CN1136707C - Adaption method for integrating internet with sychronous optical network - Google Patents

Abstract

The present invention relates to an adapting method for integrating the internet with a synchronous optical network. The present invention improves the defects of no support to the application of low-order virtual containers, over-high cost of partial treatment of hardware retransmission, over-high expense for optical packet switching, unclear definition of the value of a retransmitting timer, low efficiency due to a filling function, etc. in the prior art. Moreover, the present invention proposes that integration and adaptation between an internet protocol and the synchronous optical network be solved by using one factor of SONET link access procedure to replace two factors comprising a point-to-point protocol and a high-grade data chain procedure; the conception simultaneously supports the fourth version and the sixth version of the internet protocol.

Description

A kind of adaptation method that is used for internet and Synchronous Optical Network fusion

Technical field

The data that the present invention relates to internet transmit the field, it is a kind of adaptation method that is used for internet and Synchronous Optical Network (english abbreviation SONET) fusion, be mainly used in the core switch router, the edge switch router, based on the high low-end switch of packet switch, user side integrated access equipment and interconnecting and interworking equipment relevant etc. with internet.

Background technology

According to the interrelated data introduction, now be used for the adaptation method that internet and Synchronous Optical Network merge, be to adopt " point-to-point protocol " (english abbreviation PPP) to add " high-level data link rules " (english abbreviation HDLC).At internet engineering duty group (english abbreviation IETF), it is defined as (code name) RFC1619 (RFC is the request comment, English Request For Comments).As everyone knows, popularization and application along with computer, the network transmission technology supporting with computer constantly develops, with the internet be the computer network of representative by Synchronous Optical Network constantly to extending all over the world, allow electronic information propagate, make electronic information reach each corner in the world by wireless and microwave transmission mode simultaneously with the fastest speed.Along with the day by day increase of electronic information by transmission volume, the quality of electronic information transmission becomes the problem that people pay close attention to day by day.Internet has the unified IP delivery platform in the world, can move countless application and business thereon.Synchronous Optical Network (english abbreviation SONET) is that at present best in the world and existing telecommunications transmits one of net resource, and both have extremely strong complementarity, are containing several hundred billion dollars market prospects.Internet protocol (english abbreviation IP) is directly at SONET optical cable online operation, is countries in the world in recent years, each big telecommunications manufacturer, and the focus of operator and each computation machine company market contention also is the key point that telecommunications network and computer network merge.Safety, fast, high-quality is by internet and other Network Transmission electronic information, need to adopt corresponding transmission means and adaptation method, not smooth to prevent Network Transmission, information dropout, according to the interrelated data introduction, now be used for the adaptation method that internet and Synchronous Optical Network merge, present " point-to-point protocol " (english abbreviation PPP) that adopts, it can encapsulate 30 multiple network agreements, contain and be useful on internet " internet protocol the 4th edition (English IPV4); this protocol fitting method is successful by the MODEM online; also have fire compartment wall, but if be used for Synchronous Optical Network (english abbreviation SONET), just comes with some shortcomings and defective.Mainly show:

(1) for the application of Lower Order Virtual Container (english abbreviation LOVC), do not have the standard support, cause IP over SONET can not be used for the internet edge and insert;

(2) for per second 2.5G gigabit and above speed thereof, hardware forwarding part expense is too big during development equipment, being used for " internet protocol (english abbreviation IP) is directly at wavelength division multiplexing optical cable net (english abbreviation IP over WDM) " goes up when moving, all the more so, because the RFC1619 regulation: recommend to use " LCP (english abbreviation LCP) " and magic number (English is expressed as Magic Number).These two more complicated;

When (3) adopting RFC1619, because PPP need connect, the default value of retransmission timer is decided to be 3 seconds in PPP.For high-speed link, this method is too blunt.Use for concrete engineering, should require to support speed range all (differing from 4032 times approximately) from per second 2 megabits to per second 10000 megabits.So the value of retransmission timer should be determined according to the time delay that circuit comes and goes.These are not all made stipulations in RFC1619, thereby uncertainty can occur when the apparatus interconnection of different manufacturers;

(4) fill function (English is expressed as Padding Function), the information field of PPP generally will be filled into maximum receive unit (english abbreviation MRU, general provision is 1500 bytes on internet).For general internet packet, as the application of browser (English is expressed as WWW) online (this kind application account for 75% that whole internet uses), the average data packet length is 330 bytes, has average about 350% to be to flog a dead horse like this, and efficient is very low.In addition, it is information field that this filling field also needs a function which is distinguished at receiving terminal, and which is to fill field.This has increased processing expenditure again;

(5) the whole rules of LCP (english abbreviation LCP) comprise 10 kinds of configuration data bags (English is expressed as configurationpacket), 16 kinds of state events (English is expressed as Event) and 12 kinds of actions (English is expressed as Action), and the packet switch (light---light) that these complicated mechanism is used for light is to be difficult to realize.Even worked it out, cost is high too.

Summary of the invention

The objective of the invention is, improved, and propose and design a kind of adaptation method that is used for internet and Synchronous Optical Network fusion that is applicable to various situations at deficiency and defective that prior art exists; Conception of the present invention is the sonet link access regulation (english abbreviation LAPS) that only keeps byte-oriented between internet protocol (english abbreviation IP) and Synchronous Optical Network (english abbreviation SONET), replace address field with many service access points, the encapsulation of realization multi-protocols, can support whole speed ranges of from the Lower Order Virtual Container to the higher order virtual container, (comprising cascade), also be particularly suitable for using the packet switch interface of light, uncertainty without any agreement, this conception can not only solve new equipment development and problems of operation, and has found an extraordinary outlet for the existing telecommunication transmission resource that exceeds 100 billion of China.A kind of adaptation method that is used for internet and Synchronous Optical Network fusion, adopt the following step:

Receive packet from the network layer device of internet, the type of recognition data bag produces the SAPI identifier according to the type of discerning, and described packet is converted to the professional code-point of segmentation of first kind frame and transmission priority; Described first kind frame is packaged into the frame format that comprises beginning flag, address field, control field, information field, Frame Check Sequence field and termination flag, to form the second class frame; By the transmission priority of the professional code-point defined of segmentation, the second class frame is mapped in the mode towards eight hytes on the virtual container of single Synchronous Optical Network or the cascade channel formed by the virtual container of a plurality of Synchronous Optical Networks on.

Aforesaid adaptation method, the SAPI identifier of the described second class frame is corresponding to address field or be inserted on two the information field bytes of the most close control field.

Aforesaid adaptation method, described cascade channel is by the virtual container (A1 of two or more same rates with the Synchronous Optical Network in path, A2, An) form, the bit-order of mapping is: the 1st bit of virtual container A1, the 1st bit of virtual container A2, the 1st bit of virtual container A3 ... the 1st bit of virtual container An, the 2nd bit of virtual container A1, the 2nd bit of virtual container A2, the 2nd bit of virtual container A3 ... the 2nd bit of virtual container An, the N bit of virtual container A1, the N bit of virtual container A2, the N bit of virtual container A3 ... the N bit of virtual container An, the maximum number bits of each virtual container are the values of ANSI T1.105 defined.

Aforesaid adaptation method, the virtual container of described Synchronous Optical Network and the bandwidth after the cascade thereof, payload parameter are;

Virtual container--4 its bandwidth 150336 kilobits/second payloads 149760 kilobits/second

Its bandwidth 601304 kilobits/second payloads 599040 kilobits/second of virtual container--4-4c

Its bandwidth 2405376 kilobits/second payloads 2396160 kilobits/second of virtual container--4-16c

Its bandwidth 9621504 kilobits/second payloads 9584640 kilobits/second of virtual container--4-64c

Its bandwidth 38486016 kilobits/second of virtual container--4-192c

Aforesaid adaptation method, what the method for described transmission and reception was used is not confirm formula information transfer service pattern (UITS), has only a key element LAPS at the 2nd layer, does not have flow control, does not also carry out any affirmation formula operation.

Aforesaid adaptation method, the method of described transmission and reception, after FCS calculating is finished, transmit leg is checked the entire frame content between two flag of frame, whenever run into " 0 * 7e " time it is replaced with " 0 * 7d; 0 * 5e ", whenever run into " 0 * 7d " and the time it is replaced with " 0 * 7d, 0 * 5d "; The recipient, before FCS calculates, as long as run into " 0 * 7d, 0 * 5e " or " 0 * 7d, 0 * 5d " then do opposite conversion.

Aforesaid adaptation method, described data link layer LAPS provides the primitive of service and parameter to be respectively to the 3rd layer:

DL-UNACK-DATA asks (user data, version field, DS code-point or IPv4 business type field)

" data link-do not confirm-data " primitive is represented in DL-UNACK-DATA indication (user data) wherein DL-UNACK-DATA, and it has request (Request) and indication (Indication) two classes; User data, version field and DS code-point or IPv4 business type field correspond respectively to three kinds of parameters, promptly whole " protocol Data Unit " in the layer 3 IP bag (PDU), " version field " (Version) and " segmentation professional (Differentiated Services) code-point or IPv4 business type field (TOS) ", when sending as 2 layers of the parameter maps to the of primitive; At the 2nd layer, user data or the information field of the PDU that shines upon as LAPS; " version field " of shining upon service access point identifier (SAPI) as LAPS; " professional (DS) code-point of segmentation " of shining upon or " IPv4 business type field " as a kind of foundation, controlled the formation algorithm; Wherein, the user data maximum is 1,600 eight hytes, keeps its original order and value constant when the LAPS framing; Version field is 4 bits in Ipv4 and Ipv6, be mapped to low four bits of SAPI, keeps its original order and value constant; The DS code-point is type of traffic (Traffic Class) in Ipv6, and the English of IPv4 business type field is " Type of Service " field, the length of DS code-point and IPv4 business type field all is one eight hyte.

Advantage of the present invention with respect to existing RFC1619, has following innovation:

(1) at present more external manufacturers (are RFC1619 according to the PPP over SONET/SDH that internet engineering duty group (english abbreviation IETF) proposes, SONET is meant the Synchronous Optical Network of North America) exploitation, with regard to RFC1619 itself, link layer has PPP (point-to-point protocol) and two kinds of agreements of HDLC (high-level data link rules), more complicated, hardware spending was too big when it was used for the above speed of per second 2.5 gigabits, the present invention only adopts a LAPS key element by contrast, its complexity and HDLC are suitable, saved " LCP (english abbreviation LCP) " and magic number (English the is expressed as Magic Number) mechanism of the complexity among the PPP, the expense of used protocol adaptation reduces greatly;

(2) RFC1619 does not still support the Lower Order Virtual Container of SONET at present, there is not the standard support when application of PPP over SONET/SDH is to the Internet marginal layer or near the comprehensive access of user Side like this, the present invention can support fully to Lower Order Virtual Container by contrast, and is both simple, complete again;

When (3) adopting RFC1619, because PPP need connect, the default value of retransmission timer is decided to be 3 seconds in PPP. for high-speed link, too blunt, use for concrete engineering, should require all to support to the speed range of per second 10000 megabits from per second 1.6 megabits, so the value of retransmission timer should be determined according to the time delay that circuit comes and goes, these are not all made stipulations in RFC1619, thereby when the apparatus interconnection of different manufacturers uncertainty may appear, the present invention adopts and does not confirm formula information transfer service mode by contrast, do not need to connect, also do not need to use retransmission timer, the uncertainty of communicating by letter between any peer-entities can not occur, the application of the speed range from per second 2 megabits to per second 10 gigabits is all supported;

(4) about filling the use of function, the information field of PPP generally will be filled into maximum receive unit (english abbreviation MRU, general provision is 1500 bytes on internet), for general internet packet, as the application of browser (English is expressed as WWW) online (this kind application account for 75% that whole internet uses), packet length is average out to 330 bytes, and average like this having an appointment 350% is to flog a dead horse, and efficient is very low; In addition, it is information field that this filling field also needs a function which is distinguished at receiving terminal, and which is to fill field, and this has increased processing expenditure again, and the present invention is irrelevant with the filling function by contrast, for any internet application, does not have this idle work;

(5) the whole rules of LCP comprise 10 kinds of configuration data bags (English is expressed as configuration packet), 16 kinds of state events (English is expressed as Event), 12 kinds of actions (English is expressed as Action), the packet switch (light---light) that these complicated mechanism is used for light is to be difficult to realize.Even worked it out, cost is high too.By contrast, the present invention does not have these configuration data bags, and state event and action can be used for the packet switch (light---light) of light at an easy rate;

(6) the present invention has considered Ipv4 that is using at present and the Ipv6 that is about to use, supports to have good real world applications characteristics and extensibility in the future with unified LAPS mechanism;

Generally, the present invention is with very letter refining, mode with cheapness solves the protocol adaptation of internet to the SONET telecommunication transmission efficiently, " point-to-point protocol (english abbreviation PPP) and two key elements of high-level data chain rules (english abbreviation HDLC) are supported internet protocol the 4th edition (english abbreviation Ipv4) and the application of internet protocol sixth version (english abbreviation Ipv6) on SONET with key element replacement of sonet link access regulation.

Description of drawings

Fig. 1, conception schematic diagram proposed by the invention

Fig. 2, the present invention are used for the protocol stack structure schematic diagram that Synchronous Transfer Mode transmits the internet packet

Fig. 3, the protocol stack arrangement example schematic of networking of the present invention

Fig. 4, the UNE of internet protocol proposed by the invention and Synchronous Optical Network SONET are for example

Fig. 5, network layer proposed by the invention, the primitive graph of a relation between link layer and the physical layer

Fig. 6, the present invention uses conception figure in national IP over SDH core layer networking

Fig. 7, the present invention is in IP over SDH core layer networking application conception inside the province

Embodiment

Below, embodiments of the invention are described with reference to the accompanying drawings.

Proposed by the invention do not want to be mainly used in the core switch router, the edge switch router, high low-end switch based on packet switch, user side integrated access equipment and interconnecting and interworking equipment relevant etc. with internet, wherein SDH mainly uses in China and Europe, and SONET mainly in the North America, Japan and Hong Kong application.Application framework of the present invention is seen Fig. 1, it is conception schematic diagram proposed by the invention, wherein IPv6 represents the internet protocol sixth version, IPv4 represents internet protocol the 4th edition, SAPI represents the service access point identifier, and network layer adopts internet protocol (IP) (comprising IPv4 and IPv6), and link layer adopts sonet link access regulation (english abbreviation LAPS), physical layer adopts Synchronous Optical Network (SONET), mainly comprises all kinds of high-orders and Lower Order Virtual Container.In this framework, the 3rd layer of service access point that provides of the 2nd course has two, respectively for using based on the packet of IPV4 with based on the packet of IPV6.Their service access point identifier (SAPI) is respectively a decimal number " 4 " and " 6 ".Whole protocol Data Unit in the layer 3 IP bag (english abbreviation PDU), " version field " (English Version), professional (the English Differentiated Services) code-point of segmentation or IPv4 business type field (english abbreviation TOS), when sending as 2 layers of the parameter maps to the of primitive.At the 2nd layer, the information field of the PDU that shines upon as LAPS; The version field of shining upon as service access point identifier (english abbreviation SAPI), and is transferred to the address field of LAPS; The professional code-point of the segmentation of shining upon or IPv4 business type field as a kind of foundation, control formation algorithm.Do not confirm formula information transfer service (UITS) the 2nd layer of employing, it and the 1st layer are also mutual with primitive and parameter by corresponding service access point.Fig. 2 is that the present invention is used for the protocol stack structure schematic diagram that Synchronous Optical Network transmits the internet packet, wherein below LAPS, two kinds of methods of putting into virtual container are arranged, a kind of is that the LAPS frame is put into Lower Order Virtual Container, the mode that Lower Order Virtual Container is interleave with byte is advanced higher order virtual container by the multiplexing structure of SONET is multiplexing, according to multiplex section, the order of regenerator section and photoelectricity transmission section transmits, and then extracts the LAPS frame by opposite order at receiving terminal again; Another kind is the LAPS frame directly to be reflected establish into the synchronous payload of higher order virtual container and seal (english abbreviation SPE), and again according to multiplex section, the order of regenerator section and photoelectricity transmission section transmits, and then extracts the LAPS frame by opposite order at receiving terminal.The protocol stack arrangement example schematic of Fig. 3 networking of the present invention, it is expressed local area network (LAN) and inserts the inlet side of IP over SONET net and the protocol stack arrangement that goes out to hold each node of gateway, LLC presentation logic controlling links sublayer wherein, MAC represents MAC sublayer, SONET represents Synchronous Optical Network, LAN represents local area network (LAN), IPv4 represents internet protocol the 4th edition, IPv6 represents the internet protocol sixth version, TCP represents transmission control protocol, UDP represents User Datagram Protoco (UDP), IP represents internet protocol (general address), and the fusion of " IP over SONET " expression internet protocol and Synchronous Optical Network is at the gateway place, be furnished with SONET and MAC two class physical interfaces simultaneously, and that network layer remains Ipv4/Ipv6 is constant.Fig. 4 be internet protocol proposed by the invention and Synchronous Optical Network SONET UNE for example, wherein, solid line represents to adopt between the node Synchronous Optical Network physical connection, dotted line represents to intend between the node packet exchange of employing, black node is represented the network boundary node, play the gateway effect, Bai Jiedian represents network backbone node, it can overlook IP over sonet network from the angle of node, here it must be emphasized that, in IP over SONET net, only need be on same link the identical (upper-layer protocol certainly of two physical interface speed of equity with physical index, also mutually equal as LAPS with IP), so the IP over SONET physical interface of various different rates can be arranged on each link in the net.What Fig. 5 described is network layer proposed by the invention, primitive graph of a relation between link layer and the physical layer, wherein LAPS provides two service access points, its identifier value (SAPI) equals decimal number " 4 " use for Ipv4, its identifier value (SAPI) equals decimal number " 6 " for Ipv6 usefulness, send out packet to link layer from network layer, use " DL-UNACK-DATA request " primitive, receive packet to network layer from link layer, use " DL-UNACK-DATA indication " primitive; Between link layer and I physical layer, from the link layer to the physical layer, use " PH-DATA request " primitive link setup, use " PH-DATA indication " primitive then to represent to send out the link setup indication to link layer by physical layer.Send out packet to physical layer from link layer, use " PH-DATA request " primitive, receive packet to link layer, use " PH-DATA indication " primitive from physical layer.Fig. 6 is that the present invention uses conception figure in national IP over SDH/SONET core layer networking, wherein black circle is represented the core route exchange device based on IP over sonet equipment, small rectangular block is represented SONET existing on the present national backbone network or WDM transmission equipment, this example is that existing resource is given an example the existing transmission network management of the computer representation at white interface with present Chinese 8 * 8SDH or wavelength division multiplexing (english abbreviation WDM) trunk transit network; After each node city employing has the core switch router of IP overSDH/SONET interface, can form a packet switch core net that extends in all direction, the computer representation at black interface is about to the webmaster of the core switch router net of layout.Fig. 7 is that the present invention is in IP over SONET core layer networking application conception inside the province, wherein black circle is represented the core route exchange device based on IP over sonet equipment, the Xiao Bai circle is represented the branch line route exchange device based on IP overSONET equipment, REG is a regenerative repeater, ADM is an add-drop multiplexer, and LAN is a local area network (LAN); The each province is mostly with the networking of sonet ring type at present, and this example is that existing resource is given an example with present Chinese each province SDH looped network or wavelength-division multiplex system (english abbreviation WDM) trunk transit network; Each districts and cities node city inside the province adopt have the core switch router of IP over SDH/SONET interface after, can form a packet switch core net that is extending in all direction inside the province.

Claims (6)

1. an adaptation method that is used for internet and Synchronous Optical Network fusion comprises the following steps:

Receive packet from the network layer device of internet, the type of recognition data bag produces the service access point identifier according to the type of discerning, and described packet is converted to the professional code-point of segmentation of first kind frame and transmission priority; Described first kind frame is packaged into the frame format that comprises beginning flag, address field, control field, information field, Frame Check Sequence field and termination flag, to form the second class frame; By the transmission priority of the professional code-point defined of segmentation, the second class frame is mapped in the mode towards eight hytes on the virtual container of single Synchronous Optical Network or the cascade channel formed by the virtual container of a plurality of Synchronous Optical Networks on.

2. adaptation method as claimed in claim 1, the service access point identifier of the described second class frame is corresponding to address field or be inserted on two the information field bytes of the most close control field.

3. adaptation method as claimed in claim 1, described cascade channel is by the virtual container of two or more same rates with the Synchronous Optical Network in path, be A1, A2, form to An, the bit-order of mapping is: the 1st bit of virtual container A1, the 1st bit of virtual container A2, the 1st bit of virtual container A3 is to the 1st bit of virtual container An, the 2nd bit of virtual container A1, the 2nd bit of virtual container A2, the 2nd bit of virtual container A3 is to the 2nd bit of virtual container An, N bit to virtual container A1, the N bit of virtual container A2, the N bit of virtual container A3 is to the N bit of virtual container An, and the maximum number bits of each virtual container is the value of ANSI T1.105 defined.

4. adaptation method as claimed in claim 1, the virtual container of described Synchronous Optical Network and the bandwidth after the cascade thereof, payload parameter are:

Virtual container--4 its bandwidth 150336 kilobits/second payloads 149760 kilobits/second

Its bandwidth 601304 kilobits/second payloads 599040 kilobits/second of virtual container--4-4c

Its bandwidth 2405376 kilobits/second payloads 2396160 kilobits/second of virtual container--4-16c

Its bandwidth 9,621 504 kilobits/second payloads 9584640 kilobits/second of virtual container--4-64c

5. adaptation method as claimed in claim 1, use be not confirm formula information transfer service pattern, have only a key element SDH (Synchronous Digital Hierarchy) Link Access Procedure at the 2nd layer, do not have flow control, do not carry out the operation of any affirmation formula yet.

6. adaptation method as claimed in claim 1, after Frame Check Sequence calculating was finished, transmit leg was checked the entire frame content between two flag of frame, when whenever running into " 0 * 7e " it is replaced with " 0 * 7d; 0 * 5e ", when whenever running into " 0 * 7d " it is replaced with " 0 * 7d, 0 * 5d "; The recipient, before calculating Frame Check Sequence, as long as run into " 0 * 7d, 0 * 5e " or " 0 * 7d, 0 * 5d " then does opposite conversion.

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