JP2000078154A - Internet Traffic Handling System in ATM - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a system that realizes CoS guarantee even in an ATM network and enables Internet traffic control. SOLUTION: A VC mapping mechanism 301 determines a VC according to a type of a connection interface or the like when a type of a service category of an IP packet is a band guarantee type. Co
When the type of service category of the IP packet is the best-effort type, the S monitor 302 indicates a CoS attribute indicating whether to transmit or discard the IP packet based on field information indicating transmission / drop priority or information such as an IP address. decide. CLAD mechanism 303 is IP
Convert the packet to an ATM cell and change the CoS attribute to the ATM cell.
Set to cell. The cell switching mechanism switches the ATM cells according to the CoS attribute. CoS control of Internet traffic is performed on an ATM cell basis based on the CoS attribute.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an ATM (Asynchrono
The present invention relates to a system for handling Internet traffic in an ATM that enables control of Internet traffic even within a network.

[0002]

2. Description of the Related Art In an ATM, an ATM service category is assigned in VC (Virtual Channel) units, and QoS (Quality Of Service) is guaranteed in VC units. As ATM service categories, the ATM Forum uses CBR (Constant Bit Rate) and rtVBR (Real Time Varia
ble Bit rate), nrtVBR (Not Real Time Variable Bitra)
te), ABR (Available Bit Rate), UBR (Unspecified Bit
Rate) traffic type.

The functions of each ATM service category are as follows. * CBR: Guaranteed bandwidth and real-time guarantee (guarantee type) * rtVBR: Real-time guaranteed, bandwidth guaranteed at average rate * nrtVBR: No real-time guaranteed, bandwidth guaranteed at average rate * ABR: Best-effort type without guaranteed bandwidth, feedback rate With control * UBR: Best effort type, no feedback rate control

[0004] FIG. 11 is a diagram showing Q in VC unit in an ATM switch.
FIG. 4 is an explanatory diagram showing oS guarantee. In FIG. 11, 1101
Is an ATM switch. As shown in FIG. 11, when transmitting and receiving traffic, the ATM layer user determines which service category the traffic belongs to, and assigns a VC individually by specifying the corresponding service category. ATM switches are used during ATM cell switching.
It is common to have an SC guarantee mechanism that guarantees a service category (hereinafter sometimes abbreviated as SC) in VC units.

On the other hand, the QoS guarantee of the Internet is RSVP
(Resource Reservation Protocol) and CoS (Class of Serv
ice) is often described separately. * RSVP: A protocol for reserving bandwidth for IP flows, and achieves bandwidth guarantee equivalent to ATM CBR / rtVBR / nrtVBR. * CoS: Guarantee the transmission priority and discard priority for each IP packet.

In the CoS control, it is necessary to dynamically determine the transmission / discard priority of an IP packet. For this purpose, the following information is used. * TOS field: An IP packet has a TOS (Type of Service) field indicating transmission / discard priority. * Port number: TCP / U transferred by IP packet
The DP protocol has a port number for identifying an application protocol such as Telnet / FTP / HTTP.
If you want to specify default send and drop priorities for application protocols, you can use port numbers. * IP address: An IP packet has an IP address that specifies the source and destination of traffic. If you want to specify the sending / dropping priority for the traffic source and destination, you can use the IP address.

[0007] CoS control can work for general Internet traffic with best-effort attributes. RSVP provides bandwidth guarantee that is completely opposite to the best-effort concept.
This is the concept of connection base (IP flow is equivalent to connection) similar to. Fig. 12 shows QoS in router
Fig. 2 shows a conceptual diagram of guarantee. In FIG. 12, reference numeral 1201 denotes a router.

[0008] Internet traffic is transmitted over an ATM network through an ATM edge switch (an edge switch is a switch located at the edge of the network and directly connected to a user terminal or the like) or an ATM router (located in the network). In this case, the ATM edge switch or ATM router needs to map (convert) the Internet QoS to the ATM QoS.

The IP flow whose bandwidth is guaranteed by the RSVP control is the AT flow
It can be mapped to M CBR / VBR VC. Also,
General IP traffic whose bandwidth is not guaranteed is mapped to one VC of UBR or ABR of the ATM service category, which is the best-effort type. FIG. 13 shows an example of service category mapping when Internet traffic is transmitted over an ATM network. In FIG. 13, reference numeral 1101 denotes an ATM switch;
01 is a router, and 1301 is an ATM edge switch.

[0010]

As shown in FIG.
QoS guarantee by RSVP can be guaranteed by QoS of ATM. However, there is no mechanism equivalent to CoS control functioning for the Internet's best-effort traffic inside the ATM network, and CoS guarantee cannot be realized. (In ATM, once a connection is established, QoS guarantee such as functioning CoS cannot be realized).

Therefore, as a result, in the ATM network, all the best effort traffic is uniformly handled at the same level. In the current Internet, CoS guarantee needs are higher than bandwidth guarantee mechanisms such as RSVP.
It is considered to be a hindrance to introducing ATM equipment.

The present invention has been made to solve such a problem.
The purpose is to build a system that realizes oS guarantee and enables Internet traffic control.

[0013]

According to a first aspect of the present invention, there is provided a system for handling Internet traffic in an ATM, wherein when a service category of an IP packet is a first type such as a guaranteed bandwidth type, a type of connection interface or the like is provided. VC mapping means for determining a VC to be used in accordance with the above, dynamically recognizing the type of the service category of the IP packet, and when the type of the service category of the IP packet is a second type such as a best effort type, A CoS attribute that determines a CoS attribute indicating a priority, such as whether the IP packet is preferentially transmitted or discarded, based on field information indicating a transmission / discard priority and information such as an IP address and a port number indicating an application protocol. Determining means; Is converted into M cells, and CoS attribute setting means for setting the CoS attribute to the ATM cells,
Cell switching means for switching the ATM cell in accordance with the CoS attribute, wherein the CoS control of Internet traffic is performed in ATM cell units based on the CoS attribute.

[0014] Further, the Internet traffic handling system in the ATM according to the second invention comprises:
The cell switching means has a cell queue for each first type service category, has a plurality of different transmission priorities for each second type service category, and has a cell queue for each transmission priority unit. .

[0015] Further, the Internet traffic handling system in the ATM according to the third invention comprises:
The cell switching means has a plurality of different transmission priorities for each service category of the second type, and has a cell queue for each transmission priority unit.

[0016] Further, a system for handling Internet traffic in an ATM according to a fourth invention comprises:
The CoS attribute setting means dynamically recognizes the CoS of the IP packet, sets the CoS attribute on the ATM cell, and the switching means
Switching is performed according to the CoS attribute of the ATM cell.

Further, the Internet traffic handling system in the ATM according to the fifth invention comprises:
The CoS attribute determining means determines the information such as the minimum delay, the maximum throughput, the maximum reliability, and the minimum monetary cost, which are defined by the field information, and a plurality of types of Cos corresponding thereto.
It holds table information in which the S attribute is registered.

Further, the Internet traffic handling system in the ATM according to the sixth invention comprises:
The CoS attribute determining means holds field information corresponding to each type of ATM service category and table information in which CoS information is registered.

Further, the Internet traffic handling system in the ATM according to the seventh invention comprises:
The CoS attribute setting means sets the CoS attribute to V in the ATM cell header.
This is set in the PI area.

An Internet traffic handling system in an ATM according to an eighth aspect of the present invention comprises:
The CoS attribute setting means sets the CoS attribute to V in the ATM cell header.
This is set in the CI area.

The Internet traffic handling system in the ATM according to the ninth invention comprises:
The CoS attribute setting means sets the CoS attribute to the P in the ATM cell header.
This is set in the TI area.

Further, in the Internet traffic handling system in the ATM according to the tenth invention, the CoS attribute setting means sets the CoS attribute in a payload area of the ATM cell.

The Internet traffic handling system in an ATM according to the eleventh invention is a CoS attribute determining means for determining CoS attributes such as a transmission priority and a discard priority from field information of an IP packet, an IP address and a port number. And the service category of the IP packet and the above CoS
VC mapping means for determining a VC to be used according to the type of attribute; packet converting means for converting the IP packet into an ATM cell; and cell switching means for exchanging the ATM cell according to the VC.
VC with S attribute added to ATM service category attribute
Attribute.

Further, in the Internet traffic handling system in the ATM according to the twelfth invention, the VC mapping means specifies a VC having a different CoS attribute such as a transmission priority and a discard priority in addition to a service category when setting a connection. Things.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 AT, including conventional examples
Best effort traffic C in M network
The concept that the mechanism to guarantee oS cannot be realized is that this concept is
Is inconsistent with the basic concept shown below. * With ATM QoS, best effort traffic is
It is handled as one service category such as UBR / ABR. However, ATM has no concept of QoS inside best effort. On the other hand, Internet traffic is basically best-effort traffic, and among them, QoS called CoS exists. * The ATM service category is a static concept tied to VC. In other words, ATM QoS works on a VC basis. On the other hand, Internet CoS is realized by dynamic priority control within one connectionless link.

Therefore, in order to realize the CoS guarantee in the ATM network, it is necessary to modify the ATM concept.

FIG. 1 is a block diagram showing one embodiment of an Internet traffic handling system according to the present invention, and shows an example in which cell-based CoS control is incorporated in an ATM switch. In the figure, 101 is A
A TM switch, 102 is a router, and 103 is an ATM edge switch.

In this embodiment, in order to eliminate inconsistency between the basic concepts related to the QoS of ATM and the Internet, A
Introduce cell-based CoS control instead of VC-based in TM.
Therefore, the following measures are taken in this embodiment. * In addition to the existing QoS of ATM, which was considered for VC binding, a concept equivalent to Internet CoS will be introduced in a VC-independent manner. * ATM allows CoS to be specified in ATM cell units, as CoS was specified in IP packet units. (This mechanism is independent of the existing ATM QoS, so it works inside best-effort traffic.) * CoS can basically specify the priority such as transmission priority and discard priority, and specify the bandwidth. No function. (If you want to reserve bandwidth, use the existing ATM
(Using QoS mechanism) * There are various methods to specify CoS for each ATM cell.
There are also various realization methods for guaranteeing the transmission priority and the discard priority. * In order to guarantee QoS, there is no need to set up individual VCs with that QoS attribute, and effective use of resources is possible.

When the cell-based CoS control as described above is incorporated in an ATM switch, as shown in FIG.
QoS and ATM QoS can be mapped seamlessly. Accordingly, the ATM can handle the Internet CoS.

Embodiment 2 FIG. Embodiment 1 shown in FIG.
Then, the ATM edge switch dynamically recognizes the CoS of the IP packet and sets the CoS attribute on the ATM cell. Each ATM switch operates according to the CoS attribute of the ATM cell.

FIG. 2 is a block diagram showing an embodiment of an Internet traffic handling system according to the present invention, showing an example in which VC-based CoS control is incorporated in an ATM switch. In the figure, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts.

In this embodiment, the ATM-based QoS control concept of ATM is extended in order to eliminate inconsistencies between the basic concepts of ATM and Internet QoS. * The transmit / drop priority equivalent to CoS control is
Make it possible to specify it as a sub-attribute of ATM QoS such as / ABR and statically tie it to VC. (CoS control works inside best-effort traffic) * To secure the bandwidth, the existing ATM QoS mechanism is used, and a concept equivalent to CoS control is not introduced. * The transmission / drop priority can be dynamically specified at connection setup by extending the SVC setup procedure. * It is necessary to set multiple VCs for multiple transmission / drop priority, but as with cell-based CoS control, A
There is no need to extend the meaning of the TM cell header independently.

Even if the above-described VC-based CoS control is incorporated in an ATM switch, as shown in FIG.
QoS and ATM QoS can be mapped seamlessly.

In FIG. 2, the ATM edge switch dynamically recognizes the CoS of the IP packet and transmits the IP packet on a VC having a mappable CoS attribute. Each ATM switch operates according to the CoS attribute of the VC.

Embodiment 3 FIG. FIG. 3 shows an ATM according to the present invention.
FIG. 6 is an overall configuration diagram of an ATM edge switch showing another embodiment of the Internet traffic handling system in FIG. In the figure, reference numeral 301 denotes an IP packet.
VC mapping mechanism for mapping to ATM VC, 302 is I
CoS monitor for determining CoS attribute of P packet, 303
Is CLAD (Cell Assembly Deassembly) mechanism, 304 is A
A cell switching mechanism for exchanging TM cells, 305 is an output port.

The VC mapping mechanism 301 maps IP packets to ATM VCs according to various standards.
If the edge interface is a serial line or Ethernet that handles IP packets, IP over ATM (RFC
1490) or MPOA (defined by ATM FORUM: Multicast Prot)
ocol Over ATM). If the edge interface is a frame relay, it conforms to FR-ATM interwork (FRF.5). Also, if the edge switch is R
When terminating SVP, RSVP currently being discussed in IETF etc.
Over ATM specifications shall be followed.

As an example, IP over A operating on a PVC basis
When conforming to the TM specification, the VC corresponding to the IP address is determined from the correspondence table in Table 1. IP over SVC based
In the case of ATM, UNI 3.1 which is the standard signaling of ATM
And the like, the VC connection is dynamically set, and the correspondence table in Table 1 is also dynamically updated. Table 1 when the edge interface is a frame relay.
Instead of the IP address and output port / VPI / VC correspondence table as shown in the figure, DLCI (data link channel ID) and output port
It is assumed that a correspondence table of / VPI / VC has been created.

[0038]

[Table 1]

The CoS monitor 302 has a TOS field and IP
Determine CoS attribute from address, port number, etc. CLA
The D mechanism 303 has a function of setting CoS information in an ATM cell, in addition to a function of converting an IP packet into an ATM cell and a function of decelerating the IP packet.

The cell switching mechanism 304 includes a cell switching mechanism for exchanging cells between an input port and an output port based on a VPI / VCI set in an ATM cell, and a QoS guarantee mechanism (SC
Guarantee mechanism and cell-based CoS control mechanism).

When the cell switching mechanism outputs a cell to an output port, ATM cells are temporarily stored in a cell queue. In general, a QoS guarantee mechanism functions when a cell is output from a cell queue to an output port.

In the present embodiment, for example, a QoS guarantee mechanism is realized by the queuing system shown in FIG.
FIG. 4 shows a case where nine cell queues exist for each output port (the cell queue may be a virtual case). Then, different transmission priorities are assigned to the respective cell queues.

After the cell exchange mechanism exchanges cells between the input port and the output port based on the VPI / VCI, the ATM cells are stored in one of the cell queues set for the output port. The cell queue is determined from the service category of the VC connection that transmitted the cell, and CoS information set in the ATM cell when the service category is ABR / UBR. The QoS guarantee mechanism outputs a cell to an output port using, for example, a queue selection algorithm described below. * Basically transmit the cell in the high priority cell queue first. * For the cell queues of CBR, rtVBR, and nrtVBR, set the number of cells that can be transmitted during a fixed period. When the number of transmission cells reaches this set value, no output is performed even if cells are queued in the cell queue, and control is transferred to the next priority cell queue. * If there are no cells in the cell queues of CBR, rtVBR and nrtVBR, or if the output from these cell queues reaches the upper limit of the number of transmittable cells, the cell is output from the cell queue of UBR / ABR. * Cell output from the UBR / ABR cell queue is also processed in order from the cell queue with the highest priority. CoS by this mechanism
Transmission priority can be realized.

As shown in FIG. 4, a cell discard threshold can be set for each cell queue, and when the queuing number exceeds the threshold, cell discard is performed. By providing three levels of thresholds of H / M / L as thresholds for discarding cells in the cell queue of UBR / ABR, it is possible to realize CoS discard priority.

Embodiment 4 FIG. 5 shows an ATM according to the present invention.
Edge switch 1 showing another embodiment of the Internet traffic handling system in the ATM
FIG. 3 is an overall configuration diagram of FIG. 3, and the same reference numerals in FIG. 501 is an input port and 502 is an output port. The ATM edge switch 103 is mainly configured by a cell switching mechanism having both an SC guarantee mechanism and a cell-based CoS control mechanism. This function is completely the same as that of the ATM edge switch. In the present embodiment, the CoS is considered to be finally interpreted as a transmission priority and a discard priority. Here, an embodiment for expressing this CoS will be described.

When performing TOS field mapping, the IP
The TOS field (4 bits) set in the address is regarded as CoS information. Finally, the TOS field is interpreted as a three-step transmission priority and a three-step discard priority according to, for example, Table 2.

[0047]

[Table 2]

In the TOS field mapping, CoS information requires 4 bits, but is set in the ATM cell header.
In some cases, many bits are not avoided as a field of CoS information. In this case, the CoS information is transmitted in two stages of transmission priority (H / L) or two stages of discard priority (H / L).
L) may be represented by one bit.

In particular, in the VC mapping, when the output port / VPI / VC is determined as shown in Table 1, the ATM service category is also determined. For example, the system may be defined such that the default TOS is automatically determined as shown in Table 3 when the ATM service category is determined.

[0050]

[Table 3]

In order to specify the CoS for each ATM cell, the VPI area of the ATM cell header is used. In Fig. 6, TOS is added to CoS information.
Assume that field mapping is performed. * It is virtually impossible for the system to use up one byte of VPI (two bytes on the network side).

In order to specify the CoS for each ATM cell, the VCI area of the ATM cell header is used. In Fig. 7, TOS is added to CoS information.
Assume that field mapping is performed. * ATM megalink services currently offered by carriers
(NTT), etc. are mostly VP lending services and VCI
The area is Don ■ t Care. Therefore, no problem occurs even if the VCI area is used independently. * There is virtually no network configuration that uses up the two bytes of the VCI as a system.

In order to specify CoS for each ATM cell, the PTI area of the ATM cell header is used. In FIG. 8, it is assumed that the minimum mapping is performed on the CoS information. * When the ATM cell is a user information cell, the upper 1 bit of the PTI field is an unused area. * The transmission priority or discard priority is expressed by one bit. Which priority is meant by the system is configured.

In order to specify CoS for each ATM cell, the payload area of the ATM cell is used. In FIG. 9, TOS is added to CoS information.
Assume that field mapping is performed. * Although the efficiency is reduced because it is set in the payload, the idea works even through an existing ATM switch because the ATM header conforms to the standard.

FIG. 10 shows an example of the overall configuration of an ATM edge switch that implements VC-based CoS control. In FIG.
3 denote the same or corresponding parts.

The CoS monitor determines the transmission priority and the discard priority from the TOS field, IP address, port number and the like. In the VC-based CoS control, the CoS information is not set in the ATM cell, so that there is not much meaning in expressing the information.

The VC mapping mechanism is a mechanism for mapping IP packets to ATM VCs according to various standards. The basic mechanism is the same as the cell-based mechanism, except for the following points. * Prepare multiple ATM VCs for UBR / ABR with attributes with different transmission priority and discard priority. * In addition to the VC selection function based on IP address, etc., a function to select a VC according to the transmission priority and discard priority determined by the CoS monitor is added. (In the VC selection phase by IP address etc., multiple VCs will be selected)

The attributes (transmission priority and discard priority) of each VC need to be negotiated with the cell switching mechanism in advance.

It is to be noted that, by adding a function of designating a VC having a different transmission priority and a different discard priority in addition to a service category to a signaling protocol such as ATM UNI3.1, a VC connection having a transmission priority and a discard priority is activated. Can also be set manually.

The CLAD mechanism needs only the basic function of converting an IP packet into ATM cells and decellularizing.

Cell switching mechanism The basic mechanism is the same as the cell-based mechanism, except for the following. * Cell queue selection is uniquely determined from the VC connection that sent the cell. * Therefore, one transmission priority and discard priority are assigned as attributes of the cell queue. Therefore, this cell queue has only one discard threshold (priority) together with only one transmission priority.

[0062]

According to the first aspect of the present invention, since the CoS control of the Internet traffic is performed in the unit of the ATM cell, there is an effect that the CoS of the Internet can be handled even in the ATM network.

According to the second invention, the cell switching means has a cell queue for each first type service category, and has a plurality of different transmission priorities for each second type service category. Since a cell queue is provided for each credit priority, it is possible to flexibly respond.

According to the third aspect, the cell switching means has a plurality of different transmission priorities for each service category of the second type, and has a cell queue for each transmission priority unit. It has the effect that it becomes possible.

According to the fourth aspect, the CoS attribute setting means dynamically recognizes the CoS of the IP packet, sets the CoS attribute on the ATM cell, and the switching means switches according to the CoS attribute of the ATM cell. , CoS attributes can be dynamically set.

According to the fifth aspect, the CoS attribute determining means determines the minimum delay meaninged by the field information,
Since information such as the maximum throughput, the maximum reliability, and the minimum monetary cost, and table information in which a plurality of types of CoS attributes corresponding to the information are stored, the CoS attribute determining means determines the minimum delay, maximum throughput, There is an effect that a plurality of types of CoS attributes can be automatically generated based on the importance of information such as maximum reliability and minimum money cost.

According to the sixth aspect, the CoS attribute determining means retains field information and table information in which CoS information is registered for each type of ATM service category, so that the ATM service category is determined. This has the effect that the default CoS attribute is automatically determined.

According to the seventh aspect, since the CoS attribute setting means sets the CoS attribute in the VPI area of the ATM cell header, there is an effect that CoS control can be performed on a cell basis.

According to the eighth aspect, since the CoS attribute setting means sets the CoS attribute in the VCI area of the ATM cell header, there is an effect that CoS control can be performed on a cell basis.

According to the ninth aspect, since the CoS attribute setting means sets the CoS attribute in the PTI area of the ATM cell header, there is an effect that cell-by-cell CoS control becomes possible.

According to the tenth aspect, since the CoS attribute setting means sets the CoS attribute in the payload area of the ATM cell, there is an effect that CoS control can be performed on a cell basis.

According to the eleventh aspect, the CoS attribute is set to AT
Since the attribute of the VC is used in addition to the attribute of the service category of M, there is an effect that the CoS of the Internet can be handled even in the current standard ATM network.

According to the twelfth aspect, the VC mapping means, when setting the connection, includes not only the service category but also the transmission priority and the discarding priority such as the transmission priority and the discarding priority.
Since VCs with different oS attributes are specified, there is an effect that a VC connection based on a service category including CoS can be dynamically set.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing cell-based Cos control.

FIG. 2 is an explanatory diagram showing VC-based Cos control.

FIG. 3 is an overall configuration diagram of an ATM edge switch.

FIG. 4 is an explanatory diagram of a cell switching mechanism provided with a queuing system for realizing a QoS guarantee mechanism.

FIG. 5 is a configuration diagram illustrating an overall configuration example of an ATM edge switch.

FIG. 6 shows NNIs and UNs for which Cos information is set.
3 is a diagram illustrating an example of an ATM header structure of I. FIG.

FIG. 7 shows NNIs and UNs for which Cos information is set.
FIG. 10 is a diagram showing another example of the ATM header structure of I.

FIG. 8 shows NNIs and UNs for which Cos information is set.
FIG. 10 is a diagram showing another example of the ATM header structure of I.

FIG. 9 shows NNIs and UNs for which Cos information is set.
FIG. 10 is a diagram showing another example of the ATM header structure of I.

FIG. 10 is an overall configuration diagram of an ATM edge switch.

FIG. 11 is an explanatory diagram showing QoS guarantee in VC units in an ATM switch.

FIG. 12 is an explanatory diagram showing QoS guarantee for each IP in a router.

FIG. 13 is an explanatory diagram showing an example of mapping to service categories when transmitting Internet traffic over an ATM network.

[Explanation of symbols]

 101 ATM switch 102 Router 103 ATM edge switch 301 VC mapping mechanism 302 CoS monitor 303 CLAD mechanism 304 Cell switching mechanism 305 Output port 501 Input port 502 Output port 1101 ATM switch 1201 Router 1301 ATM edge switch

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroshi Takeda 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) in Mitsubishi Electric Corporation 5K030 GA11 HA10 HB14 HB17 HC01 JA06 KX11 LA03 LC18 LE05

Claims (12)

[Claims] 1. An IP (Internet Protocol)
ol) When the type of the service category of the packet is the first type such as the guaranteed bandwidth type, a VC (Virtual Channel) used according to the type of the connection interface or the like.
e) determining dynamically the type of the service category of the IP packet,
In the case where the type of service category of the P packet is the second type such as the best effort type, the IP packet is prioritized based on field information indicating transmission / discard priority and information such as an IP address and a port number indicating an application protocol. CoS (Class) indicating the priority such as whether to transmit or discard
of Service (CoS) attribute determining means for determining an attribute of the service, and transmitting the IP packet to an ATM (Asynchronous
No. Transfer Mode) CoS to convert the cell into a cell and set the CoS attribute to the ATM cell.
An attribute setting means; and a cell switching means for switching the ATM cell according to the CoS attribute, wherein the CoS control of the Internet traffic is performed on an ATM cell basis based on the CoS attribute.・ Traffic handling system. 2. The cell switching means comprises a cell queue for each service category of a first type,
2. The Internet traffic handling system according to claim 1, wherein a plurality of different transmission priorities are provided for each second type of service category, and a cell queue is provided for each transmission priority unit. 3. The ATM according to claim 1, wherein the cell switching means has a plurality of different transmission priorities for each service category of the second type, and has a cell queue for each transmission priority unit. Internet traffic handling system. 4. A CoS attribute setting means, comprising:
2. The system for handling Internet traffic in ATM according to claim 1, wherein S is dynamically recognized, a CoS attribute is set on the ATM cell, and the switching means performs switching according to the CoS attribute of the ATM cell. 5. The CoS attribute determining means includes: a minimum delay, a maximum throughput,
2. The Internet traffic handling system according to claim 1, wherein the system has information such as maximum reliability and minimum money cost and table information in which a plurality of types of CoS attributes corresponding to the information are registered. 6. The CoS attribute determining means includes: a field information corresponding to each type of an ATM service category;
2. The ATM according to claim 1, wherein table information in which oS information is registered is held.
Traffic handling system. 7. The CoS attribute setting means sets the CoS attribute to AT
2. The Internet traffic handling system according to claim 1, wherein the system is set in a VPI area of an M cell header. 8. The CoS attribute setting means sets the CoS attribute to AT
2. The Internet traffic handling system according to claim 1, wherein the system is set in a VCI area of an M cell header. 9. The CoS attribute setting means sets the CoS attribute to AT
2. The Internet traffic handling system according to claim 1, wherein the system is set in a PTI area of an M cell header. 10. The CoS attribute setting means sets the CoS attribute.
2. The system for handling Internet traffic in ATM according to claim 1, wherein the system is set in a payload area of an ATM cell. 11. Field information and IP of an IP packet
CoS attribute determining means for determining CoS attributes such as transmission priority and discard priority from addresses and port numbers, and VC mapping means for determining a VC to be used according to the service category of the IP packet and the type of the CoS attribute. Packet conversion means for converting the IP packet into an ATM cell; and cell switching means for exchanging the ATM cell in accordance with the VC, wherein the CoS attribute is a VC attribute in addition to the ATM service category attribute. Internet traffic handling system in ATM. 12. The VC mapping means, when a connection is set, a VC having a different CoS attribute such as a transmission priority and a discard priority in addition to a service category.
The system for handling Internet traffic in an ATM according to claim 11, wherein: