47B is operated by the user U2,..., And the general telephone 47N is operated by the user U3.
[0046]
The DHCP server 42 is a server that assigns an IP address in response to an acquisition request from the VoIP TAs 46A to 46N, the personal computers 43 and 44, and the like.
[0047]
In many cases, the DHCP server assigns a private IP address that is unique only within the LAN under the condition of using NAT together. However, the DHCP server 42 of this embodiment assigns a global IP address. The global IP address is guaranteed to be unique globally (thus, of course, uniqueness is also guaranteed within the LAN), but is currently feared to be exhausted.
[0048]
As a call control protocol, ITU-T recommendation H.264 is used. An IP phone using H.323 or SIP is one of applications that make it difficult to perform normal communication via NAT (or IP masquerade).
[0049]
The cause is mainly that the transmission IP address (private IP address) and port number are stored in the data part (payload part) of the IP packet and transmitted, and the transmission source IP address extracted from the data part by the communication partner The destination IP address is used to send back a return IP packet, and even if NAT (or IP masquerading) converts the source IP address in the header part, the data is sent to the source IP address in the data part. By not converting. This is because the private IP address cannot function as a valid identifier outside the LAN.
[0050]
As countermeasures, it is effective to use a global IP address without using a private IP address in the LAN (and therefore, do not use NAT) or use a so-called NAT traversal.
[0051]
If a global IP address is used in the LAN, problems such as the fact that the structure in the LAN is easily known from the outside and the security is lowered, or it is difficult to prepare a sufficient number of global IP addresses may occur. There is no need to add special functions, and communication can be performed by simple processing.
[0052]
On the other hand, in NAT traversal, since NAT is used and the IP address (global IP address) on the port P1 side of the router 40 is stored as the source IP address stored in the data part, the security is not lowered. There is no shortage of global IP addresses. However, processing to notify the IP address (global IP address) on the port P1 side of the router 40 to the VoIP TA (for example, 46A) or the like is necessary as needed, and such notification is requested or notified. Therefore, the router 40, the TAs 46A to 46N for VoIP, the personal computers 43 and 44, and the like are required to be compatible with NAT traversal, and a lot of cost and labor are often required for realization.
[0053]
The present embodiment is applicable to any of these cases.
[0054]
When a global IP address is used instead of a private IP address in the LAN (base 35), each terminal (for example, VoIP TA 46A) uses the global IP address assigned by the DHCP server 42 as its own source IP address. This is because, when using NAT traversal, the global IP address of the port P1 notified from the router 40 should correspond to the global IP address assigned by the DHCP server 42.
[0055]
The DHCP server 42 is a server that automates the setting of various setting information (including an IP address) related to TCP / IP and dynamically sets it when necessary. Accordingly, the setting information set by the DHCP server includes information other than the IP address, such as a subnet mask and a default gateway. Here, attention is paid to the IP address. By using the DHCP server 42, compared to the case where setting information is manually set in each terminal, the workload related to setting is reduced, troubles caused by setting mistakes are prevented, and the use efficiency of IP addresses is improved (between a large number of hosts). Thus, an effect such as sharing a small number of IP addresses can be obtained.
[0056]
The DHCP server 42 has an internal configuration as shown in FIG. Although the function of the DHCP server can be implemented by software in the router 40, for example, the DHCP server 42 of the present embodiment is an independent machine.
[0057]
(A-1-1) Internal configuration example of DHCP server
In FIG. 9, the DHCP server 42 includes a communication unit 50, a control unit 51, an address management unit 52, and a range (RANGE) correspondence unit 53.
[0058]
Among these, the communication part 50 is a part which communicates with each component 41,43,44 etc. in the base 35 via the said transmission line L1.
[0059]
The control unit 51 is a central processing unit (CPU) of the DHCP server 42 in terms of hardware, and an operating system (OS) in terms of software.
[0060]
The address management unit 52 manages a predetermined address management table TB2 and constitutes a kind of database.
[0061]
As shown in FIG. 1, the address management table TB2 is a table having an IP address and a MAC address as column names (data items), and manages the correspondence between the IP address and the MAC address. An IP address for which the corresponding MAC address is a null value is an unused IP address.
[0062]
In FIG. 1, the address management table TB2 stores IP addresses in dot notation. The smaller IP addresses are arranged in the upper row, and the values of the IP addresses adjacent to each other in the vertical direction (differ by 1). ) Is continuous.
[0063]
That is, “1.1.1.1” is arranged in the top row, “1.1.1.2” is arranged in the second row from the top, and the third row from the top is arranged. “1.1.1.3” is arranged, and the values are consecutive as shown in FIG.
[0064]
Such a continuous value can be stored in the address management table TB2 on the premise that the user company or the communication carrier manages the value of the value from the organization (registry etc.) that manages the distribution of the global IP address. This means that a continuous set of IP addresses (address block) has been distributed.
[0065]
Aside from what has been distributed in the past, the IP address depletion problem has become serious now, and a large address block (for example, an address block containing 256 (254 hosts) consecutive IP addresses) from the registry (this is (Corresponding to class C)) is not distributed, and CIDR only distributes a small address block including at most about 10 consecutive IP addresses (even in that case) From the above, it is possible to secure a range block, which will be described later), but when the communication carrier operating the IP network 31 has received distribution of a large address block (for example, class A or class B) in the past. Selects a large address block including, for example, 256 IP addresses from among the address blocks. It is possible that can be redistributed to a user.
[0066]
In addition, from the viewpoint of simplifying route information managed by a router (not shown) such as the IP network 31, even if the number is about 10 or less, IP addresses having continuous values are not distributed but distributed. There is a high possibility of being done.
[0067]
Each time the DHCP server 42 assigns an IP address in response to an IP address acquisition request, the address management unit 52 sends the acquisition request transmission source terminal (for example, 46A or 43) to the assigned IP address. The MAC address is stored in association with each other. Here, as an example, assignment is performed in ascending order of IP address values.
[0068]
For example, when an inquiry about an IP address corresponding to a certain MAC address occurs in the base 35 according to the ARP protocol (or vice versa), the content of the address management table TB2 is used as a reference. Can respond.
[0069]
The range corresponding unit 53 is a part that secures IP addresses having continuous values on the address management table TB2, and functions for the VoIP TAs 46A to 46N.
[0070]
In response to a request from the provisioning system 41, the range corresponding unit 53 is a part that secures a continuous predetermined range (range) of address blocks (range blocks) for the VoIP TAs 46A to 46N.
[0071]
Among the acquisition requests transmitted from various components in the base 35, various methods can be used as to how to identify a signal requesting to secure a range block. If the original MAC address is a predetermined value (corresponding to the temporary MAC address), it is determined that the request is for obtaining a range block.
[0072]
The range corresponding unit 53 also performs this determination.
[0073]
Various methods can be used to make the number of IP addresses included in the range block variable or fixed. Here, it is assumed that the number is variable and set to five as an example. .
[0074]
This value (here, 5) can be changed with the number of TAs 46A to 46N for VoIP as an upper limit. If the usage frequency (operating rate) of the general telephones 47A to 47N is high, the upper limit value may be set. If it is low, a value smaller than the upper limit value, for example, half of the number of VoIP TAs 46A to 46N, or 3 minutes It may be set to 1 or the like.
[0075]
In addition, the network configuration may be changed, and general telephones may be added or deleted, but such a case is also a factor for changing this value (here, five).
[0076]
This value is a payload portion of an IP packet encapsulated in a MAC frame (transmitted for the acquisition request or the like) in which a later-described temporary MAC address is a transmission source MAC address and a destination MAC address is a DHCP server 42 It is a good idea to describe in.
[0077]
Since the range block is a continuous value, in most cases, it is sufficient to manage at most about 1 byte at the right end of the 32-bit IPv4 address, and the management in the DHCP server and the VoIP system should be performed efficiently. Can do.
[0078]
Specifically, in the range block of 1.1.1.1 to 1.1.1.5, the change width of 1 byte at the right end is displayed in decimal number, 1 to 5 (that is, in binary number display, Therefore, if only the change of 3 bits located at the right end is managed among the 1 byte at the right end, the entire range block can be managed without contradiction.
[0079]
With such management, the larger the range block, the higher the efficiency.
[0080]
On the other hand, the provisioning system 41 is a device installed in the base 35 by the telecommunications carrier in order to give flexibility to the network, and a configuration example of a main part thereof is shown in FIG.
[0081]
(A-1-3) Configuration example of provisioning system
In FIG. 10, the provisioning system 41 includes a communication unit 60, a control unit 61, a reservation handling unit 62, and a temporary MAC address generation unit 63.
[0082]
Among these, the communication unit 60 corresponds to the communication unit 50, and the control unit 61 corresponds to the control unit 51, and thus detailed description thereof is omitted.
[0083]
The temporary MAC address generation unit 63 is a part that generates the temporary MAC address described above.
[0084]
The temporary MAC address is basically a fictitious MAC address, but various methods can be used to determine the value. The MAC address is 48-bit data determined by each manufacturer at the manufacturing stage of a LAN card or the like, and is used as an identifier of the data link layer of the OSI reference model. Originally, the uniqueness is guaranteed, and various communication systems are built on the assumption that the uniqueness of the MAC address is guaranteed. Therefore, the uniqueness is lost due to the generation of the temporary MAC address. Is not preferred.
[0085]
Therefore, before generating the temporary MAC address, the temporary MAC address generation unit 63 confirms that there is no terminal having the same MAC address in the base 35 and generates the temporary MAC address. Is desirable.
[0086]
If possible, the actual MAC address of the communication unit 60 of the provisioning system 41 (the part of the communication unit 60 corresponding to the LAN card (corresponding to the protocol below the data link layer of the OSI reference model)) You may make it utilize as a MAC address.
[0087]
The operation of the present embodiment having the above configuration will be described below with reference to the sequence diagram of FIG.
[0088]
The sequence diagram of FIG. 1 is composed of steps S30 to S38.
[0089]
(A-2) Operation of the embodiment
In step S <b> 30, the provisioning system 41 transmits a MAC frame having the temporary MAC address as a transmission source MAC address, thereby issuing a range block acquisition request to the DHCP server 42.
[0090]
The range block acquisition request is equivalent to collectively reserving IP addresses to be assigned one by one on a first-come-first-served basis every time the DHCP server 15 receives the acquisition request. This reservation is performed for TAs 46A to 46N for VoIP.
[0091]
At this time, if there are no consecutive unused (unassigned) IP addresses for the fixed value (5) on the address management table TB2, the DHCP server 42 notifies that the range cannot be set. In response to this notification, the provisioning system 41 periodically transmits a range block acquisition request, for example.
[0092]
Normally, the IP address assigned from the DHCP server 15 is also collected once communication with the assigned terminal (for example, the personal computer 43) is completed and returned to an unused state. The response (S31) indicating that the range has been set is returned from the DHCP server 42 to the provisioning system 41.
[0093]
The range block acquisition request by the provisioning system 41 is executed by the function of the provisioning system 41 regardless of whether the acquisition request is issued from the VoIP TAs 46A to 46N.
[0094]
In FIG. 1, after receiving the range setting response in step S31, step S32 for actually instructing static reservation (reservation) is performed. However, steps S31 and S32 can be combined into one step. .
[0095]
In any case, when the range block can be secured (reserved), the value of the temporary MAC address is stored as the MAC address of the address management table TB2, as shown in FIG.
[0096]
In the example of FIG. 1, five consecutive IP addresses (1.1.1.1 to 1.1.1.5) are reserved as range blocks.
[0097]
Thereafter, even if the personal computer 43 or the like transmits an acquisition request, the DHCP server 42 assigns an IP address in a range other than the range block (for example, 1.1.1.6) and the IP in the range block. No address is assigned.
[0098]
After the range block is reserved, one of the VoIP TAs (eg, 46A) actually sends its own MAC address (here, “AA-AA-AA-AA-AA-01”) as the source MAC. When an acquisition request is issued by transmitting a MAC frame as an address to the VoIP system 45 or the provisioning system 41, the provisioning system 41 relays the acquisition request to the DHCP server 42 (S33), and the reserved range block An arbitrary IP address is assigned from among the above.
[0099]
Here, since the DHCP server 42 allocates from a small value on a first-come-first-served basis, the “1.1.1.1” is allocated to the VoIP TA 46A that first issued an acquisition request after the reservation. It has been.
[0100]
The assigned IP address value and the correspondence between the IP address value and the MAC address are returned from the DHCP server 42 to the provisioning system 41 (S34).
[0101]
In the example of FIG. 1, the acquisition request from the personal computer 43 or the like is generated after step S34 (S35). In response to this acquisition request, the DHCP server 42 assigns an IP address other than the range block. (S36).
[0102]
Thereafter, when an acquisition request is issued from any one of the TAs for VoIP TAs 46B to 46N and relayed by the provisioning system 41, the IP address from the range block as in the case of the VoIP TA 46A. Are assigned (S37, 38).
[0103]
Thereafter, the same operation is repeated.
[0104]
(A-3) Effects of the embodiment
According to the present embodiment, flexibility is increased by the function of the provisioning system (41), and a limited global IP address can be reserved for VoIP TAs (46A to 46N) that perform real-time communication. The availability of TA for VoIP increases.
[0105]
In addition, since the range block is a continuous value, address management in a DHCP server or a VoIP system can be performed efficiently.
[0106]
(B) Other embodiments
The IP phone (a set of a general telephone and a VoIP TA) in the above embodiment can be replaced with various types of communication terminals (applications) for real-time communication such as network games and video conference systems.
[0107]
In the above-described embodiment, the provisioning system 41 and the DHCP server 42 are dedicated machines. However, these functions are realized by software, and other components (for example, the router 40) in the base 35 are implemented. It can also be implemented.
[0108]
In the above description, the present invention is realized mainly by hardware, but the present invention can also be realized by software.
[0109]
【The invention's effect】
As described above, according to the present invention, flexibility can be increased and the availability of the communication terminal can be improved.
[0110]
In the present invention, it is also possible to improve the efficiency of address management.
[Brief description of the drawings]
FIG. 1 is a sequence diagram showing an operation of a main part of a VoIP network according to an embodiment.
FIG. 2 is a sequence diagram showing an operation of a main part of a conventional VoIP network.
FIG. 3 is a schematic diagram showing a configuration example of a main part of a VoIP network for explaining a problem to be solved by the invention.
FIG. 4 is a sequence diagram showing an operation of a main part of the VoIP network for explaining a problem to be solved by the invention.
FIG. 5 is a sequence diagram showing an operation of a main part of the VoIP network for explaining a problem to be solved by the invention.
FIG. 6 is a schematic diagram showing a configuration example of a main part of a VoIP network for explaining a problem to be solved by the invention.
FIG. 7 is a schematic diagram illustrating a configuration example of a main part of the VoIP network according to the embodiment.
FIG. 8 is a schematic diagram showing an example of a connection relationship of main parts of the VoIP network according to the embodiment.
FIG. 9 is a schematic diagram illustrating a configuration example of a main part of a DHCP server used in the VoIP network according to the embodiment.
FIG. 10 is a schematic diagram illustrating a configuration example of a main part of a provisioning system used in the VoIP network according to the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11, 41 ... Provisioning system, 12, 45 ... VoIP system, 13, 46A-46N ... TA for VoIP, 14, 47A-47N ... General telephone, 15, 41 ... DHCP server, 30 ... VoIP network, 31 ... IP network, 32 to 35 ... LAN, 40 ... router, 52 ... address management unit, 53 ... range correspondence unit, 62 ... reservation correspondence unit, 63 ... temporary MAC address generation unit.

Claims (2)

A dynamic address allocation server that dynamically allocates an address selected from unallocated addresses among the addresses stored by itself every time an allocation request is received from a communication terminal existing within a predetermined management range In the address assignment system,
Providing an address assignment relay system interposed between the dynamic address assignment server and a plurality of communication terminals;
The address assignment relay system includes a provisional request source address as a request source address to the dynamic address assignment server before each communication terminal actually transmits an assignment request for the plurality of communication terminals. Send a continuous allocation request to secure an address block that has multiple addresses continuously,
The dynamic address allocation server
Upon receiving the continuous allocation request from the address allocation relay system, a predetermined number of continuous addresses are secured from among the unallocated addresses among the addresses stored by the address allocation relay system, and the predetermined number of secured addresses are Manage the reserved by associating the temporary request source address,
When the communication terminal to be relayed by the address assignment relay system has sent an assignment request, among the predetermined number of reserved addresses, assign one address associated with the temporary request source address, An address assignment system characterized in that , instead of the temporary request source address, the request source address related to the communication terminal of the current request source is associated with the assigned address. The address assignment system according to claim 1,
The continuous allocation request includes a predetermined number of information for requesting address allocation.

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