The Multi Link ports (ML)

Terminology
Goal
Configuration of the ML ports
Statistics of the ML ports
SNMP traps generated for the ML ports


Terminology top

P-LINK
It stands for "Permanent link" and defines a permanent connection toward the remote device.
It also defines a kind of "logical" interface in the CPX that several drivers can emulate.
S-LINK
It stands for "Switched link" and defines a switched connection toward the remote device. A switched connection is established only upon request. It also defines the kind of "logical" interface offered in the CPX by EIR and Q931 drivers.
Link-check
It is a ML/ML procedure used to detect end-to-end link (or emulated p-link) real functioning, regardless of the lower protocol layers states.
It consists of periodical "link-check frames" exchange.
Bandwidth-on-Demand (uses Dial-on-Demand, Short-Hold-mode and True link backup. see MLM)
It is a feature that allows to open a new S-LINK channel when ML detects that the current throughput is too high for the current bandwidth. To detect this situation, ML has several parameters that indicate when a new channel must be open. A similar rule is used also when there is the possibility to close an S-LINK channel because of no more needed.

Goal top

Multi-Link (ML) basic concepts.

The ML driver is a very versatile driver. It is used as an intermediate layer to offer switched services for ISDN B-Channels to drivers and protocols that can support only permanent connections. It provides many extra functions like Bandwidth-on-Demand.

ML driver is the "gate" to:

Within CPX the ML appears to upper drivers as a single P-LINK port while it is able to use several lower ports of P-LINK and S-LINK types.

Configuration of the ML ports top

The Multi-Link port is referred in the Abilis CPX by the "ML" abbreviation, it has all the parameters described in the following section.

The layout of the ML port parameters changes considerably according to the used P-Link and S-Link port types.

Here are some examples of the ML port parameters.

ML default .

[18:42:32] ABILIS_CPX: D P PO:ML

ML over EIR.

PO:521 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500
       ------------------------------------------------------------------------
       SLINK:200      Chan:0                    CHAN-LIMIT:0
                      CGI:*                     SGI:*
                      CDI:*                     SDI:*
       CDOMAXCONN:2   CGO:#                     SGO:#
       CDONRTY:5      CDO:#                     SDO:#
       ------------------------------------------------------------------------
                         *** NO PLINKs CONFIGURED ***

ML over EIR.

PO:521 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500
       ------------------------------------------------------------------------
       SLINK:200      Chan:0                    CHAN-LIMIT:0
                      CGI:*                     SGI:*
                      CDI:*                     SDI:*
       CDOMAXCONN:2   CGO:#                     SGO:#
       CDONRTY:5      CDO:#                     SDO:#
       ------------------------------------------------------------------------
                         *** NO PLINKs CONFIGURED ***

ML over SYNC.

PO:523 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500
       ------------------------------------------------------------------------
       SLINK:NONE
       ------------------------------------------------------------------------
       Pl:1   ST:RUNNING   LOWPO:1     SPEED:64000

ML over FRAME-RELAY.

PO:524 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500
       ------------------------------------------------------------------------
       SLINK:NONE
       ------------------------------------------------------------------------
       Pl:1   ST:RUNNING   LOWPO:102   SPEED:64000    DLCI:NONE   
              CIR:0        BC:0        BE:0           SC:4         CC:YES

ML over FRAME-RELAY and EIR.

PO:528 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3   
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30  
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10   
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500 
       ------------------------------------------------------------------------
       SLINK:200      Chan:0                    CHAN-LIMIT:0   
                      CGI:*                     SGI:*    
                      CDI:*                     SDI:*    
       CDOMAXCONN:2   CGO:#                     SGO:#    
       CDONRTY:5      CDO:#                     SDO:#    
       ------------------------------------------------------------------------
       Pl:1   ST:RUNNING   LOWPO:102   SPEED:64000    DLCI:NONE   
              CIR:0        BC:0        BE:0           SC:4         CC:YES   

ML over EIR.

PO:529 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500
       ------------------------------------------------------------------------
       SLINK:200      Chan:0                    CHAN-LIMIT:0
                      CGI:*                     SGI:*
                      CDI:*                     SDI:*
       CDOMAXCONN:2   CGO:#                     SGO:#
       CDONRTY:5      CDO:#                     SDO:#
       ------------------------------------------------------------------------
                         *** NO PLINKs CONFIGURED ***

ML over NO LINKS.

PO:530 ------------------------------------------------------------------------
ML     LOG:DS        CRYPT:NO        CRKEY:DFT      T1:1000  T3:3000   N2:3
       ROLE:MASTER   MAXBW:2400      MINDATABW:0             DDT:60    VDT:30
       NORM-TH:50    FAST-TH:75      NORM-TIME:60   FAST-TIME:10
       Drx-pool:30   DRX-TOUT:3000   Vrx-pool:10    Vtx-pool:10   VTX-TOUT:500
       ------------------------------------------------------------------------
       SLINK:NONE
       ------------------------------------------------------------------------
                         *** NO PLINKs CONFIGURED ***

By the previous example, it is possible to underline that:

All the changes made on the ML port parameters can be immediately activated through the initialization command INIT PO: (this property is underlined by uppercase characters in their name), however it has to be noted that a possible active connection on the S-Link channel is closed with 80 90 80 8A code. The ML port will immediately be ready for a new communication, without affecting the upper level driver.

Warning! ML has another feature that allows the complete restart of the port, the command R PO: which allows ML to reload ALL the parameters in configuration, including those that otherwise would need a system restart.
As a result, LINK resources that were added or removed will be respectively activated or definitly deleted, limits on maximum SLINK channels changed to reflect the new values, and also buffers sizes updated.
All these operation are carried out without affecting the upper level driver, which will be "unaware" of the ML restart, unless the new configuration contains a mistake that prevent the communication.

Warning!Following the restart command R PO: all the active connections on the S-Link channel are closed with 80 90 80 8A code, however ML is immediately available for new connections.

Info Parameters that can be activated with the R PO: command can be identified by the initial character in UPPERCASE and subsequent ones in LOWERCASE, e.g. Vrx-pool:, Chan:, ...

The changes made on the parameter LOG: are immediately active.

Details of the ML ports parameters


LOG: Events logging activation and generation of alarm signals
DS NO, D, S, A, L, T, ALL, +E

Usually this parameter makes possible to activate/deactivate logging functionalities of meaningful events of the port as well as the detection and signalling of alarms in case of critical events.

The following table shows the available options and the related functionalities usable by the parameter:

Option Meaning
D Recording of the driver state changes and/or the meaningful events in Debug Log
S Recording of the driver state changes and/or the meaningful events in the System Log
A Periodic detection of possible alarms. The detected alarms can be displayed the command ALARM VIEW or by the analogous command available on the UTILITY of the LCD display on the front panel
L On alarm detection, acoustic signal generation plus a message on the LCD display. This function depends on activation of alarms detection by the "A" option
T Generation by the Agent SNMP of Abilis CPX of SNMP traps corresponding to any change of the driver state and/or occurring of meaningful events

Beside the already described options the following values are also allowed:

Option Meaning
NO It means that all the logging functionalities, alarms detection and generation, above mentioned, are disabled.
ALL It means that all the logging functionalities, alarms detection and generation, above mentioned, are enabled.
+E This option added to one or more of the previous ones, extends its (their) set of meaningful events.
The value "ALL+E" activates all the options and extends the set of meaningful events.
The value "NO+E" is meaningless so it is ignored.

Options can be combined together.

Some examples:

By using the characters "+" and "-" as prefix of one or more options is possible to add or delete one or more functionalities without setting from the scratch the value of the parameters.

Some examples:

warning! The changes made on this parameter are immediately activated, without the need of initialization commands.


CRYPT: Enable and select cryptography
NO NO, DATA, VOICE, ALL

It enables and selects the cryptography to be applied on the frames passing through the port. Cryptography can be selectively applied to the different traffic types (VOICE and DATA):

Value Meaning
NO No cryptography is applied.
DATA Cryptography is applied only on DATA traffic type.
VOICE Cryptography is applied only on VOICE traffic type.
ALL Cryptography is always in use, whatever is the traffic data type.

CRKEY: Index of the key used for the cryptography
DFT DFT, 1 - 63

It selects the key to be used for cryptography operations.

Users can choose either the default key supplied by the system ("CRKEY:DFT"), or one of the keys defined in the cryptography keys table, in which case the numeric value (from 1 to 63) corresponding to the desired CRKEY has to be specified.

If the configured value refers to a missing CRKEY it will be shown inside square brackets, e.g. "CRKEY:[5]" means that the key number 5 is not present in the table.

If the parameter CRYPT: is set to NO, the value of "CRKEY:" is useless.


T1: Link-Check "probes" Timeout
1000 200-3000 (in milliseconds)

Maximum time to wait for a Link-Check "probe" acknowledge. If this time elapses without receiving the acknowledge the "probe" is immediately repeated, as a result "not acknowldged probes" are repeated every T1 milliseconds.


T3: Time interval between transmission of Link-Check "probes" when link is functioning
3000 600-9000 (in milliseconds)

This is the time interval between a correctly sent and acknowledged Link-Check "probe" and the next one to send while the link is regularly working (e.g. P-LINK state is READY). It has relationships with the parameter T1: and it has to satisfy the simple rule: T3 > T1 * 2.


N2: Maximum number of Link-Check "probes" retransmission
3 1 - 99

Sets the maximum number of Link-Check "probes" retransmission.

If this counter runs over, it means "N2" Link-Check "probes" have been sent without receiving any acknowledge, the P-Link or S-Link channel is declared out of service.

In the case it occurs on the P-Link channel, the communication will be activated on the S-Link channel, providing that it is properly configured.

In the case it occurs with the S-Link channel, the connection is closed with the code 80 90 80 8B; if it happens three times consecutively the port will be placed in the "STOPPED2" state, without being able to receive or make further calls.

To recover from the error it is necessary to execute the INIT PO: command.

If alarm detection was enabled, i.e. if LOG is set with the "A" option, it is also possible to recover from the error with the ALARM RESET command or using the analogous menu available on the LCD display of the front panel.

If the communication cannot go on any longer either on P-Link or S-Link, the upper level driver will be advised of the error and point out a "Level 1 Down".


ROLE: ML role
MASTER MASTER, SLAVE

This parameter indicates the role of the ML. When ML is configured as a MASTER, it has the complete control on all its lower links. It can decide to open or close them following its throughput rules. When ML is configured al SLAVE, it has a reduced set of controls. It can only open one single S-LINK only when strictly needed.

Warning!

MLs connected together cannot have the same role. In this case will be both automatically set to SLAVE.


MAXBW: Maximum bandwidth
2400 2400-99999999 (bps)

It is the maximum bandwidth allowed to accross over ML links. If the bandwidth that is going on ML connection is higher that maximum, ML will no open other S-LINK.


MINDATABW: Minimum bandwidth for DATA
0 0-99999999 (bps)

it is the minumum bandwidth that must be left for DATA.

Warning!

If MINDATABW is not set to 0, one link will be always open: will be opened a PLINK if at least one PLINK is configured and CONNECTED. Will be opened a S-LINK if no P-LINKS are configured or set to DOWN and at least there is a S-LINK present.


DDT: Time-out for extra Slinks shutdown for DATA
60 from 10 up to 1000 (in seconds)

DDT is the time that ML uses to analyze the DATA throughput on the LINKs. When ML considers that for DDT seconds current throughput could be managed also without one SLINK, it starts the DATA procedure to close the SLINK.

Warning! ML closes the SLINK only when both DATA and VOICE procedures to close SLINK were started.

When the SLINK is closed, ML waits at least other DDT seconds before checking again for SLINK closure. This procedure is used by ML if at least one SLINK is open. See Bandwidth On Demand documentation for more deatails about rules used for DATA stream to detect when SLINK can be closed by ML.


VDT: Time-out for extra Slinks shutdown for VOICE
30 from 10 up to 1000 (in seconds)

VDT is the time that ML uses to analyze the VOICE throughput on the LINKs. When ML considers that for VDT seconds current throughput could be managed also without one SLINK, it starts the VOICE procedure to close the SLINK.

Warning! ML closes the SLINK only when both DATA and VOICE procedures to close SLINK were started.

When the SLINK is closed, ML waits at least other VDT seconds before checking again for SLINK closure. This procedure is used by ML if at least one SLINK is open. See Bandwidth On Demand documentation for more deatails about rules used for VOICE stream to detect when SLINK can be closed by ML.


NORM-TH: Threshold for NORMAL opening of additional SLinks
50 0 - 100 (%)

This parameter indicates the threshold for opening an S-LINK after a certain amount of time. When the current throughput is higher than normal threshold, ML analises this situation for NORM-TIME: seconds. If after this period, threshold percentage is still higher than NORM-TH, then a new SLINK will be opened (if present and ready to be opened).

Warning!

The percentage is not calculated using the total bandwidth of the currently opened links: it is calculated using the total bandwidth of the currently opened links LESS the REAL bandwidth used by voice frames.


FAST-TH: Threshold for FAST opening of additional SLinks
75 0 - 100 (%)

It follows the same rules of NORM-TH:. The difference is that the period of time to wait before opening the link is indicated by FAST-TIME:


NORM-TIME: Time-out for NORMAL opening of additional SLinks
60 10-1000 (seconds)

This is the period that ML has to analyze before opening an additional S-LINK channel when current data throughput is higher than NORM-TH:


FAST-TIME: Time-out for FAST opening of additional SLinks
10 5-100 (seconds)

This is the period that ML has to analyze before opening an additional S-LINK channel when current data throughput is higher than FAST-TH:


Drx-pool: Rx pool size for DATA frame
30 1-255 (KBytes)

This is the amount of DATA frames (in Kbytes) that ML can handle when receiving from remote ML.


DRX-TOUT: Rx time out for DATA frame
3000 50-10000 (msec)

This parameter indicate when DATA frames hold in ML pool (DRX-POOL:) must be considered in time-out and then directly forwarded to higher layer. This situation could happen when previous frame was not yet arrived and ML was waiting for it before submitting next datagram to higher layer.


Vrx-pool: Rx pool size for VOICE frame
10 1-255 (KBytes)

This is the amount of VOICE frames (in Kbytes) that ML can handle when receiving from remote ML.


Vtx-pool: Tx pool size for VOICE frame
10 1-255 (KBytes)

This is the amount of VOICE frames (in Kbytes) that ML can handle when sending them remote ML. This is needed because could happen that several voice frames cannot be sent to a specific LINK because of, for example, this link went down. In this case, ML cannot stop the voice frame stream because other voice frames probably were sent on other working LINKs, so, only VOICE that cannot be temporally sent are stored into this pool.


VTX-TOUT: Tx time out for VOICE frame
500 100-3000 (msec)

This time-out is used when several voice frames are present in VOICE pool (see VTX-POOL:) and they were hold more than VTX-TOUT. This method is to avoid that once VOICE frames can be sent (because for example another link were opened), they are not too old for the remote side.


SLINK: Identifier of the Abilis CPX port of S-Link level
200 1 - 999, NONE

It defines the S-Link port of lower level, it can be of EIR or Q931 type.

If the S-Link port is not desired, the parameter has to be set to "NONE".


Chan: Number of S-Link configured
0 0-32

This parameter indicates how many SLINK channels are managed by ML.

Warning!

This doesn't mean that can be always opened CHAN SLINKs. Also CHAN-LIMIT: must be considered.


CHAN-LIMIT: Maximum number of openend S-Link
0 0-CHAN:

Specify the maximum number of SLINK channels that can be opened by ML.


CDOMAXCONN: Output called address maximum number of connections
2 0-32

This parameter indicates how many SLINK channels can be opened using CDO number.

Warning!

If ML needs to open a new SLINK (due to throughput, see NORM-TH: and FAST-TH:) and the number of SLINK opened using CDO: is the same of CDOMAXCONN, then no more SLINK will be opened, even if present in configuration.


CDONRTY: Maximum number of call repetitions
5 0 - 65534, NOMAX

It specifies the maximum number of call repetitions for the S-Link channel when the connection cannot be established. Once attempts are exhausted the S-Link chennel is place in STOPPED1 state.

Warning! If the channel is established BUT the "link-check protocol" detects link-check failure for three times consecutively the port is placed in STOPPED2 state regardless the NRTY counter.

Value Meaning
0 Outgoing calls are disabled.
1-65534 Calls are repeated as many times as the value.
NOMAX Calls are repeated indefinitely.

CGI: Calling address of the incoming call
* from 1 up to 20 numerical characters [0- 9], *

It sets up the calling address, that the incoming call must contain.

The character "*" means "any number".


SGI: Calling sub-address of the incoming call
* from 1 up to 20 alphanumerical [0- 9, a - z, A- Z], *

It sets up the calling sub-address, that the incoming call must contain.

The character "*" means "any character".


CDI: Called address of the incoming call
* from 1 up to 20 numerical characters [0- 9], *

It sets up the called address, that the incoming call must contain.

The character "*" means "any number".


SDI: Called sub-address of the incoming call
* from 1 up to 20 alphanumerical [0- 9, a - z, A- Z], *

It sets up the called sub-address, that the incoming call must contain.

The character "*" means "any character".


CGO: Calling address of the outgoing call
# from 1 up to 20 numerical characters [0- 9], #

It sets up the calling number of the outgoing call.

The character "#" means "no number", if it is set, the outgoing call will not contain the calling address.


SGO: Calling sub-address of the outgoing call
# from 1 up to 6 alphanumerical [0- 9, a - z, A- Z], #

It sets up the calling sub-address of the outgoing call.

The character "#" means "no number", if it is set, the outgoing call will not contain the calling sub-address.


CDO: Called address of the outgoing call
# from 1 up to 20 numerical characters [0- 9], #

It sets up the called number of the outgoing call.

The character "#" means "no number", if it is set, the outgoing call will not contain the called address.


SDO: Called sub-address of the outgoing call
# from 1 up to 6 alphanumerical [0- 9, a - z, A- Z], #

It sets up the called sub-address of the outgoing call.

The character "#" means "no number", if it is set, the outgoing call will not contain the called sub-address.


Pl: P-Link port identifier
1 1-32

It identifies the PLINK configured in ML list. Can be considered as an index and it is used to access PLINK parameters.


ST: P-Link port state
DELETED NEW, DELETED, RUNNING

Status of the PLINK configuration.

NEW: PLINK is added in ML configuration, but it is not yet operative (ML needs to be restarted).

DELETED: PLINK is removed from ML configuration, but it is yet present into ML resources, even if no more used (ML needs to be restarted to completely remove it from memory).

RUNNING: PLINK is present in configuration and working. This is the only status where ML can send/receive datagrams on this P-LINK.


LOWPO: Identifier of the Abilis CPX port of P-Link level
NONE 1 - 999, NONE

It defines the P-Link port of the lower level, which can only be SYNC, FR, ISDN, PLINKE or EIR type.

If no P-Link port is required, the value "NONE" must be set.


SPEED: Line speed
64000 (Kbit/sec)

This is the maximum bandwidth on the P-LINK. This field is very important because it is used when calculating throughput percentage (see NORM-TH: and FAST-TH:).


BCHAN: Identifier of the channel B to use (only if the P-Link is an ISDN port type)
B1 B1, B2

The parameter appears and can be modified only if the port referred by the parameter LOWPO: is an ISDN Basic Rate port type, i.e. the service provided by "only data" ISDN adaptors.

It defines the channel to be used on the lower level ISDN port.


DLCI: Identifier of the DLCI to use (only if the P-Link is a FR port type)
NONE 16-991, 1024-63487, 131072-8126463, NONE

The parameter appears and can be modified only if the PLINK referred is a FR port type.

It defines the identifier of the DLCI to use the lower lever FR port.

The value "NONE" means "no DLCI" and it disables the connection with the lower level FR port.

The validity of allowed values intervals for the DLCI identifier depends on the length of the header Frame-Relay in use:

Value Meaning
NO No cryptography is applied.
DATA Cryptography is applied only on DATA traffic type.
VOICE Cryptography is applied only on VOICE traffic type.
ALL Cryptography is always in use, whatever is the traffic data type.

CC: Activation of the congestion control
YES NO, YES

The parameter appears and can be modified only if the port referred by the parameter PL: is a FR port type.

It makes possible to apply or to not apply the throughput reduction as reaction to congestion notifications.

warning!Not obeying to congestion notification may cause severe malfunctioning, therefore we strongly reccommend to always use CC:YES. Ignoring congestion notification may be needed for some testing activities, certainly not during the regular work.


SC: Value of the constant "step count", used in congestion control (only if the P-Link is a FR port type)
4 1 - 50

The parameter appears and can be modified only if the port referred by the parameter PL: is a FR port type.

It sets how many consecutive frames with BECN=1 have to be received for reducing the throughput, according to the rule fixed by ANSI T1.618 annex A §2.1.1.

Value 4 suits the most frequent situations, however the right value can be evaluated by using the Calculator.


CIR: Value of "Committed Information Rate" (only if the P-Link is a FR port type)
0 0, 4800 - 2500000 in bit/sec

The parameter appears and can be modified only if the port referred by the parameter PL: is a FR port type.

It defines the value of "Committed Information Rate", i.e. the throughput the frame-relay network has to guarantee in normal working conditions. This throughput is measured in the time interval TC (Time Committed) given by the following formula: TC=BC/CIR.

The set up value must correspond to that one established by contract with the operator of the frame-relay network.


BC: Value of "Burst Committed" (only if the P-Link port is a FR port type)
0 0, 2400 - 5000000 in bits

The parameter appears and can be modified only if the port referred by the parameter PL: is a FR port type.

It defines the "Burst Committed", i.e. the number of bits the network can accept, during the time interval TC, to guarantee the CIR.

If the network is congested, it sends a signal (BECN or FECN) that require the user to progressively reduce his throughput to values smaller than CIR.

The set up value must correspond to that one established by contract with the operator of the frame-relay network.


BE: Value of "Burst Excess" (only if the P-Link is a FR port type)
0 0 - 5000000 in bits

The appears and can be modified only if the port referred by the parameter PL: is a FR port type.

It defines the "Burst Excess", i.e. the number of bits in excess that the network can manage, during the time interval TC, if there is availability of exceeding resources. The "exceeding throughput" is evaluated by using the following formula ThExcess=BE*TC.

When the network does not have resources in excess sends a signal (BECN or FECN) that engages the user to immediately limit the throughput to the value of the CIR.

The set up value must correspond to that one established by contract with the operator of the frame-relay network.


VSP-ID: Service identifier (only if the P-Link is a EIR port type)
NONE NONE, 1 - 32

This parameter indicates which Virtual Synchronous Port (VSP) of those defined in the TDM table the ML must use.

Statistics of the ML ports top



Example of how to check the state and statistics of ML ports by the command D S

[17:09:33] ABILIS_CPX: D S PO:521

PO:521 ------------------------------------------------------------------------
ML     STATE:DOWN  PLINKs:ALL-DOWN   CHANs:STOPPED1 ROLE-Cur/Conf:MASTER/MASTER
                   Max-BW:0          Cur-BW:0              N-DOWN:1
       - Data: ---------|-------INPUT-------|-------OUTPUT------|-Thresholds--|
              Avail-BW: |0                  |0                  |             |
       NORM-Throughput: |         0/  0/ 50 |         0/  0/ 50 |0            |
       FAST-Throughput: |         0/  0/ 75 |         0/  0/ 75 |0            |
       - Voice: ------------------------------------|---INPUT----|--OUTPUT----|
       CHANs:0          BW:0            Throughput: | 0          | 0          |
       ------------------------------------------------------------------------
       PL:1    ST:CONNECTED  DN1:0                     DN2:0
       ------------------------------------------------------------------------
       MAX-RTY:0           CUR-RTY:0           DDT:18     VDT:30
       -----------|---INPUT---|--OUTPUT---|-----------|---INPUT---|--OUTPUT---|
       FAIL-CALL  |          0|          0|SUCC-CALL  |          0|          0|
       TIME-CALL  |          0|          0|CUR-CALL   |          0|          0|
       ------------------------------------------------------------------------

[17:09:36] ABILIS_CPX: 

Example of how to check the extended statistics of ML ports by the command D SE

[17:10:47] ABILIS_CPX: d se po:521

PO:521 ------------------------------------------------------------------------
ML     --- Cleared 000:00:01:55 ago, on 03/04/2002 at 17:09:00 ----------------
       -----------|---INPUT---|--OUTPUT---|-----------|---INPUT---|--OUTPUT---|
       CHR        |          0|          0|FRM        |          0|          0|
       CHR-D      |          0|          0|FRM-D      |          0|          0|
       CHR-V      |          0|          0|FRM-V      |          0|          0|
       CHR-C      |          0|          0|FRM-C      |          0|          0|
       LOST-D     |          0|           |BAD-FRM    |          0|          0|
       LOST-V     |          0|          0|CRYPTO-ERR |          0|          0|
       D-TOUT     |          0|           |D-OUT-SEQ  |          0|           |
       D-MISSING  |          0|           |D-RESYNC   |          0|           |
       ------------------------------------------------------------------------
       -----------|---INPUT---|--OUTPUT---|-----------|---INPUT---|--OUTPUT---|
       FAIL-CALL  |          0|          0|SUCC-CALL  |          0|          0|
       TIME-CALL  |          0|          0|CUR-CALL   |          0|          0|
       ------------------------------------------------------------------------
       ------------------------------------------------------------------------
       PR CDO                  ST   SUCC-CALL  FAIL-CALL  TIME-CALL  CUR-CALL
       ------------------------------------------------------------------------
       1  12345                GOOD 3          2          10         500       

[17:10:55] ABILIS_CPX:

The information "Cleared DDD:HH:MM:SS ago, at DD/MM/YYYY HH:MM:SS", referred by the extended statistics, shows both the elapsed time from the last reset of the statistics (by the format "days:hours:minutes:seconds") and date/time of its execution (by the format "day/month/year" and "hours:minutes:seconds").

Details of the ML state fields and statistics


STATE: Current state of the ML driver
DOWN, READY, ERR

It shoes the current state of the ML port driver.

Driver States Meaning Values shown in:
System Log Debug Log Display LCD
ML DOWN Both PLINKs and CHANs states are DOWN     DN
READY Port is active     RD
ERR Software error, contact Abilis assistance.     NA


PLINKs: Status of PLINKs.
ALL-DOWN, ALL_READY, SOME-READY, ERR

Indicates the global PLINK status. The information is the result of all the PLINKs configured in ML.

Value Meaning
ALL-DOWN All the PLINKs in ML are in DOWN state.
ALL-READY All the PLINKs in ML are in DOWN state.
SOME-READY At least one PLINK in ML is in READY state, the remaining PLINKs are DOWN.
ERR Software error, contact Abilis assistance.

CHANs: Status of SLINKs.
STOPPED1, READY, ERR

Indicates the status of SLINK channels.

Value Meaning
STOPPED1 ML cannot make other outgoing calls on SLINK due to errors.
READY ML can attempt to open a SLINK.
ERR Software error, contact Abilis assistance.

ROLE: Current/configured ML role.
SLAVE - MASTER

Indicates the current ML ROLE and the value in the ROLE set in configuration. This information is useful because when both MLs are set as MASTER, they are automatically forced to SLAVE. In this way will be detected soon that a configuration error occurs.


MAX-BW: Max bandwidth.
0-99999999 (bps)

Indicates the maximum bandwidth that ML could reach if ALL its LINKs were open. In order to have more bandwidth will be necessary to increase the number of LINKS.


CUR-BW: Current bandwidth.
0-99999999 (bps)

Indicates the current bandwidth available in ML. This information is calculated making a sum of the bandwith of all the LINKS currently open.


N-DOWN: Counter of DOWN states.
0 - 4.294.967.295

This statistic indicates how many times the ML state went DOWN. The DOWN state is reached when ALL PLINKs configured are DOWN and when SLINKs cannot be opened.


Avail-BW: Available DATA bandwidth.
0 - 4.294.967.295

Indicates the available bandwidth for DATA throughput. It is calculated making the difference between the Cur-BW and the sum of the theoretical throughput of all the VOICE frames (BW:).


NORM-Throuhput: Normal throughput informations.

This table row indicates several things. 3 columns are present: the first and the second column contain the information about current data throughput and thresholds percentage. The first field has the current throughput of DATA frames. Throughput is calculated making an average of the DATA throughput on the last NORM-TIME seconds and the available bandwidth (Avail-BW). The second field is the percentage of the DATA throughput previously described. This percentage is calculated on the available data bandwidth. The third field contains the configured normal threshold NORM-TH. In the third column there is the threshold information: it indicates how many time the percentage calculated on data throughput was greated than normal threshold configured NORM-TH.


FAST-Throuhput: Fast throughput informations.

This row contains similar informations to NORM-Throuhput. The difference is that throughput is calculated on last FAST-TM seconds, and the percentage threshold is FAST-TH.


CHANs: Number of voice channels currently opened.
0 - 239

Indicates the number of voice channels that are currently opened by upper layer. ML detects the number of opened channels analizing the informations present in voice frames.


BW: Theoretical throughput of voice frames.
0 - 4.294.967.295

A distinction must be done about theoretical and real throughput. To calculate real throughput, ML analyses every second the amount of BITs sent/received on VOICE frames. About theoretical throughput, it is the result of the sum of the bandwidth declared by upper layer when opening VOICE channel.


Throughput: Real VOICE frames throughput
0 - 4.294.967.295

To calculate real throughput, ML analyses every second the amount of BITs sent/received on VOICE frames. The result will be a value expressed in bits per seconds..


PL: PLink indicator.
1 - 32

It indicates for which PLINK the informations on this row are referred to.


ST: Status of the PLINK.
CONNECTED

Indicates the current status of the PLINK.


DN1: DOWN1 counter.
0 - 4.294.967.295

Indicates how many times this PLINK went in DOWN1 state.


DN2: DOWN2 counter.
0 - 4.294.967.295

Indicates how many times this PLINK went in DOWN2 state.


MAX-RTY: MAX SLINK retries.
0 - RTY

It indicates the RTY parameter set in ML configuration. In this way will be made a fast comparison with current retries (CUR-RTY).


CUR-RTY: Current SLINK retries.
0 - RTY

It indicates the current number of retries attempted by ML in order to open a SLINK.


DDT: DATA Disconnection time.
0 - DDT

This parameter indicates the time elapsed when ML has started to analyse throughput of DATA frames. For more informations see DDT:


VDT: VOICE Disconnection time.
0 - VDT

This parameter indicates the time elapsed when ML has started to analyse throughput of VOICE channels. For more informations see VDT:


FAIL-CALL: Unsuccessfull SLINK calls.
0 - 4.294.967.295

Indicates the number of times the ML tried to open a SLINK but it cannot.


SUCC-CALL: Successfull SLINK calls.
0 - 4.294.967.295

Indicates the number of times that ML opened a SLINK successfully.


TIME-CALL: SLINK connection counter.
0 - 4.294.967.295 (seconds)

Indicates the sum of seconds that every SLINK was connected from REBOOT or from ML RESTART (or when statistics were cleared). This statistic make a distinction about incoming and outgoing calls and takes care also of the SLINK currently connected.


CUR-CALL: Current SLINK open connection counter.
0 - 4.294.967.295 (seconds)

Indicates the sum of seconds of the current opened SLINKs.


CHR: Number of received/sent characters
0 - 4.294.967.295

The counter CHR (INPUT) is incremented every time a frame is received. The counter CHR (OUTPUT) is incremented every time a frame is sent.


FRM: Number of received/sent frame
0 - 4.294.967.295

The counter FRM (INPUT) is incremented every time a frame is received. The counter FRM (OUTPUT) is incremented every time a frame is sent.


CHR-D: Number of received/sent DATA characters
0 - 4.294.967.295

The counter CHR-D (INPUT) is incremented every time a DATA frame is received. The counter CHR-D (OUTPUT) is incremented every time a DATA frame is sent.


CHR-C: Number of received/sent Link-Check characters
0 - 4.294.967.295

The counter CHR-C (INPUT) is incremented every time a Link-Check frame is received. The counter CHR-C (OUTPUT) is incremented every time a Link-Check frame is sent.


CHR-V: Number of received/sent VOICE characters
0 - 4.294.967.295

The counter CHR-V (INPUT) is incremented every time a VOICE frame is received. The counter CHR-V (OUTPUT) is incremented every time a VOICE frame is sent.


FRM-D: Number of received/sent DATA frames
0 - 4.294.967.295

The counter FRM-D (INPUT) is incremented every time a DATA frame is received. The counter FRM-D (OUTPUT) is incremented every time a DATA frame is sent.


FRM-C: Number of received/sent Link-Check frames
0 - 4.294.967.295

The counter FRM-C (INPUT) is incremented every time a Link-Check frame is received. The counter FRM-C (OUTPUT) is incremented every time a Link-Check frame is sent.


FRM-V: Number of received/sent VOICE frames
0 - 4.294.967.295

The counter FRM-V (INPUT) is incremented every time a VOICE frame is received. The counter FRM-V (OUTPUT) is incremented every time a VOICE frame is sent.


LOST-D: Number of DATA frames sent and lost
0 - 4.294.967.295

The counter LONG-D (INPUT) is incremented every time a DATA frame is discarded because there are no available receiving buffers.


BAD-FRM: Number of frames received in a bad format
0 - 4.294.967.295

Number of frames received in a bad format.


LOST-V: Number of VOICE frames sent and lost.
0 - 4.294.967.295

The counter LONG-V (INPUT) is incremented every time a VOICE frame is discarded because there are no available receiving buffers.


CRYPTO-ERR: Cipher error.
0 - 4.294.967.295

Input: Number of received frames discarded due to bad ciphering or missing cipher key.

Output: Number of sending frames discarded due to missing cipher key.


D-TOUT: DATA frames time-out
0 - 4.294.967.295

Is used to indicate how many times the receiver DATA buffer gone in time-out due to missing DATA frame.


D-OUT-SEQ: Out of sequence DATA frames.
0 - 4.294.967.295

Number of out-of-sequence DATA frames received.


D-MISSING: Missing data frames.
0 - 4.294.967.295

Number of datagram lost due to re-sequence of DATA frames.


D-RESYNC: Resync request.
0 - 4.294.967.295

Number of resincronisation requests.


PR: CDO number priority list identifier.
0 - 4.294.967.295

Indicates the priority of this CDO number. Lower is the number, higher is the priority.


CDO: Called address of the outgoing call.
from 1 up to 20 numerical characters [0- 9], #

Indicates the called number of the outgoing call.


ST: Status of CDO number.
STOP, GOOD, ERR

Indicate the status of CDO number. If GOOD, this number can be used for outgoing calls. If STOP, this number will no more used for calling until an INIT or a RESTART of ML port.

Value Meaning
STOP ML will use no more this number for calling until an INIT or a RESTART.
READY This CDO number can be used by ML for outgoing calls.
ERR Software error, contact Abilis assistance.

SUCC-CALL: Successfull SLINK calls.
0 - 4.294.967.295

Indicates the number of times that ML opened a SLINK successfully.


FAIL-CALL: Unsuccessfull SLINK calls.
0 - 4.294.967.295

Indicates the number of times the ML tried to open a SLINK with this CDO number, but it cannot.


TIME-CALL: SLINK connection counter.
0 - 4.294.967.295 (seconds)

Indicates the sum of seconds that this CDO number used by a SLINK establish a connection from REBOOT or from ML RESTART (or when statistics were cleared). This statistic indicates only outgoing calls and takes care also of the SLINK currently connected.


CUR-CALL: Current SLINK open connection counter.
0 - 4.294.967.295 (seconds)

Indicates the sum of seconds of the current opened SLINKs by CDO number.

SNMP traps generated for the ML port top

The SNMP Agent of Abilis CPX is able to generate traps owing to meaningful state changes pertinent either to P-Link or S-Link channels of the ML.

SNMP traps generated for global state changes pertinent to all P-Link channels of the ML port

The traps listed below are generated when at least the "T" options are set in the LOG: parameter, corresponding to the basic SNMP traps generation functionality provided for ML ports.

Trap own code Mnemonic of the trap SNMP variables reported in the trap Description
53 cxTrapMlAllPLinksDown cxPortIndex,
cxPortType,
cxMlDiagGlobalPLinkState,
cxMlDiagGlobalSLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that all P-Links of a ML port currently running are in DOWN state.
54 cxTrapMlAllPLinksReady cxPortIndex,
cxPortType,
cxMlDiagGlobalPLinkState,
cxMlDiagGlobalSLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that all P-Links of a ML port currently running are in READY state.
55 cxTrapMlSomePLinksReady cxPortIndex,
cxPortType,
cxMlDiagGlobalPLinkState,
cxMlDiagGlobalSLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that some P-Links of a ML port currently running are in READY state.

SNMP traps generated for global state changes pertinent to all S-Link channels of the ML port

The traps listed below are generated when at least the "T" options are set in the LOG: parameter, corresponding to the basic SNMP traps generation functionality provided for ML ports.

Trap own code Mnemonic of the trap SNMP variables reported in the trap Description
56 cxTrapMlSLinksStopped1 cxPortIndex,
cxPortType,
cxMlDiagGlobalPLinkState,
cxMlDiagGlobalSLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that all S-Links of a ML port currently running are in STOPPED1 state.
57 cxTrapMlSLinksReady cxPortIndex,
cxPortType,
cxMlDiagGlobalPLinkState,
cxMlDiagGlobalSLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that all S-Links of a ML port currently running are in READY state.

SNMP traps generated for a single P-Link channel of the ML port

The traps listed below are generated only when the "T+E" options are set in the LOG: parameter, i.e. it is required an extension of the basic SNMP traps generation functionality.

Trap own code Mnemonic of the trap SNMP variables reported in the trap Description
58 cxTrapMlPLinkDown cxPortIndex,
cxPortType,
cxMlDiagPLinkIndex,
cxMlDiagPLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that a single P-Link of a ML port currently running is in DOWN state.
59 cxTrapMlPLinkUp cxPortIndex,
cxPortType,
cxMlDiagPLinkIndex,
cxMlDiagPLinkState,
sysUpTime
The SNMP Agent of the Abilis CPX generates this kind of trap every time it recognizes that a single P-Link of a ML port currently running is in UP state.

Details of the SNMP variables reported in the ML traps


cxPortIndex FR port, which the SNMP trap refers to
0 - 999

This variable stores the CPX port number, which the SNMP trap refers to.


cxPortType Type and description of the ML port, which the trap refers to
type - description

This variable reports either the port type which the trap refers to (in this case it will be ML) and the description that eventually the user can give to the CPX port.


cxMlDiagGlobalPLinkState Global P-Link channels state
all-down(0), all-ready(1), some-ready(2)

This variable reports the current value of the global P-Link channels state.

SNMP variable value Corresponding Global P-Link channels state
all-down(0)ALL-DOWN
all-ready(1)ALL-READY
some-ready(2)SOME-READY

cxMlDiagGlobalSLinkState Global S-Link channels state
stopped1(0), ready(1)

This variable reports the current value of the global S-Link channels state.

SNMP variable value Corresponding Global S-Link channels state
stopped1(0)STOPPED1
ready(1)READY

cxMlDiagPLinkIndex P-Link channel indentifier
1 - 32

This variable reports the P-Link channel identifier for which the trap is generated.


cxMlDiagPLinkState P-Link channel state
none(0), link-np(1), link-err(2), down1(3), down2(4), ready(5), listening(6), called(7), calling(8), connected(9), clearing(10), cleared(11), undefined(12)

This variable reports the current state of the P-Link channel, which the trap refers to. The following table shows the relationship between the state values, referred by the SNMP variables, and the states carried out by executing the command D S.

SNMP variable value Corresponding P-Link channel state
none(0)NONE
link-np(1)LINK-NP
link-err(2)LINK-ERR
down1(3)DOWN1
down2(4)DOWN2
ready(5)READY
listening(6)LISTENING
called(7)CALLED
calling(8)CALLING
connected(9)CONNECTED,
CONN-TO,
CONN-FROM
clearing(10)CLEARING
cleared(11)CLEARED
undefined(12)UNDEFINED

sysUpTime Elapsed time since the system has been started by the occurred event
0 - 4.294.967.295 or "ddd:hh:mm:ss"

This variable reports the elapsed time (in cents of second) since the occurred event, which has generated the SNMP, started the system. This value is usually shown by using the format days:hours:minutes:seconds.

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