Well, the material of the study of today's chief telecommunications engineer is an ATM, too. The ATM and the adaptation layer call AAL for short today. AAL is a layer that hits the sub-layer in OSI reference model's data link layer. When you allow me to quote the explanation of the type of AAL from Wiki easily
AAL1 connection type and constant bit rate. Standard for communication of mass animation such as video conferencing telephones. To use one octet of payloads for the control of the order of transmitting the cell, real data becomes 47 octets. It is used in premises LAN.
AAL2 connection type and variable bit rate. Standard for low-speed voice sign. It is allowed to multiplex two or more traffic to one cell to decrease jitter's (swing the delay) influence by assembly and the restoration of the cell, and to send before the cell is filled.
AAL3/4 connectionless type and constant bit rate. Standard for for data communication. AAL3 and AAL4 were integrated by moving the connection setting to a high-ranking layer though it originally proposed AAL3 as a connection type and AAL4 was proposed as a connectionless type. To use four octets of payloads for high-ranking layer PDU information, real data becomes 44 octets.
AAL5 connectionless type and variable bit rate. Standard by which AAL3/4 is simplified. All payloads can be used for real data by assuming a positional detecting function of a high-ranking layer to be only a finality part. It is widely used as large area LAN with Ethernet over ATM, IP over ATM, and PPPoA (Point-to-Point Protocol over ATM). ･･･. It is so. Then, it is based and today's material is [kochira] ↓↓.
- ATM adaptation layer (AAL)
The leased circuit service etc. are used to communicate on the ATM network being classified into service class A pseudo.. resemblance of existing line service for the communication of the fixed speed type. AAL type 1
These sentences are correct.
- AAL type 1 It communicates like the leased circuit service etc. on the ATM network being classified into service class A for the communication = fixed speed type by pseudo.. resemblance of existing line service.
AAL type 2 is used to communicate of the real time character's at a changeable speed not being demanded ..for a low-speed voice-data communication...
These sentences are wrong.
- AAL type 2 is for a low-speed voice-data communication, and real time AAL for the communication from which the character is demanded at a changeable speed.
- Type 2 is low-speed though type 1 is a fixed speed at a changeable speed ･･･ However, the character is in real time demanded naturally because it uses it for the voice-data communication.
AAL type 3/4 is hardly used from becoming of AAL type 5 with few overheads or more the main current for the data communication for the data communication.
These sentences are correct.
- The AAL type is hardly used from becoming of AAL type 5 with few overheads or more the main current for the data communication for 3/4= data communication.
Isn't today's problem comparatively comprehensible?However, correct sentences that become livers of the layer, changing sentences for a moment in the part like "Extra", and setting questions do doing by being ･･･ Then, around here today
Showing posts with label ATM. Show all posts
Showing posts with label ATM. Show all posts
2010/09/21
About VP and VC of the ATM
Yes, I think that today's chief telecommunications engineer's material also goes by the ATM. In today's problem, virtual passing VC is a virtual channel in VP in VP and VC of the ATM. Is VP (virtual pass) a virtual transmission line in short and it only have to be thought the transmission line of the ATM and SDH?It is a group of a logical virtual line that mutually connects the edge tune. VC (virtual channel) is a road to put it briefly as shown in data. A few VC can be passed through one VP and good transmission of efficiency can be done. Then, today's material is [kochira] ↓↓.
- VP of ATM (virtual passing) and VC (virtual channel)
In the sending terminal, the VCI value in which the receiving terminal that is the address is indicated directly is set to the VCI field of the ATM cell.
These sentences are wrong.
- VCI doesn't indicate the address directly. VCI decentralization only arranges and is used only to distinguish the channel that each cell belongs in the done each switch.
- Only the VCI value shows the channel, and even the terminal is not shown.
In the method of setting VC, there is PVC method set like the SVC method and the lease line, etc. of the setting at each communication based on the contract.
These sentences are correct.
- Method of setting only SVC = to communicate, and liberating virtual channel with end of communication
- Method of assuming virtual channel to be to be remain set for a long term by PVC = contract etc.
In the ATM network where the VP crossing connection was used, VC is set with the ATM switch in the terminal of VP.
These sentences are correct.
- Naturally, the setting of VC is a switch in the terminal of VP.
VC accommodated by VP besides VC accommodated by a certain VP of the output port of the ATM switch can use the same VCI value.
These sentences are correct.
- Yes, it is possible to use it.
さて、いかがでしたか？明日からの週末も気を抜かずに伝送交換の勉強がんばってくださいね。それでは今日はこの辺で。
- VP of ATM (virtual passing) and VC (virtual channel)
In the sending terminal, the VCI value in which the receiving terminal that is the address is indicated directly is set to the VCI field of the ATM cell.
These sentences are wrong.
- VCI doesn't indicate the address directly. VCI decentralization only arranges and is used only to distinguish the channel that each cell belongs in the done each switch.
- Only the VCI value shows the channel, and even the terminal is not shown.
In the method of setting VC, there is PVC method set like the SVC method and the lease line, etc. of the setting at each communication based on the contract.
These sentences are correct.
- Method of setting only SVC = to communicate, and liberating virtual channel with end of communication
- Method of assuming virtual channel to be to be remain set for a long term by PVC = contract etc.
In the ATM network where the VP crossing connection was used, VC is set with the ATM switch in the terminal of VP.
These sentences are correct.
- Naturally, the setting of VC is a switch in the terminal of VP.
VC accommodated by VP besides VC accommodated by a certain VP of the output port of the ATM switch can use the same VCI value.
These sentences are correct.
- Yes, it is possible to use it.
さて、いかがでしたか？明日からの週末も気を抜かずに伝送交換の勉強がんばってくださいね。それでは今日はこの辺で。
2010/09/20
ATM adaptation layer
Well, the material of the study of today's chief telecommunications engineer is an ATM, too. The ATM and the adaptation layer are studied today. The ATM adaptation layer is called AAL for short. AAL is a layer that hits the sub-layer in OSI reference model's data link layer.
When I am allowed to quote the explanation of the type of AAL from Wiki easily, it is AAL1 connection type and a constant bit rate. Standard for communication of mass animation such as video conferencing telephones. To use one octet of payloads for the control of the order of transmitting the cell, real data becomes 47 octets. It is used in premises LAN. AAL2 connection type and variable bit rate. Standard for low-speed voice sign. It is allowed to multiplex two or more traffic to one cell to decrease jitter's (swing the delay) influence by assembly and the restoration of the cell, and to send before the cell is filled. AAL3/4 connectionless type and constant bit rate. Standard for for data communication. AAL3 and AAL4 were integrated by moving the connection setting to a high-ranking layer though it originally proposed AAL3 as a connection type and AAL4 was proposed as a connectionless type. To use four octets of payloads for high-ranking layer PDU information, real data becomes 44 octets. AAL5 connectionless type and variable bit rate. Standard by which AAL3/4 is simplified. All payloads can be used for real data by assuming a positional detecting function of a high-ranking layer to be only a finality part. It is widely used as large area LAN with Ethernet over ATM, IP over ATM, and PPPoA (Point-to-Point Protocol over ATM). ･･･. It is so. Then, it is based and today's material is [kochira] ↓↓.
- ATM adaptation layer (AAL
The leased circuit service etc. are used to communicate on the ATM network being classified into service class A pseudo.. resemblance of existing line service for the communication of the fixed speed type. AAL type 1
These sentences are correct.
- AAL type 1 It communicates like the leased circuit service etc. on the ATM network being classified into service class A for the communication = fixed speed type by pseudo.. resemblance of existing line service.
AAL type 2 is used to communicate of the real time character's at a changeable speed not being demanded ..for a low-speed voice-data communication...
These sentences are wrong.
- AAL type 2 is for a low-speed voice-data communication, and real time AAL for the communication from which the character is demanded at a changeable speed.
- Type 2 is low-speed though type 1 is a fixed speed at a changeable speed ･･･ However, the character is in real time demanded naturally because it uses it for the voice-data communication.
AAL type 3/4 is hardly used from becoming of AAL type 5 with few overheads or more the main current for the data communication for the data communication.
These sentences are correct.
- The AAL type is hardly used from becoming of AAL type 5 with few overheads or more the main current for the data communication for 3/4= data communication.
Isn't today's problem comparatively comprehensible?However, correct sentences that become the texts of the layer, changing sentences for a moment in the part like "Extra", and setting questions do doing by being ･･･ Then, around here today
When I am allowed to quote the explanation of the type of AAL from Wiki easily, it is AAL1 connection type and a constant bit rate. Standard for communication of mass animation such as video conferencing telephones. To use one octet of payloads for the control of the order of transmitting the cell, real data becomes 47 octets. It is used in premises LAN. AAL2 connection type and variable bit rate. Standard for low-speed voice sign. It is allowed to multiplex two or more traffic to one cell to decrease jitter's (swing the delay) influence by assembly and the restoration of the cell, and to send before the cell is filled. AAL3/4 connectionless type and constant bit rate. Standard for for data communication. AAL3 and AAL4 were integrated by moving the connection setting to a high-ranking layer though it originally proposed AAL3 as a connection type and AAL4 was proposed as a connectionless type. To use four octets of payloads for high-ranking layer PDU information, real data becomes 44 octets. AAL5 connectionless type and variable bit rate. Standard by which AAL3/4 is simplified. All payloads can be used for real data by assuming a positional detecting function of a high-ranking layer to be only a finality part. It is widely used as large area LAN with Ethernet over ATM, IP over ATM, and PPPoA (Point-to-Point Protocol over ATM). ･･･. It is so. Then, it is based and today's material is [kochira] ↓↓.
- ATM adaptation layer (AAL
The leased circuit service etc. are used to communicate on the ATM network being classified into service class A pseudo.. resemblance of existing line service for the communication of the fixed speed type. AAL type 1
These sentences are correct.
- AAL type 1 It communicates like the leased circuit service etc. on the ATM network being classified into service class A for the communication = fixed speed type by pseudo.. resemblance of existing line service.
AAL type 2 is used to communicate of the real time character's at a changeable speed not being demanded ..for a low-speed voice-data communication...
These sentences are wrong.
- AAL type 2 is for a low-speed voice-data communication, and real time AAL for the communication from which the character is demanded at a changeable speed.
- Type 2 is low-speed though type 1 is a fixed speed at a changeable speed ･･･ However, the character is in real time demanded naturally because it uses it for the voice-data communication.
AAL type 3/4 is hardly used from becoming of AAL type 5 with few overheads or more the main current for the data communication for the data communication.
These sentences are correct.
- The AAL type is hardly used from becoming of AAL type 5 with few overheads or more the main current for the data communication for 3/4= data communication.
Isn't today's problem comparatively comprehensible?However, correct sentences that become the texts of the layer, changing sentences for a moment in the part like "Extra", and setting questions do doing by being ･･･ Then, around here today
2010/09/17
About VP and VC of the ATM
Yes, I think that today's chief telecommunications engineer's material also goes by the ATM. In today's problem, virtual passing VC is a virtual channel in VP in VP and VC of the ATM. Is VP (virtual pass) a virtual transmission line in short and it only have to be thought the transmission line of the ATM and SDH?It is a group of a logical virtual line that mutually connects the edge tune. VC (virtual channel) is a road to put it briefly as shown in data. A few VC can be passed through one VP and ..[] that does good transmission of efficiency.. technique. Then, today's material is [kochira] ↓↓.
- VP of ATM (virtual passing) and VC (virtual channel)
In the sending terminal, the VCI value in which the receiving terminal that is the address is indicated directly is set to the VCI field of the ATM cell.
These sentences are wrong.
- VCI doesn't indicate the address directly. VCI decentralization only arranges and is used only to distinguish the channel that each cell belongs in the done each switch.
- Only the VCI value shows the channel, and even the terminal is not shown.
In the method of setting VC, there is PVC method set like the SVC method and the lease line, etc. of the setting at each communication based on the contract.
These sentences are correct.
- Method of setting only SVC = to communicate, and liberating virtual channel with end of communication
- Method of assuming virtual channel to be to be remain set for a long term by PVC = contract etc.
In the ATM network where the VP crossing connection was used, VC is set with the ATM switch in the terminal of VP.
These sentences are correct.
- When it curves, the setting of VC might be a switch in the terminal of VP.
VC accommodated by VP besides VC accommodated by a certain VP of the output port of the ATM switch can use the same VCI value.
These sentences are correct.
- Yes, it is possible to use it.
Well, how?It studies and the transmission exchange holds out without pulling out the nature on the weekend from tomorrow. Then, around here today.
- VP of ATM (virtual passing) and VC (virtual channel)
In the sending terminal, the VCI value in which the receiving terminal that is the address is indicated directly is set to the VCI field of the ATM cell.
These sentences are wrong.
- VCI doesn't indicate the address directly. VCI decentralization only arranges and is used only to distinguish the channel that each cell belongs in the done each switch.
- Only the VCI value shows the channel, and even the terminal is not shown.
In the method of setting VC, there is PVC method set like the SVC method and the lease line, etc. of the setting at each communication based on the contract.
These sentences are correct.
- Method of setting only SVC = to communicate, and liberating virtual channel with end of communication
- Method of assuming virtual channel to be to be remain set for a long term by PVC = contract etc.
In the ATM network where the VP crossing connection was used, VC is set with the ATM switch in the terminal of VP.
These sentences are correct.
- When it curves, the setting of VC might be a switch in the terminal of VP.
VC accommodated by VP besides VC accommodated by a certain VP of the output port of the ATM switch can use the same VCI value.
These sentences are correct.
- Yes, it is possible to use it.
Well, how?It studies and the transmission exchange holds out without pulling out the nature on the weekend from tomorrow. Then, around here today.
2010/09/16
OAM function of ATM layer
Well, today's chief telecommunications engineer's material is an ATM. They are problems of behavior and the operation, etc. of the OAM cell this time though the OAM cell calls the cell that transmits information on the maintenance operation management in the cell of the ATM. Then, today's material is [kochira] ↓↓.
- OAM function of ATM layer
The warning transfer function is achieved by sending the OAM cell that displays the breakdown to VP and VC from the device that detects the breakdown of a physical layer or the ATM layer.
These sentences are correct.
- The warning transfer function: The breakdown notification is done by sending the OAM cell (AIS cell and RDI cell) that displays the breakdown to VP or VC from the device that detects the breakdown of a function, a physical layer or the ATM layer that notifies VP and VC not to be able to be used when the breakdown occurs in the transfer function of a physical layer or the ATM layer.
VP-RDI: Signal that is judged breakdown, and sent at transmitting end when user information cell or OAM cell doesn't receive it on receiving side longer than fixed time
Signal to notify direction of reception side from the connection point the breakdown when breakdown of VP-AIS:VP connection is detected
The loop back cell that receives it is sent back as it is in the device specified for a halfway mark though the connection of the communication of a specified section of arbitrary VP and VC confirmation uses the loop back function.
These sentences are wrong.
- The OAM cell for the loop back is sent from the device on the edge of the section where it wants to confirm the communication connection. The number of the device on the other edge is written in the loop back cell as a halfway mark. This loop back cell is sent in the counter direction when received with the device for which the loop back cell is specified for a halfway mark. The communication connection in a specified section is confirmed first by receiving the turned loop back cell in the device that sends the loop back cell.
- Moreover, the meaning of this explanation is not understood. ｡｡
- Anyway, the part of "Send it back as it is" is a mistake, and "It rewrites in a specific value and send it back" answers correctly.
- The least significant bit of the loop back display field displays whether the loop back has already been executed by the pool algebra form. It is confirmed whether the loop back is executed by this field in the ATM layer. This field is coded to "00000001" in the source point. In the loop back point, it replaces it with "00 million".
The number of cell losses and the number etc. of mistakes of VP and VC can be confirmed on the receiving side according to information on the OAM cell for the continuity check.
These sentences are wrong.
- The number of cell losses and the number etc. of sign mistakes of VP and VC cannot be confirmed by using OAM cell information for the reception side continuity check.
- Anyway, it seems to be "It is not possible to judge on the receiving side. "
The continuity check function and the performance monitoring function start/are stopped by start/stop OAM cell. Which function start/is stopped is specified in peculiar to the function of the payload field.
These sentences are wrong.
- Which function start/is stopped is specified by the OAM function type of the payload.
- Continuity check or performance monitoring function or which is used is specified by "OAM function type".
Well, how about you?It is caught to the problem if it studies really neatly, and it doesn't remember surely if it is necessary to judge the correction from either that rewrites only ending of a words of sentences and sentences that can be taken. Because frequency of setting questions is considerably high, let's work hard and remember the OAM relation in the problem of the ATM. Then, around here today
- OAM function of ATM layer
The warning transfer function is achieved by sending the OAM cell that displays the breakdown to VP and VC from the device that detects the breakdown of a physical layer or the ATM layer.
These sentences are correct.
- The warning transfer function: The breakdown notification is done by sending the OAM cell (AIS cell and RDI cell) that displays the breakdown to VP or VC from the device that detects the breakdown of a function, a physical layer or the ATM layer that notifies VP and VC not to be able to be used when the breakdown occurs in the transfer function of a physical layer or the ATM layer.
VP-RDI: Signal that is judged breakdown, and sent at transmitting end when user information cell or OAM cell doesn't receive it on receiving side longer than fixed time
Signal to notify direction of reception side from the connection point the breakdown when breakdown of VP-AIS:VP connection is detected
The loop back cell that receives it is sent back as it is in the device specified for a halfway mark though the connection of the communication of a specified section of arbitrary VP and VC confirmation uses the loop back function.
These sentences are wrong.
- The OAM cell for the loop back is sent from the device on the edge of the section where it wants to confirm the communication connection. The number of the device on the other edge is written in the loop back cell as a halfway mark. This loop back cell is sent in the counter direction when received with the device for which the loop back cell is specified for a halfway mark. The communication connection in a specified section is confirmed first by receiving the turned loop back cell in the device that sends the loop back cell.
- Moreover, the meaning of this explanation is not understood. ｡｡
- Anyway, the part of "Send it back as it is" is a mistake, and "It rewrites in a specific value and send it back" answers correctly.
- The least significant bit of the loop back display field displays whether the loop back has already been executed by the pool algebra form. It is confirmed whether the loop back is executed by this field in the ATM layer. This field is coded to "00000001" in the source point. In the loop back point, it replaces it with "00 million".
The number of cell losses and the number etc. of mistakes of VP and VC can be confirmed on the receiving side according to information on the OAM cell for the continuity check.
These sentences are wrong.
- The number of cell losses and the number etc. of sign mistakes of VP and VC cannot be confirmed by using OAM cell information for the reception side continuity check.
- Anyway, it seems to be "It is not possible to judge on the receiving side. "
The continuity check function and the performance monitoring function start/are stopped by start/stop OAM cell. Which function start/is stopped is specified in peculiar to the function of the payload field.
These sentences are wrong.
- Which function start/is stopped is specified by the OAM function type of the payload.
- Continuity check or performance monitoring function or which is used is specified by "OAM function type".
Well, how about you?It is caught to the problem if it studies really neatly, and it doesn't remember surely if it is necessary to judge the correction from either that rewrites only ending of a words of sentences and sentences that can be taken. Because frequency of setting questions is considerably high, let's work hard and remember the OAM relation in the problem of the ATM. Then, around here today
2010/09/15
Problem of ATM adaptation layer
Well, please not only do ..problem of the ATM.. specialized subject and study the problem of the transmission exchange and the plant management hard the chief telecommunications engineer's of today study though it peels off ATM because it is an item of frequent occurrence.
Then, today's material is [kochira] ↓↓.
- ATM adaptation layer (AAL) type 5
The overhead when communicating compared with other AAL types is minimum because there are neither header nor trailers in cell splitting and assembly unpleasant sable (SAR) in AAL type 5.
These sentences are correct.
- The overhead when the AAL type 5= is communicated is minimum.
- There is AAL type neither the header nor 5= trailer (To SAR).
It differs from AAL type 3/4, and it mistakes and it detects it by cyclic check sign (CRC) in ten bits in each sequence number of the cell in AAL type 5.
These sentences are wrong.
- It mistakes only because of the CRC check of CPCS-PDU after the sequence number etc. of the cell are not used for the fault sensing, and the frame is assembled and it detects it.
- Each cell mistakes, it doesn't detect, each CPCS-PDU is mistaken because of the CRC check, and it detects it.
AAL type 5 can efficiently offer the voice and the image at a changeable speed in service class B of AAL to a high-ranking layer compared with AAL type 3.
These sentences are wrong.
- AAL type 5 is defined as an ATM adaptation layer to provide the voice at a changeable speed of service class B and the service of the image etc.
- ↑ Moreover, this explanation is unknown. ｡｡
- Because AAL type 5 is not connection OR connectionless "Class B" in class D because it is type VBR and "Class D", these sentences might be mistakes.
Well, how?The bytalk, I have the memory of the examination of the problem of this ATM in the document of the Cisco system well considerably and rolling it up. Because information is obtained on the site etc. where the qualification acquisition of the reference book of CCNP or Cisco was made a subject, I think it is good when looking over once when it is not good though it is not thought that the technical book of the ATM system is found to be an almost good. Then, around here today
Then, today's material is [kochira] ↓↓.
- ATM adaptation layer (AAL) type 5
The overhead when communicating compared with other AAL types is minimum because there are neither header nor trailers in cell splitting and assembly unpleasant sable (SAR) in AAL type 5.
These sentences are correct.
- The overhead when the AAL type 5= is communicated is minimum.
- There is AAL type neither the header nor 5= trailer (To SAR).
It differs from AAL type 3/4, and it mistakes and it detects it by cyclic check sign (CRC) in ten bits in each sequence number of the cell in AAL type 5.
These sentences are wrong.
- It mistakes only because of the CRC check of CPCS-PDU after the sequence number etc. of the cell are not used for the fault sensing, and the frame is assembled and it detects it.
- Each cell mistakes, it doesn't detect, each CPCS-PDU is mistaken because of the CRC check, and it detects it.
AAL type 5 can efficiently offer the voice and the image at a changeable speed in service class B of AAL to a high-ranking layer compared with AAL type 3.
These sentences are wrong.
- AAL type 5 is defined as an ATM adaptation layer to provide the voice at a changeable speed of service class B and the service of the image etc.
- ↑ Moreover, this explanation is unknown. ｡｡
- Because AAL type 5 is not connection OR connectionless "Class B" in class D because it is type VBR and "Class D", these sentences might be mistakes.
Well, how?The bytalk, I have the memory of the examination of the problem of this ATM in the document of the Cisco system well considerably and rolling it up. Because information is obtained on the site etc. where the qualification acquisition of the reference book of CCNP or Cisco was made a subject, I think it is good when looking over once when it is not good though it is not thought that the technical book of the ATM system is found to be an almost good. Then, around here today
2010/09/07
It is an outline of the ATM.
Well, I think that I do the problem of the ATM today. "Outline of the ATM" and the part that is only announcing and should suppressed by studying the ATM are published though it is thought that it only has to be able to read easily because this problem is "Fill-in-the-blank question". It first has in mind and it puts around here when not good at problem of the ATM. Then, today's material is [kochira] ↓↓.
- Outline of ATM
The cell used by the ATM is composed of 【53 bytes 】 that adds the header that contains routing information etc. by user information on the voice, the image, and data, etc.
- The ATM cell is composed of 【53 bytes 】 adding the header to user information.
In each cell header of the ATM, 【VCI】 that identifies a virtual channel as a connection identifier necessary to send it to the address until sending it and a virtual passing are identified. There is VPI, and the cell is turned to the address based on this information and the ATM switch is forwarded. At this time, to appear on the market, to seem to select [sen], and to advance, the ATM switch is said by the cell 【 self routing switch 】 about the address.
- 【VCI】 = virtual channel is identified.
- VPI = virtual passing is identified.
- 【 self routing switch 】 = seems to select the output line of the address by the cell and to advance.
There is a method of assuming a virtual channel to be to be remain set for a long term by the method and the contract, etc. to set to the setting method of a virtual channel only to communicate, and to liberate a virtual channel with the end of the communication. The virtual channel set by a latter method is called 【PVC】.
- Method of setting only SVC = to communicate, and liberating virtual channel with end of communication
- 【PVC】 Method of assuming virtual channel to be to be remain set for a long term by = contract etc.
Sleep. Outline really ?Because the part of the deficit becomes a really basic part to understand the ATM by right sentences, it neatly has in mind and it puts it. Coco is a liver of the ATM It was sentences explained almost bringing the ATM together. Then, because the outline was published a little more a little while ago, the problem of the ATM cell is done this time. Then, the following material is [kochira] ↓↓.
- Kind of ATM cell
To have continuously to spread the ATM cell over the payload of the SDH frame when the ATM cell is forwarded on the SDH network, an empty cell is inserted and forwarded between cells with effective information.
These sentences are correct.
- Because the payload is not integral multiples compared with 53 bytes of the size of the cell of the ATM, the last ATM cell on the frame might be accommodated across the following frame though the mapping is done by the payload of a virtual container of SDH as for the cell style to which the speed adjustment is done.
- An empty cell is inserted to put the speed of the ATM cell (speed of the valid cell) together at the transmission speed of SDH and the speed of the cell style adjusts.
- The ATM cell fully packs the package, inserts "Empty cell" in the opening part, and is doing the carrier of trailer (SDH) to SDH without the space. (padding)
- [Shitete], address VPI of the specialized form, and VCI become special like any one's neatly understanding "I am an empty cell" because it is not good this empty cell, too.
It is said by the ATM cell that doesn't contain the mistake in the header the valid cell excluding an empty cell.
These sentences are correct.
- The cell is . because it is errorless in the header excluding an empty cell (real cell) ..effective... ｡｡
It is said by the ATM cell to which the mistake is detected in the header, and it is corrected the invalid cell excluding an empty cell.
These sentences are wrong.
- This cell is up to . because it enacted the cell mistake ..effective.. though it might have been found to mistake it to the header excluding an empty cell (real cell). ｡｡･･･ It is a Japanese problem. ｡｡
When the cell mistake received in the error correction mode is detected, it mistakes it, and if the number of bits is one bit, it corrects, and if it is two bits or more, the cell is annulled.
These sentences are correct.
- I think that it is "FEC" that has come out before. Being able to do the error correction : only by one bit (annulment any more it) though FEC is possible the error detection and correction.
The difficulty so much doesn't write, and have it in mind, please often reading though "Oh…" seems to become because it fully packed the character in a narrow table for a moment. It often reads because the part that is the most basic the first half of today and this problem in the latter half understand the ATM. Then, around here today
- Outline of ATM
The cell used by the ATM is composed of 【53 bytes 】 that adds the header that contains routing information etc. by user information on the voice, the image, and data, etc.
- The ATM cell is composed of 【53 bytes 】 adding the header to user information.
In each cell header of the ATM, 【VCI】 that identifies a virtual channel as a connection identifier necessary to send it to the address until sending it and a virtual passing are identified. There is VPI, and the cell is turned to the address based on this information and the ATM switch is forwarded. At this time, to appear on the market, to seem to select [sen], and to advance, the ATM switch is said by the cell 【 self routing switch 】 about the address.
- 【VCI】 = virtual channel is identified.
- VPI = virtual passing is identified.
- 【 self routing switch 】 = seems to select the output line of the address by the cell and to advance.
There is a method of assuming a virtual channel to be to be remain set for a long term by the method and the contract, etc. to set to the setting method of a virtual channel only to communicate, and to liberate a virtual channel with the end of the communication. The virtual channel set by a latter method is called 【PVC】.
- Method of setting only SVC = to communicate, and liberating virtual channel with end of communication
- 【PVC】 Method of assuming virtual channel to be to be remain set for a long term by = contract etc.
Sleep. Outline really ?Because the part of the deficit becomes a really basic part to understand the ATM by right sentences, it neatly has in mind and it puts it. Coco is a liver of the ATM It was sentences explained almost bringing the ATM together. Then, because the outline was published a little more a little while ago, the problem of the ATM cell is done this time. Then, the following material is [kochira] ↓↓.
- Kind of ATM cell
To have continuously to spread the ATM cell over the payload of the SDH frame when the ATM cell is forwarded on the SDH network, an empty cell is inserted and forwarded between cells with effective information.
These sentences are correct.
- Because the payload is not integral multiples compared with 53 bytes of the size of the cell of the ATM, the last ATM cell on the frame might be accommodated across the following frame though the mapping is done by the payload of a virtual container of SDH as for the cell style to which the speed adjustment is done.
- An empty cell is inserted to put the speed of the ATM cell (speed of the valid cell) together at the transmission speed of SDH and the speed of the cell style adjusts.
- The ATM cell fully packs the package, inserts "Empty cell" in the opening part, and is doing the carrier of trailer (SDH) to SDH without the space. (padding)
- [Shitete], address VPI of the specialized form, and VCI become special like any one's neatly understanding "I am an empty cell" because it is not good this empty cell, too.
It is said by the ATM cell that doesn't contain the mistake in the header the valid cell excluding an empty cell.
These sentences are correct.
- The cell is . because it is errorless in the header excluding an empty cell (real cell) ..effective... ｡｡
It is said by the ATM cell to which the mistake is detected in the header, and it is corrected the invalid cell excluding an empty cell.
These sentences are wrong.
- This cell is up to . because it enacted the cell mistake ..effective.. though it might have been found to mistake it to the header excluding an empty cell (real cell). ｡｡･･･ It is a Japanese problem. ｡｡
When the cell mistake received in the error correction mode is detected, it mistakes it, and if the number of bits is one bit, it corrects, and if it is two bits or more, the cell is annulled.
These sentences are correct.
- I think that it is "FEC" that has come out before. Being able to do the error correction : only by one bit (annulment any more it) though FEC is possible the error detection and correction.
The difficulty so much doesn't write, and have it in mind, please often reading though "Oh…" seems to become because it fully packed the character in a narrow table for a moment. It often reads because the part that is the most basic the first half of today and this problem in the latter half understand the ATM. Then, around here today
2010/09/02
Today's topic is an ATM.
Well, chief telecommunications engineer's examination measures are done today. The problem related to the ATM thinks the subject of the transmission exchange and the plant management for you should make efforts and to finally exist because it is set questions at excellent frequency this time though it is a problem of a special field that tentatively handles a lot by this blog though it is a problem related to the ATM. Then, today's material is [kochira] ↓↓.
- ATM layer service
CBR is service that provides PCR(Perk Cell Rate), and guarantees CTD(Cell Transfer Delay), CDV(Cell Delay Variation), and the cell loss ratio.
These sentences are correct.
- CBR (Constant Bit Rate: constant bit rate): PCR (peak cell rate) is provided, and it is suitable for forwarding service and circuit switching services that guarantee CTD (cell transfer delay) and CDV and the cell loss ratio.
It doesn't make amends for the cell loss ratio though VBR is service to which SCR(Sustainable Cell Rate) and MBS(Maximum Burst Size) besides PCR are provided, and an image forwarding and an accumulative voice/data communication that uses the changeable speed sign assume it.
These sentences are wrong. - VBR (Variable Bit Rate: changeable speed service): SCR (average cell rate) besides PCR (peak cell rate) and MBS (maximum burst-length) are provided, and there are two categories of nrt-VBR for rt-VBR and the accumulation communication for serve real-time communication to which an image forwarding and an accumulative voice/data communication that uses the changeable speed sign are assumed and the cell loss ratio are guaranteed. - "The cell loss is secured. " though there are rough sentences.
It is a file transfer and service that is appropriate for the application of the transmission of the non-real-time data of E-mail etc. though not warranted the quality basically by UBR.
These sentences are correct.
- UBR (Unspecified Bit Rate): The file transfer and it serves that is appropriate for the application of the transmission of the non-real-time data of E-mail etc. though it doesn't warrant the quality basically.
ABR is to be adjusted the speed to install between MCR and PCR after MCR(Minimum Cell Rate) is secured by using RM cell (Resource Management Cell) to convenient service for the user who wants to use the bandwidth of becoming empty as much as possible.
These sentences are correct.
- From to install between MCR and PCR after MCR is guaranteed by using the transmission speed and RM (resource management) cell of the band that can be used, the speed is adjusted ABR (Available Bit Rate: bit rate that can be used): to convenient service for the user who wants to use the bandwidth of becoming empty as much as possible it.
How? It is confused and it divides, and refer the font color of the becoming it part in "Red", please the point the frequent occurrence of the term that looks like though it is a problem of the ATM (asynchronous transfer mode) though instigating it. An easy-to-use a little more in case of preserve it in the text editor or Excel duck because this blog is not thought to be terrible the table because right and left width of the article is narrow and to see easily. Then, around here today.
- ATM layer service
CBR is service that provides PCR(Perk Cell Rate), and guarantees CTD(Cell Transfer Delay), CDV(Cell Delay Variation), and the cell loss ratio.
These sentences are correct.
- CBR (Constant Bit Rate: constant bit rate): PCR (peak cell rate) is provided, and it is suitable for forwarding service and circuit switching services that guarantee CTD (cell transfer delay) and CDV and the cell loss ratio.
It doesn't make amends for the cell loss ratio though VBR is service to which SCR(Sustainable Cell Rate) and MBS(Maximum Burst Size) besides PCR are provided, and an image forwarding and an accumulative voice/data communication that uses the changeable speed sign assume it.
These sentences are wrong. - VBR (Variable Bit Rate: changeable speed service): SCR (average cell rate) besides PCR (peak cell rate) and MBS (maximum burst-length) are provided, and there are two categories of nrt-VBR for rt-VBR and the accumulation communication for serve real-time communication to which an image forwarding and an accumulative voice/data communication that uses the changeable speed sign are assumed and the cell loss ratio are guaranteed. - "The cell loss is secured. " though there are rough sentences.
It is a file transfer and service that is appropriate for the application of the transmission of the non-real-time data of E-mail etc. though not warranted the quality basically by UBR.
These sentences are correct.
- UBR (Unspecified Bit Rate): The file transfer and it serves that is appropriate for the application of the transmission of the non-real-time data of E-mail etc. though it doesn't warrant the quality basically.
ABR is to be adjusted the speed to install between MCR and PCR after MCR(Minimum Cell Rate) is secured by using RM cell (Resource Management Cell) to convenient service for the user who wants to use the bandwidth of becoming empty as much as possible.
These sentences are correct.
- From to install between MCR and PCR after MCR is guaranteed by using the transmission speed and RM (resource management) cell of the band that can be used, the speed is adjusted ABR (Available Bit Rate: bit rate that can be used): to convenient service for the user who wants to use the bandwidth of becoming empty as much as possible it.
How? It is confused and it divides, and refer the font color of the becoming it part in "Red", please the point the frequent occurrence of the term that looks like though it is a problem of the ATM (asynchronous transfer mode) though instigating it. An easy-to-use a little more in case of preserve it in the text editor or Excel duck because this blog is not thought to be terrible the table because right and left width of the article is narrow and to see easily. Then, around here today.
2010/08/26
It is a transmission exchange.
Well Well, let's study the chief telecommunications engineer today. the chief telecommunications engineer "" doesn't touch the railway track so much here by saying by the transmission exchange. ｡｡In handling chiefly by this blog, it is a problem for "Special subject exchange and transmission" and the problem of "Transmission exchange and plant management" is most. My having studied before becomes and because transmission was an exchange, that becomes a main by all means though it is thought that the topic of the data communication or the electric power is occasionally included. "How many years of the problem on earth are stocked?" increases the number of problems each day even to me when becoming accustomed to the management of this blog a little more though doesn't understand well because there is an excellent volume. Then, today's material is [kore] ↓.
ATM network and STM network
On the STM network, the speed menu offered to the user can offer a lot of speed menus in the ATM network though is generally limited 64Kbit/s and 1.5Mbit/s, etc.
These sentences are correct.
- The speed menu offered to STM network = user is generally limited to 64Kbit/s and 1.5Mbit/s, etc.
- A speed menu a lot of ATM network = can be offered.
Because the communication resource is occupied in the ATM network only when it is necessary, the burst data between networks can be efficiently transmitted compared with the STM network.
These sentences are correct.
- Data that occupies the communication resource only when it is ATM network = necessary and is the burst can be efficiently transmitted.
It is necessary to decide a physical multiplex position beforehand between sending and receiving as well as the STM network to identify the address in the ATM network according to cell header information.
These sentences are wrong.
- In the ATM, data is exchanged by the unit of all of the 53 bytes in length that are called a cell. The data part is 48 bytes among cells, and five bytes become header information. In this header, there are "Virtual passing identifier" that shows the address and "Virtual channel identifier", and the ATM network is a mechanism that data is delivered based on this information. Therefore, a physical multiplex position need not be decided between sending and receiving. ..-.. well, [itte] [toko] is mistaken need not ..→.. should the decision physical multiplex position.
Well, how do it say that it will require or about the current time in the time of which I took an examination as for the topic of the ATM though the rate of setting questions was high?But..transmission..world..provide..ATM..limit..by all means..such..problem..head..provide..work..remember.Then, around here today.
ATM network and STM network
On the STM network, the speed menu offered to the user can offer a lot of speed menus in the ATM network though is generally limited 64Kbit/s and 1.5Mbit/s, etc.
These sentences are correct.
- The speed menu offered to STM network = user is generally limited to 64Kbit/s and 1.5Mbit/s, etc.
- A speed menu a lot of ATM network = can be offered.
Because the communication resource is occupied in the ATM network only when it is necessary, the burst data between networks can be efficiently transmitted compared with the STM network.
These sentences are correct.
- Data that occupies the communication resource only when it is ATM network = necessary and is the burst can be efficiently transmitted.
It is necessary to decide a physical multiplex position beforehand between sending and receiving as well as the STM network to identify the address in the ATM network according to cell header information.
These sentences are wrong.
- In the ATM, data is exchanged by the unit of all of the 53 bytes in length that are called a cell. The data part is 48 bytes among cells, and five bytes become header information. In this header, there are "Virtual passing identifier" that shows the address and "Virtual channel identifier", and the ATM network is a mechanism that data is delivered based on this information. Therefore, a physical multiplex position need not be decided between sending and receiving. ..-.. well, [itte] [toko] is mistaken need not ..→.. should the decision physical multiplex position.
Well, how do it say that it will require or about the current time in the time of which I took an examination as for the topic of the ATM though the rate of setting questions was high?But..transmission..world..provide..ATM..limit..by all means..such..problem..head..provide..work..remember.Then, around here today.
2010/08/25
There is no reference book of the chief telecommunications engineer goodness ･･･.
If an almost useful reference book doesn't exist but even exists, chief telecommunications engineer's examination grind is easily useless ･･･ It is high in it. As the study method, it is a question in the past and [tteitte]. Giving it a butcher's when it asks and the word doesn't know in [no] is derived in the past is the one even of the problem of a considerably new technology that comes to be able to be answered when it depends, [ka] [samon] is digested, and it becomes accustomed to the atmosphere of the problem as the desire that the stance is the best. Well, today's material is ↓↓ *ATM.
As for synchronous transfer mode (STM), the multiplexed signal is periodically arranged. Therefore, because 【 time slot 】 is occupied by the signal when information not periodic is multiple transmitted, it is not efficient.
Because the time slot is decided at the cycle, inefficiency [nanona]. synchronous transfer mode ** STM = ..correct.. these sentences
It is said packet forwarding mode (PTM) is a method to divide information into the packet of 【 variable-length 】, and to do the protocol translation and the control of the mistake sending again in each packet, and it is unsuitable for the high-speed communication.
These sentences divide packet of ..correctness.. * forwarding mode = variable-length into the block.
To supplement these faults, information is transmitted by the cell of 【 fixed length 】 including connection destination information etc. in asynchronous transfer mode (ATM). Moreover, 【 hardware 】 can be processed because periodicity is not restricted when it is multiple because there is no frame cycle like the synchronous multiplex, many kinds of rate information can be multiplexed, and complex protocol processing is not done, and the achievement of speed-up is easy.
These sentences are correct. - It divides into the cell of ATM = fixed length (53 bytes).
Today's material was an ATM. ATM..say..automatic teller machine..sleep..asynchronous transfer mode..automatic teller machine..by the way..this..blog..explanation..every time..table..publish..this..table..left side..past..ask..excerpt..right side..the..sentence..correction..memorize..point..write..perhaps..well..today..table..as an example of..take..sentence..correct..examination..answer..correct.By the way, it asks and [ha] is done neatly by the problem collection in the past because the publishing order is published at random really capriciously. Then, around here ･･･ today
As for synchronous transfer mode (STM), the multiplexed signal is periodically arranged. Therefore, because 【 time slot 】 is occupied by the signal when information not periodic is multiple transmitted, it is not efficient.
Because the time slot is decided at the cycle, inefficiency [nanona]. synchronous transfer mode ** STM = ..correct.. these sentences
It is said packet forwarding mode (PTM) is a method to divide information into the packet of 【 variable-length 】, and to do the protocol translation and the control of the mistake sending again in each packet, and it is unsuitable for the high-speed communication.
These sentences divide packet of ..correctness.. * forwarding mode = variable-length into the block.
To supplement these faults, information is transmitted by the cell of 【 fixed length 】 including connection destination information etc. in asynchronous transfer mode (ATM). Moreover, 【 hardware 】 can be processed because periodicity is not restricted when it is multiple because there is no frame cycle like the synchronous multiplex, many kinds of rate information can be multiplexed, and complex protocol processing is not done, and the achievement of speed-up is easy.
These sentences are correct. - It divides into the cell of ATM = fixed length (53 bytes).
Today's material was an ATM. ATM..say..automatic teller machine..sleep..asynchronous transfer mode..automatic teller machine..by the way..this..blog..explanation..every time..table..publish..this..table..left side..past..ask..excerpt..right side..the..sentence..correction..memorize..point..write..perhaps..well..today..table..as an example of..take..sentence..correct..examination..answer..correct.By the way, it asks and [ha] is done neatly by the problem collection in the past because the publishing order is published at random really capriciously. Then, around here ･･･ today
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