CN1384642A - Method of adding subscriber's security confirmation to simple network management protocol - Google Patents
Method of adding subscriber's security confirmation to simple network management protocol Download PDFInfo
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- CN1384642A CN1384642A CN 01117989 CN01117989A CN1384642A CN 1384642 A CN1384642 A CN 1384642A CN 01117989 CN01117989 CN 01117989 CN 01117989 A CN01117989 A CN 01117989A CN 1384642 A CN1384642 A CN 1384642A
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- network management
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Abstract
In order to raising the security of SNMPvl, subscriber's security confirmation is added to simple network management protocol and one transmission control protocol (TCP) connection is established between the network management station and the managed equipment. When the verification is passed, the TCP connection is maintained, and when not, the TCP connection is broken. In case the TCP security connection is broken, the network management station will be deleted from the list. The security confirmation protocol bridges the gap of SNMPvl. During the subscriber's confirmation, the cipher is MD5 ciphered before transmission for ever higher security. The protocol may be applied in both fixed address network management station and dynamic address network management station.
Description
The present invention relates to the method for network management, relate more specifically to increase the method for the fail safe of Simple Network Management Protocol-version one (SNMPv1) by safety verification based on the user.
In IP network, network management workstation is with the general Simple Network Management Protocol (SNMP) that adopts defined in the RFC1157 between the managed device, and snmp protocol has a plurality of versions, comprises version one (SNMPv1), version two (SNMPv2) and version three (SNMPv3).SNMPv1 adopts the verification mode based on group's name, carries a community name string exactly in the header of each request message that network management workstation sends, and group's name is divided into two ranks: read-only group name and read-write community name.In GET, GETNEXT request message, must carry read-only group name or read-write community name; In the SET request message, must carry the read-write community name.After OAMAgent on the equipment was received request message, whether consistent with the appropriate level group name of preserving in the equipment according to community name string, whether decision accepted this message.
In the SNMPv1 agreement, because group's name is as a character string in the SNMP message, in IP network,, be easy to be intercepted and captured by other people with expressly transmitting, the fail safe of equipment can not get good guarantee.
On the equipment in existing data network, the SNMPv1 agreement adopts in a large number.In order to strengthen fail safe, generally used following method: configuration access main control system tabulation on equipment, preservation can be visited the network management workstation address of this equipment.Network management workstation in the table within the rule can not be visited this equipment.A shortcoming of this method is: the access control Host List is applicable to the situation of fixed address network management workstation by manual configuration, and is not suitable for the situation of dynamic address network management workstation.Relevant this prior art on the one hand can be consulted by mountain range Xian Dao and evergreen " NMP and the application and development " book write of peace, and this book is published in July, 1998 by publishing house of Tsing-Hua University.
Purpose of the present invention provides the method that a kind of safety verification based on the user increases the fail safe of Simple Network Management Protocol-version one (SNMPv1), so that solve the not enough problem of fail safe of SNMPv1.
Another object of the present invention is to make this method can guarantee that fixed address network management workstation and dynamic address network management workstation can both visit managed device safely.
Above-mentioned purpose of the present invention is achieved through the following technical solutions: a kind of method that increases the user security checking on Simple Network Management Protocol, the transmission of Simple Network Management Protocol (SNMP) message is based on connectionless User Datagram Protoco (UDP) (udp protocol), in order to increase the fail safe of SNMPv1, when network management workstation is communicated by letter with managed device, on Simple Network Management Protocol, increase the method for user security checking, comprise the steps:
Network management workstation with main frame to the safe connectivity port of managed device send transmission control protocol (TCP) connection request and with managed device between set up a transmission control protocol (TCP) and be connected;
Between network management workstation with main frame and managed device, carry out the checking of a user name and password;
If the verification passes, will keep this TCP to be connected between network management workstation and the managed device, connection at this moment claims safe connection, and managed device can periodically be verified to network management workstation later on;
Network management workstation is by after verifying, managed device adds this network management workstation address and corresponding grade in the tabulation of access control host address to, and managed device is verified the SNMP request message of receiving with the access control Host List;
Managed device is searched access control host address tabulation, legitimacy is carried out in the source of SNMP request message judge, denied access in the time of in the source address of the request message table within the rule, the source address of request message are in this tabulation but operating right denied access when not enough;
If authentication failed, TCP connects and will disconnect, and when safety connected disconnection, this network management workstation address will deletion from this tabulation.
Method of the present invention also comprises following additional technical feature:
The user name of described checking can be divided into different grades, corresponding different operating rights.
Described managed device is preserved an access control host address tabulation, and writing down all in the access control Host List can be by the network management workstation address and the corresponding grade of snmp protocol access means.
The packet of described safety verification agreement is divided into packet header and two parts of data.
There are four bytes described header part, and data division is optionally, by the bag type decided.
Four bytes of described header part are:
" length " is the total length of message, comprises packet header and data;
" version " is version number, is 1 at present;
" type " is type of message, and value is as follows:
1 expression: inquiry packet,
2 expressions: respond packet,
3 expressions: checking is bag as a result;
" coding " is the coding of corresponding certain message.
Described " coding " is the coding of corresponding certain message, and its coded system is:
(1) when " type "=1, promptly when " inquiry packet ", " coding "=1 shows that Authentication-Type is MD5, is " magic numeral " i.e. random number at this moment in " data " territory;
(2) when " type "=2, promptly when " respond packet ", " coding "=1 shows that Authentication-Type is MD5,
In " data " territory be: " user name "+MD5 (" magic numeral "+pass word);
(3) when " type "=3, promptly when " checking result ",
" coding "=1, expression is proved to be successful,
" coding "=2, the expression authentication failed,
When being proved to be successful, first byte representation user gradation in " data " territory.
The safety of described safety verification agreement connects during the maintenance, and one or more SNMP requests can be arranged between network management workstation (1) and the tube apparatus (2).
The introducing of safety verification agreement of the present invention has remedied the defective of SNMPv1 protocol safety aspect.In the authentication procedures, password transmits after by md5 encryption, and fail safe is than higher.For fixed address network management workstation and dynamic address network management workstation, this agreement can be applied, and therefore, this method has improved the fail safe of Simple Network Management Protocol.
Existing accompanying drawings embodiments of the invention are so that further understand method of the present invention.
Fig. 1 is the schematic diagram that safety connects in the method for the present invention;
Fig. 2 is the schematic diagram that the packet of safety verification agreement in the method for the present invention constitutes;
Fig. 3 is the schematic diagram of safety verification protocol theory in the method for the present invention;
Fig. 4 is the schematic diagram of safe establishment of connection, maintenance and disconnection in the method for the present invention.
Fig. 1 is the schematic diagram that safety connects in the method for the present invention, a kind of method that increases the user security checking on Simple Network Management Protocol is shown, the transmission of Simple Network Management Protocol (SNMP) message is based on connectionless User Datagram Protoco (UDP) (udp protocol), in order to increase the fail safe of SNMPv1, when network management workstation 1 is communicated by letter with managed device 2, on Simple Network Management Protocol, increase the method for user security checking, comprise the steps:
Between network management workstation 1 with main frame and managed device 2, carry out the checking of a user name and password;
If the verification passes, will keep this TCP to be connected between network management workstation 1 and the managed device 2, connection at this moment claims safe connection, and managed device 2 can periodically be verified to network management workstation 1 later on;
After network management workstation 1 has passed through checking, managed device 2 this network management workstation address and corresponding grade are added in the tabulation of access control host address (step 4), the SNMP request message 5 that managed device 28 pairs of usefulness access control Host Lists are received is verified;
Managed device 2 is searched the tabulation of access control host address, the SNMP request message is carried out legitimacy judge (step 6), denied access in the time of in the source address of the request message table within the rule, the source address of request message are in this tabulation but operating right denied access when not enough;
If authentication failed, TCP connects and will disconnect, and when safety connected disconnection, this network management workstation address will deletion from this tabulation.
Above-mentioned TCP connects and is called safe connection.
The user name of described checking can be divided into different grades, corresponding different operating rights.
Described managed device 2 is preserved the tabulation of access control host address, and writing down all in the access control Host List can be by the network management workstation address and the corresponding grade of snmp protocol access means.Proof procedure when setting up the safety connection is called the safety verification agreement.
Fig. 2 is the schematic diagram that the packet of safety verification agreement in the method for the present invention constitutes; The packet of safety verification agreement is divided into packet header and two parts of data.There are four bytes the header part, and data division is optionally, by wrapping type decided:
" length " is the total length of message, comprises packet header and data;
" version " is version number, is 1 at present;
" type " is type of message, and value is as follows:
1 expression: inquiry packet,
2 expressions: respond packet,
3 expressions: checking is bag as a result;
" coding " is the coding of corresponding certain message:
(1) when " type "=1, promptly when " inquiry packet ", " coding "=1 shows that Authentication-Type is MD5 (MD5 is a kind of algorithm, is used to calculate message digest),
Be " magic numeral " i.e. random number at this moment in " data " territory,
Example:
When " magic numeral "=12345,
Content is a character string in " data " territory: " 12345 ";
(2) when " type "=2, promptly when " respond packet ", " coding "=1 shows that Authentication-Type is MD5,
In " data " territory be: " user name "+MD5 (" magic numeral "+pass word),
Example:
User name: linwei,
Password: 3734lw,
The magic numeral: 12345,
Then summary data is: MD5 (" magic numeral "+pass word)=MD5 (" 123453734lw ")=
2ccf0210c9882bedc19a1b2d065a8baa，
Then content is in " data " territory:
″linwei\02ccf0210c9882bedcl9a1b2d065a8baa\ 0″，
User name and summary data all have ' 0 ' ending;
(3) when " type "=3, promptly when " checking result ",
" coding "=1, expression is proved to be successful,
" coding "=2, the expression authentication failed,
When being proved to be successful, first byte representation user gradation in " data " territory.
Fig. 3 is the schematic diagram of safety verification protocol theory in the method for the present invention, the message interaction process of a proving period of safety verification agreement is shown: as long as (for example: TCP 808 ports) a TCP connection has been set up in initiation to network management workstation 1 to the safety verification port 9 of managed device 2, managed device 2 will regularly send inquiry packet 10 to network management workstation 1 and verify, network management workstation 1 sends respond packet 11 to the safety verification port 9 of managed device 2, up to the checking result be successfully 12 or the checking result be failure 13 or network management workstation 1 disconnection connection.The length of proving period can dispose on managed device 2.
Fig. 4 is the schematic diagram of safe establishment of connection, maintenance and disconnection in the method for the present invention.As shown in Figure 4: the overall process that safety connects foundation, keeps and disconnects in the method for the present invention comprises the steps:
(1) network management workstation 1 is initiated TCP connection request 3 to the safety verification port of managed device 2;
(2) after the TCP connection was set up, managed device 2 carried out the checking first time according to the safety verification agreement to network management workstation 1, if receive that response and checking result are successfully, the safety connection between managed device 2 and the network management workstation 1 is promptly set up and kept;
(3) managed device 2 is regularly verified network management workstation 1 at set intervals, authenticates to the n time checking the second time as shown in Figure 4; Checking is passed through, and then safety connects maintenance;
(4) if certain when checking, if the inquiry packet of managed device 2 sends failure, perhaps inquiry packet sends successfully but does not receive the respond packet of network management workstation 1, and perhaps managed device 2 is received respond packet but the checking result is failure, and managed device 2 just disconnects and being connected safely of this network management workstation 1;
(5) the safety connection is based upon on the TCP connection, has disconnected if TCP connects, and safety connects also automatic disconnection;
(6) during safety connected maintenance, managed device thought that network management workstation is reliable, and the method that at this moment increases the user security checking on Simple Network Management Protocol is effectively, and at this moment one or more SNMP requests can be arranged between network management workstation and tube apparatus.
Describe as can be known according to the foregoing description; though the present invention increases the method for user security checking on Simple Network Management Protocol the fail safe that is applied to solve SNMPv1 has only been described; but those of ordinary skill in the art can be according to the basic step of the inventive method; make amendment or alternative applications in the method for similar data transmission, its flesh and blood also should belong to the protection range of method that book of the present invention limits.
Claims (8)
1, a kind of method that on Simple Network Management Protocol, increases the user security checking, the transmission of Simple Network Management Protocol (SNMP) message is based on connectionless User Datagram Protoco (UDP) (udp protocol), in order to increase the fail safe of SNMPv1, at network management workstation (1) and managed device (2) when communicating by letter, on Simple Network Management Protocol, increase the method for user security checking, it is characterized in that comprising the steps:
Network management workstation (1) with main frame to the safe connectivity port of managed device (2) send transmission control protocol (TCP) connection request (3) and with managed device (2) between set up a transmission control protocol (TCP) and be connected;
Has the checking of carrying out a user name and password between network management workstation of main frame (1) and the managed device (2);
If the verification passes, will keep this TCP to be connected between network management workstation (1) and the managed device (2), connection at this moment claims safe connection, and managed device (2) can periodically be verified to network management workstation (1) later on;
Network management workstation (1) is by after verifying, managed device (2) adds this network management workstation address and corresponding grade in the tabulation of access control host address (4) to, and managed device (2) is verified the SNMP request message of receiving (5) with access control Host List (8);
Managed device (2) is searched access control host address tabulation (8), legitimacy is carried out in the source of SNMP request message judge (6), denied access in the time of in the source address of the request message table within the rule, the source address of request message are in this tabulation but operating right denied access when not enough;
If authentication failed, TCP connects and will disconnect, and when safety connected disconnection, this network management workstation address will deletion from this tabulation.
2, method according to claim 1 is characterized in that: the user name of described checking can be divided into different grades, corresponding different operating rights.
3, method according to claim 2 is characterized in that: described managed device (2) is preserved an access control host address tabulation, and writing down all in the access control Host List can be by the network management workstation address and the corresponding grade of snmp protocol access means.
4, method according to claim 3 is characterized in that: the packet of described safety verification agreement is divided into packet header and two parts of data.
5, method according to claim 4 is characterized in that: there are four bytes described header part, and data division is optionally, by the bag type decided.
6, method according to claim 5 is characterized in that: four bytes of described header part are:
" length " is the total length of message, comprises packet header and data;
" version " is version number, is 1 at present;
" type " is type of message, and value is as follows:
1 expression: inquiry packet,
2 expressions: respond packet,
3 expressions: checking is bag as a result;
" coding " is the coding of corresponding certain message.
7, method according to claim 6 is characterized in that: described " coding " is the coding of corresponding certain message, and its coded system is:
(1) when " type "=1, promptly when " inquiry packet ", " coding "=1 shows that Authentication-Type is MD5, is " magic numeral " i.e. random number at this moment in " data " territory;
(2) when " type "=2, promptly when " respond packet ", " coding "=1 shows that Authentication-Type is MD5,
In " data " territory be: " user name "+MD5 (" magic numeral "+pass word);
(3) when " type "=3, promptly when " checking result ",
" coding "=1, expression is proved to be successful
" coding "=2, the expression authentication failed
When being proved to be successful, first byte representation user gradation in " data " territory.
8, method according to claim 7 is characterized in that: the safety connection of described safety verification agreement also comprises the steps:
During safety connects maintenance, one or more SNMP requests can be arranged between network management workstation (1) and the tube apparatus (2).
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011179899A CN1149787C (en) | 2001-04-29 | 2001-04-29 | Method of adding subscriber's security confirmation to simple network management protocol |
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| CNB011179899A CN1149787C (en) | 2001-04-29 | 2001-04-29 | Method of adding subscriber's security confirmation to simple network management protocol |
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| CN1384642A true CN1384642A (en) | 2002-12-11 |
| CN1149787C CN1149787C (en) | 2004-05-12 |
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| CNB011179899A Expired - Fee Related CN1149787C (en) | 2001-04-29 | 2001-04-29 | Method of adding subscriber's security confirmation to simple network management protocol |
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| CN100366026C (en) * | 2003-07-06 | 2008-01-30 | 华为技术有限公司 | A method for implementing message forwarding control in routing equipment |
| CN100426753C (en) * | 2006-07-24 | 2008-10-15 | Ut斯达康通讯有限公司 | Network managing method based on SNMP |
| CN100444569C (en) * | 2004-03-10 | 2008-12-17 | 松下电器产业株式会社 | Access control system, access control device used for the same, and resource providing device |
| CN100456689C (en) * | 2003-08-06 | 2009-01-28 | 华为技术有限公司 | Network management safety authentication method |
| CN100478936C (en) * | 2004-07-09 | 2009-04-15 | 株式会社知识潮 | Unauthorized connection detection system and unauthorized connection detection method |
| CN100504908C (en) * | 2006-12-26 | 2009-06-24 | 中国电信股份有限公司 | Method and system for protecting radio frequency identification tag and reader data safety |
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| CN101277215B (en) * | 2007-03-28 | 2011-06-08 | 中国电信股份有限公司 | System and method for implementing remote equipment monitoring management by port proxy relay |
| CN102148704A (en) * | 2011-01-19 | 2011-08-10 | 武汉迈威光电技术有限公司 | Software implementation method for universal network management interface of safe switch |
| CN107257302A (en) * | 2017-08-18 | 2017-10-17 | 郑州云海信息技术有限公司 | It is a kind of to strengthen the method and system of snmp protocol safety |
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| CN1748387B (en) * | 2003-02-06 | 2010-12-08 | 松下电器产业株式会社 | Information transmission system and method, electric device or information communication device, electric device or communication control method |
| CN100366026C (en) * | 2003-07-06 | 2008-01-30 | 华为技术有限公司 | A method for implementing message forwarding control in routing equipment |
| CN100456689C (en) * | 2003-08-06 | 2009-01-28 | 华为技术有限公司 | Network management safety authentication method |
| CN100444569C (en) * | 2004-03-10 | 2008-12-17 | 松下电器产业株式会社 | Access control system, access control device used for the same, and resource providing device |
| CN100478936C (en) * | 2004-07-09 | 2009-04-15 | 株式会社知识潮 | Unauthorized connection detection system and unauthorized connection detection method |
| CN100426753C (en) * | 2006-07-24 | 2008-10-15 | Ut斯达康通讯有限公司 | Network managing method based on SNMP |
| CN100504908C (en) * | 2006-12-26 | 2009-06-24 | 中国电信股份有限公司 | Method and system for protecting radio frequency identification tag and reader data safety |
| CN101277215B (en) * | 2007-03-28 | 2011-06-08 | 中国电信股份有限公司 | System and method for implementing remote equipment monitoring management by port proxy relay |
| CN101282234B (en) * | 2007-04-06 | 2010-12-29 | 中兴通讯股份有限公司 | Method for packet setting proxy multivariate based on simple network management protocol |
| CN102148704A (en) * | 2011-01-19 | 2011-08-10 | 武汉迈威光电技术有限公司 | Software implementation method for universal network management interface of safe switch |
| CN107770116A (en) * | 2016-08-15 | 2018-03-06 | 深圳华云数码有限公司 | The safe verification method and the network equipment of dialogue-based connection |
| CN107257302A (en) * | 2017-08-18 | 2017-10-17 | 郑州云海信息技术有限公司 | It is a kind of to strengthen the method and system of snmp protocol safety |
| CN111866298A (en) * | 2019-04-26 | 2020-10-30 | 佳能株式会社 | Information processing apparatus, storage medium, and control method |
| US11354073B2 (en) | 2019-04-26 | 2022-06-07 | Canon Kabushiki Kaisha | Information processing apparatus, storage medium, and control method |
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