CN1630238A - Plug and play network device and its operation method - Google Patents

Abstract

A plug-and-play network device and its operation method, the network device has two network ports connected in series in any LAN with a pair of external routers, the network device is a bridge conforming to 802.11d, in which a specific IP address not belonging to the same network segment with the serial LAN is preset, but any user end in LAN can be directly connected with the network device without changing any setting, when the user connects with the network device of the specific IP, the network packet is transferred to the external router, because the network device is connected in series with the necessary path of the network signal connected with the external router, all packets to be transmitted to the specific IP can be intercepted, the MAC address of the user end is obtained and recorded, and the intercepted information packet is automatically responded, before the information packet is sent in response, the recorded MAC address of the user end replaces the MAC address of the receiving end of the information packet, and then the information packet is sent out, so that the network device achieves the effect of plug and play.

Description

Plug and play network device and its operation method

technical field

The invention relates to a plug-and-play network device, in particular to a plug-and-play network device which can be directly connected to a network without network-related settings and its operating method.

Background technique

As shown in Figure 1, in the past, a network device 4 (such as firewall, bandwidth manager, load balancing device, router and other network gateway devices) was set up on a local area network (LAN: Local Area Network) and connected through the network , must first carry out some presettings to the network device 4, for example, change the network protocol (IP: Internet Protocol) address (such as 192.168.168.100) and IP shielding (Mask) (such as 255.255.255.0) of the network device 4, And the gateway (gateway address) (eg 192.168.168.254) and domain name server (DNS: Domin Name Server) related settings of the default router (router) 5, so that it is consistent with the network segment address of the LAN (192.168.168.x) Similarly, the installation of the network device 4 is considered complete.

However, the above-mentioned various complicated settings of setting up network devices on the network usually need to be carried out through a terminal platform (console) connected to the network device or a Dynamic Host Configuration Protocol (DHCP: Dynamic Host configuration Protocol) in actual operation. In addition to burdening the internal management information service (MIS: Management Information Service) personnel or network administrators of the enterprise, for ordinary users who are not familiar with Internet related technologies, they need to set up their own on the network. Server or website is nothing less than a difficult challenge.

Contents of the invention

The purpose of the present invention is to provide a plug-and-play network device and its operating method that can be directly connected to the network without network-related settings.

According to the operation method of the plug-and-play network device of the present invention, the network device is set on the path that the signal leading to the external network must pass through in a local area network, and the local area network has a pair of external routers. The method includes: (A) preset a specific IP address that does not exist in the local area network on the network device, so that the network device sends a destination IP address to the specific IP address when a user end sends a message request packet The packet can be intercepted, and the media access control (MAC: Media Access Control) address of the user end can be recorded; (B) the MAC address of a default router is pre-stored on the network device, so that the network device can request a packet in response to the information When returning an information packet, use the MAC address of the default router as the destination MAC address of the information packet; and (C) make the network device replace the MAC address of the user end before sending the information packet; After the destination MAC address of the information packet is determined, the information packet is sent out. In this way, the network device achieves plug-and-play functionality.

In addition, a computer-readable recording medium of the present invention can be loaded in a plug-and-play network device, and the network device is set in a local area network, and the signal leading to the external network must pass through On the path, the local area network has a pair of external routers, and a specific network protocol address that does not exist in the internal network is preset in the network device and a MAC address of a preset router is pre-stored; and the A program code is recorded in the recording medium, and the program code can execute the following steps in the network device:

(A) When a user end sends out a destination end network protocol for the information request packet of the specific network protocol address, intercepting the information request packet and recording the MAC address of the user end;

(B) when the network device returns an information packet according to the request of the information request packet, using the MAC address of the preset router as the destination MAC address of the information packet; and

(C) Before sending the information packet, the network device replaces the destination MAC address of the information packet with the MAC address of the user end, and then sends the information packet. In this way, the network device achieves the effect of plug and play.

Furthermore, the plug-and-play network device used in the present invention to realize the operation method of the above-mentioned plug-and-play network device is set up on the path that signals must pass through in a local area network, and the local area network has A pair of external routers; the plug-and-play network device is provided with a specific IP address that does not exist in the network and a MAC address of a default router. When a user sends an information request packet whose destination is the specific IP address, intercept the information request packet and record the MAC address of the user end, and when the network device responds to an information packet according to the request of the information request packet , use the MAC address of the default router as the receiving end address of the information packet, and before sending the information packet, replace the MAC address of the default router with the MAC address of the user end, and then send the information packet . In this way, the network device achieves plug-and-play functionality.

Description of drawings

FIG. 1 is an explanatory diagram of related settings when setting up a network device on a local area network in the past;

2 is a network topology diagram of a preferred embodiment of the plug-and-play network device and its operation method of the present invention;

Fig. 3 is the related address table of the network device of this embodiment;

FIG. 4 is a related address table of the user terminal-P in this embodiment;

FIG. 5 is a flow chart of the packet transmission operation among the network device, the client-P and the local area network in this embodiment.

Description of figure number

1, 4........Network Devices 2...........Local Area Network

3, 6.....External routers 20.....must pass the path

Detailed ways

The plug-and-play network device of the present invention and its operation method are described in detail below through the preferred embodiment and accompanying drawings:

As shown in Figure 2, it is a preferred embodiment of the plug-and-play network device and its operation method of the present invention, wherein the local area network 2 (IP: 192.168.1.x) can be inside an enterprise, a building or A small network composed of a plurality of terminal computers (represented by client-P, client-Q, client-R, and client-F) in a limited area, and the local area network 2 is through A pair of external routers 3 are connected to the Internet.

In this embodiment, the plug-and-play network device 1 (hereinafter referred to as the network device 1) is set between the user terminal and the external router 3 in the local area network 2, and the network device 1 is used in this embodiment A web page (web) server, but can also be applied to, for example, a file transfer protocol (FTP: FileTransfer Protocol) server, a mail server, or other network value-added services provided on a network node (node). And the physical structure of the network device 1 is similar to a transparent bridge (bridge) conforming to the 802.11. Signals passing through it can freely enter and exit without affecting the circulation of signals on the path 20 . And the network device 1 does not set an IP address in the local area network 2 without a network manager or user, that is, for all user terminals (ie user computers) in the local area network 2, they do not know the network device 1 However, all client terminals will pass through the network device 1 when they want to connect to the external router 3 .

Based on the above problem, through the present invention, the network device 1 will allow all clients in the local area network 2 to connect and log in without any network-related settings. Therefore, the operation method of the network device 1 of this embodiment is as follows:

First, as shown in Figure 3 and in conjunction with Figure 5, in step (a), the network device 1 is provided with two Ethernet ports eth0 and eth1, one in and one out, wherein eth0 is preset with a MAC address (such as ff.aa.aa .aa.aa.aa) and a specific IP address (such as 168.1.1.1) and the IP of the default router (or virtual router, because it does not actually exist) corresponding to the specific IP (such as 168.1.1.254), and The specific IP address is preferably an IP that is bought out from the IP applicant and does not exist in other networks. eth1 is preset with a MAC address (eg ff.bb.bb.bb.bb.bb). And as shown in Figure 3, be provided with a flash memory (hereinafter referred to as Flash) 11 and an Address Resolution Protocol high-speed cache (Address Resolution Protocol Cache) 12, (hereinafter referred to as ARP cache) in the network device 1, prestored with network device 1 in the Flash 11 The specific IP address (168.1.1.1), the IP address (168.1.1.254) and its MAC address (aa.aa.aa.aa.aa.aa) of the default router, when the network device 1 is turned on (step b) At this time, the above-mentioned specific IP (168.1.1.1) stored in Flash 11 is taken out as the IP of eth0 of network device 1, and its corresponding preset router is set to 168.1.1.254, while another preset IP (168.1.1.1) stored in Flash 11 It is assumed that the IP and MAC addresses of the router are automatically loaded in the ARP Cache 12.

Therefore, as shown in step (c) of FIG. 5 and in conjunction with FIG. 2 and FIG. ee.ff) When wanting to connect to the web server of the network device 1, and input the specific IP address (168.1.1.1) on the browser (browser) of its computer, the client-P computer will find the specific IP address (168.1 .1.1) does not belong to the local area network 2, so it is desired to send the specific IP address (168.1.1.1) to the external router 3 of the local area network by means of a packet. However, before the IP packet is encapsulated into an Ethernet packet under the layer 2 (data link layer) of the Open System Interconnection (OSI: Open System Interconnection), the MAC address of the destination (that is, the external router 3) must be obtained through the ARP protocol.

Therefore, as shown in step (d) of FIG. 5 , the client-P broadcasts an ARP request packet externally to inquire about the MAC address whose IP is 192.168.1.254 (that is, its external router 3 ). Therefore, when the external router 3 receives the broadcast ARP packet, it will return an ARP response packet with its MAC address (such as aa.bb.11.22.33.44) to the user end as shown in step (e) of Figure 5- p. Moreover, since the network device 1 conforms to the standard bridge (bridge) protocol, it does not affect the exchange of ARP packets.

Next, after the user obtains the MAC address of the external router 3, as shown in step (f) of Figure 5, the user-P prepares to send an http request packet to the external router 3, and the destination IP address of the packet sent at this time is 168.1.1.1, MAC address is external router 3 MAC address (aa.bb.11.22.33.44) and port (port) Transmission Control Protocol port (TCP port: Transfer Control Protocol Port) number is 80.

And because the network device 1 is located between the local area network 2 and the external router 3, so, as shown in step (g) of Figure 5, all packets passing through the network device 1 will be seen by the network device 1 and check its destination IP. Therefore, when the specific IP address packet is sent to the eth0 network port of the network device 1, when the bottom layer of the network device 1 (which is a driver program) finds that the destination IP and port number of the packet are 168.1.1.1 and 80 (ie eth0 own IP: 168.1.1.1), it receives the specific IP address packet, and replaces the MAC address of the destination end of the packet (aa.bb.11.22.33.44) with its own MAC address (ff.aa.aa.aa.aa .aa) (the purpose of this approach is not to affect the compliance of the device itself with the network communication specification), and then upload to a server included therein (not shown in the figure) to further process the requirements of the user end-P.

At the same time, as shown in step (h), the bottom layer of the network device 1 will record the connection according to the connection (the definition of connection refers to the connection established according to the source IP, destination IP, source port number and destination port number). The source MAC address (aa.bb.cc.dd.ee.ff) of a specific IP packet.

As can be seen from the above description, the present invention allows the user terminal-P to operate normally by presetting a specific IP address on the network device 1 and using the ARP request mechanism without the user needing to make any settings on the network device 1. After the network transmission protocol sends the packet with the specific IP address, the network device 1 can receive the packet with the specific IP address by determining the destination IP address of the packet.

Continuing with the above step (h), as in step (i), when the web server of the network device 1 intends to respond to an information packet (such as a web page) to the client-P for the request (http request) of the client-P, As shown in step (j), the network device 1 will find out that the IP (192.168.1.1) of the destination end of the information packet (that is, the user-P computer) and the IP (eth0) of the network device 1 itself do not belong to the same network. domain, so the information packet needs to be sent to its default router, but before that, as mentioned above, the MAC address of its default router must be obtained first. Therefore, the network device 1 will broadcast the ARP request packet, but before that, according to the network protocol specification, the network device 1 will first check whether the MAC address of the default router is pre-stored in its ARP Cache 12, and if so, directly use it.

Therefore, in the aforementioned step (a), the IP address (168.1.1.254) and the MAC address (aa.aa.aa.aa.aa.aa) of the default router are stored in the ARP Cache 12 by software programs or other methods . Therefore, as shown in step (k) of Figure 5, the network device 1 will obtain the MAC address of the preset router from the ARP Cache 12 as the destination MAC address of the information packet, and then send the information packet to its bottom layer ( i.e. its network driver).

Based on the above, the bottom layer of the network device 1 will check all the packets entering and leaving the network device 1 before sending them out. Therefore, in order to enable the network device 1 to smoothly deliver the information packets to the user end under the condition of following the network transmission protocol- P, as shown in step (1) of Figure 5, when the information packet is sent to the bottom layer, when the bottom layer checks that the source end IP and port number of the information packet are 168.1.1.1 and 80 (i.e. its own IP and port number ), that is, query the user-side MAC address (aa.bb.cc.dd.ee.ff) previously recorded according to the connetcion value to replace the destination MAC address of the information packet (aa.aa.aa.aa.aa .aa), and then send the information packet (step m).

In this way, the information packet will finally be transmitted to the user end-P according to the MAC address of the user end-P (although it seems that the network device 1 sends the information packet to its virtual default router), thereby , so that the network device 1 can respond to the request of the user terminal-P in the local area network 2 without setting up the relevant settings of the network, so that the network device 1 looks as if it is set up in the local area network 2 and can The network server directly communicates with the client-P two-way, so as to achieve the purpose and effect of plug and play.

As can be seen from the above description, the present invention, without changing the original network transmission protocol (that is, following all relevant protocols of packet transmission in the network environment), uses the operation of the above-mentioned network device 1 to make the network set up in the local area network 2 The device 1 can be used by all users in the local area network 2 to connect and perform two-way communication without any settings. For users who are generally not familiar with network construction technology, it provides a high degree of convenience. For the network administrators within the enterprise, it is also possible to significantly reduce their workload because they are exempted from setting IP addresses for each network node device one by one.

After describing the preferred embodiments of the present invention in detail, those skilled in the art can clearly understand that the above content is only used to illustrate the present invention, but not to limit the scope of the present invention.

Claims (9)

1. the How It Works of the network equipment of a plug and play, described network equipment be located at lead to external network in the LAN signal must through the path on, and described LAN has a pair of outer router; It is characterized in that:

Described method comprises:

(A) a default specific network protocols address that is not present in the described LAN on described network equipment, make described network equipment when user end sends the destination procotol and is the information requirements package of described specific network protocols address, but the described package of intercept and write down the media access control address of described user's end;

(B) on described network equipment, the prestore media access control address of a default router, when making described network equipment return a message packet, use the destination media access control address of the media access control address of described default router as described message packet in response to this information requirements package; And

(C) make described network equipment before sending described message packet, replace the destination media access control address of described message packet with the media access control address of described user end after, more described message packet is sent.

2. the How It Works of the network equipment of a kind of plug and play according to claim 1, it is characterized in that: when the specific network protocols address of step (A) makes the user in the described LAN hold desire to link described network equipment, need to carry out the ARP information exchange with described external router earlier and after obtaining the media access control address of described external router, with the destination media access control address of described media access control address as described information requirements package.

3. according to the How It Works of the network equipment of the described a kind of plug and play of claim 1, it is characterized in that: described network equipment more comprises a flash memory and an address analytic protocol cache, and the media access control address of the described default router in the step (B) and one internet protocol address are to leave in the described flash memory, when described network equipment activates, promptly from described flash memory, take out the media access control address and the internet protocol address of described default router automatically and deposit in the described address analytic protocol cache.

4. the recording medium of an embodied on computer readable, it can be by mounting in the network equipment of a plug and play, described network equipment be located in the LAN lead to external network signal must through the path on, described LAN has a pair of outer router, and is preset with one in the described network equipment and is not present in the specific network protocols address in this internal network and prestores the media access control address of a default router; And record a program code in the described recording medium, described program code can be carried out the following step in described network equipment:

(A) when user end sent the destination procotol and is the information requirements package of described specific network protocols address, the described information requirements package of intercept also write down the media access control address of described user's end;

(B) when described network equipment returns a message packet according to the requirement of described information requirements package, use the destination media access control address of the media access control address of described default router as described message packet; And

(C) make described network equipment before sending described message packet, replace the destination media access control address of described message packet with the media access control address of described user end after, more described message packet is sent.

5. the recording medium of a kind of embodied on computer readable according to claim 4, it is characterized in that: in step (A), when described specific network protocols address will make the user in the described LAN hold desire to link described network equipment, need to carry out the ARP information exchange with described external router earlier and after obtaining the media access control address of described external router, with the destination media access control address of described media access control address as described information requirements package.

6. the recording medium of a kind of embodied on computer readable according to claim 4, it is characterized in that: described network equipment more comprises a flash memory and an address analytic protocol cache, and the media access control address of the described default router in the step (C) and one internet protocol address are to leave in the described flash memory, when described network equipment activates, promptly from described flash memory, take out the media access control address and the internet protocol address of described default router automatically and deposit in the described address analytic protocol cache.

7. the network equipment of a plug and play, be erected at lead to external network in the LAN signal must through the path on, and described LAN has a pair of outer router; It is characterized in that:

Described network equipment comprises:

One is not present in the specific network protocols address in the described LAN, make when user end sends the destination procotol and is the information requirements package of described specific network protocols address, but the described information requirements package of described network equipment intercept and write down the media access control address of described user's end; And

The media access control address of one default router, when described network equipment responds a message packet according to the requirement of described information requirements package, use the destination media access control address of the media access control address of described default router as described message packet, and before described message packet is sent, after replacing the media access control address of described default router with the media access control address of described user end, more described message packet is sent.

8. the network equipment of a kind of plug and play according to claim 7, described specific network protocols address it is characterized in that: when will make the user in the described LAN hold desire to link described network equipment, need to carry out the ARP information exchange with described external router earlier and after obtaining the media access control address of described external router, with the destination media access control address of described media access control address as described information requirements package.

9. the network equipment of a kind of plug and play according to claim 7, it is characterized in that: described network equipment more comprises a flash memory and an address analytic protocol cache, and the media access control address of the default router of described network equipment and one internet protocol address leave in respectively in the described flash memory, when described network equipment activates, promptly from described flash memory, take out the media access control address and the internet protocol address of described default router automatically and deposit in the described address analytic protocol cache.

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