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W-lvetica--,`H1`D4PkC"S^11>bbu"::Dg1:11bbbbbbbbbb11gggbuuuk1Xubuukuuuk111Rb:bbXbb1bb''X'bbbb:X1bXXXX;.;g:=::m:::mmmmm::::::mm:k1mubububububXubububub11111111bbbbbbbbbuXubbkbuXmmmmumububXXXXbububububbmbbbbbb:k:k::=kmmX:uXb'b:b:b:b'bmbbbb:::uXuXuXuXk:k:k:mbbbmbuXkXkXKQmmmm^b:kbbbbmbA@mmbmmbmmmmmmm:b:mmmbbmmmmmmmmmmmmXXmmmmmmmmmmmmmmmmmmcm`m`mm`m:mmmmmm}}}mjjmmmmmmmmmmmmmmm0mm}mmmmmmmmmmmmmmmmmmmmmmm}Mmmmmmmmmmmmmjmmmtmmmmmmmmm`'mmm`mmjmlWmmmmmmmmmmmmmmmmmmmW`mmmmjmMQMS PS Jet Plus /800 II QPJPII.PRSPl`D4PkCg2W_qD#|xHelveticaCourier@,`H1`D4PkCmQrrr r  @C2 KG@,`H1`D4PkCmQrrr r  @C;,>>> >  @C ` X` hp x (#%'H   x|@  3'3'Standard5'5'StandardC6QMS $=R- 13.1HRecommendation G.960 < DIGITAL SECTION FOR ISDN BASIC RATE ACCESS 1.HHGeneralxH 1.1HHScopexH  `  HThis Recommendation describes the characteristics of a digital section for the ISDN basic rate access between the user network interface (at T reference point, defined in Recommendation I.411 and the local exchange (at V1reference point defined in Q.512) supporting the recommended channel structure 2B+D and the required additional functions. HIn this Recommendation and unless otherwise indicated, the term TE is used to indicate terminating layer 1 aspects of TE1, TA and NT2 functional groups. HWhen the term TE indicates terminating layer 1 aspects of TE1, then according to Figure 2/I.411, the S and T reference points coincide. HThe terminology used in this Recommendation is very specific and not contained in the relevant terminology Recommendations. Therefore Annex B to this Recommendation provides terms and definitions used in this Recommendation. 1.2HHConfiguration%H HFigure 1/G.960 shows the boundaries of the digital section in relation to the digital system definition.  h Note Digital transmission system refers to either a line system using metallic pairs, optical fibres or radio systems. 8"Figure 1/G.960 Note The T and V reference points are defined in Recommendations I.411 and Q.512. 1.3HApplication HThe basic access digital section may be applied as given in Figure2/G.960 for:  h HH©X direct access to the local exchange (V1reference point);   `  ,Ԍ `  HH©X access via a basic access multiplex equipment (V4interface) to the local exchange;$  `   ` ( HH©X access via a basic access concentrator (V2interface) to the local exchange;ư"  (`   `  2.HModelling and relationship between the digital section and the ET HThe general model shown in Figure 3/G.960 depicts the whole ISDN customer access layer 1 and adjacent entities and provides the basis to describe the functions performed by the digital section and those perfomed by TE, ET and system management and how various functions are grouped. In particular, according to this model the activation/deactivation procedures and maintenance functions specified in this Recommendation are not confined to functions perfomed by the digital section but include functions associated with ET layer 1.  H HThis model includes primitive procedures between ET layer 1, ET layer, 2 and system management:  H HHi)X  I.430 to I.440/I.441 interactions between ET layer 1 and ET layer 2, and ET layer 1 and system management based on PH and MPH primitives, respectively, as defined in Recommendation I.430. These interactions are for the support of functions specified in Recommendations I.440 and I.441;$  `   `  HHii)X  interactions between ET layer 1 and system management for the support of functions associated with the digital section, based on MPH primitives.(#  `   `  HThe primitive procedures within TE comply with the specification according to Recommendation I.430.   HThis model does not constrain layer 1 arrangements between LT and NT1, (it is also applicable to remote access as shown in Figure2/G.960), or the digital transmission system technology. 3.HFunctions HFigure 4/G.960 shows the functions which have to be supported by the basic access digital section.  ,Ԍ  h Note 1 These functions are conveyed by the CV1 channel across the V1 reference point. Note 2 This function is optional. Note 3 The activation and deactivation functions are concerned with the operation of the digital section and the usernetwork interface. However, for consistency with Recommendations I.430, they are described as separate functions. 8"FIGURE 4/G.960 8) 8Functions of the digital sectionă B Channel HThis function provides, for each direction of transmission, two independent 64 kbit/s channels for use as B Channels (as defined in Recommendation I.412). D Channel HThis function provides, for each direction of transmission, one DChannel at a bit rate of 16 kbit/s, (as defined in Recommendation I.412). Bit timing HThis function provides bit (signal element) timing to enable the receiving equipment to recover information from the aggregate bit stream. Regarding the V1 reference point, the bit timing function is used for both transmit and receive data. Octet timing HThis function provides 8 kHz octet timing for the B Channels. Activation Activation from ET HThis function places all the functions of the digital section into a normal operating mode and supports the activation of the interface at the T reference point according to Recommendation I.430. This takes into account: HH©X power down mode;p&  h`  HH©X initial power up;x HH©X a failure condition.x  ` X HThe procedures and exchange of information are described in  5 of this , Recommendation. HAn activation should be possible to a state which allows maintenance actions to be performed in the digital section even when there is no customer equipment connected to the T reference point. HIn the case of a basic access digital section making use of a digital transmission system for a metallic line one additional mode of operation may be applied for activation/deactivation, which is to activate/deactivate the digital section only. This is optional. Request for activation from TE HThis function supports activation of the digital section and of the interface at the T reference point according to Recommendation I.430. HThese functions are conveyed by the CV1 channel (see  7). Deactivation HThis function is specified in order to permit the interface at the T reference point and the digital section to be placed in a low power consumption mode. The procedures and exchange of informationn are described in  5 of this Recommendation. HDeactivation should be initiated only by the exchange (ET). HThis function is conveyed by the CV1 channel (see  7). Power feeding HThis function provides for remote power feeding of NT1 and optionally the TE via the user network interface in accordance with Recommendation I.430,  9. Operation and maintenance HThis function supports required actions and information for operating and maintaining the digital section controlled by the ET as defined in Recommendation I.603. HFour categories of functions have been identified: HH©X commands regarding LT, regenerator, or NT1;ƀ%  X`  HH©X information from LT, regenerator, or NT1;x HH©X indications of fault conditions;x HH©X control of digital section power feeding.x HThese functions are conveyed by the CV1 channel (see  7). 4.HNetwork performance 4.1HAvailibility HThe definition of availability is given in Annex A of Recommendation G.821. The availability objective of the digital section should be consistent with the availability requirement for the hypothetical reference digital section as given in Recommendations G.801 and I.Qnp. 4.2HSignal transfer delay ,Ԍ  ` 8 HSignal transfer delay is specified for B Channels and is defined as absolute signal delay between T and V1 reference points for each direction  8 of transmission. The value is for further study. The relevant Recommendatons have to be taken into account (e.g. signal transmission delay when the signal represents speech must be taken into account as one component of the endtoend delay requirement of Recommendation G.114). 4.3HError performance HError performance must be consistent with the requirements given in Recommendation G.821. 4.4HJitter 4.4.1 HOutput/input jitter at T reference point HThe requirements are defined in  8 of Recommendation I.430. 4.4.2HJitter at V1 reference point. HThe input jitter limits are for further study.  ` HH@    x|@  5'5'StandardC6QMS $=R6'6'StandardC6QMS $=R-   6.HOperation and maintenance 6.1HGeneral  `  HThis paragraph describes the operation and maintenance functions for the digital section of the ISDN basic rate access. For the time being only functions for a digital transmission system for a metallic line are defined. HOperation functions related to activation/deactivation procedure are specified in paragraph 5. HFurther assumptions regarding the system management are given in Annex A. HThe maintenance functions recommended in I.603 provide the capability to maintain the digital section to the level of Network Performance given in  4 of this Recommendation. HIt must be possible to test and maintain the digital section in accordance with Recommendation I.603 regardless of the customer equipment. HThe main features are: Ha)  control of maintenance and test support facilities; Hb)  monitoring of the functional elements to provide operating and   HHX performance information and fault condition indications;X   `  Hc)  maintenance communication facility. 6.2 HControl facilities 6.2.1HLoopbacks 6.2.1.1HLoopback implementation  `  HThe location and characteristics of loopbacks are defined in Recommendation I.603. 6.2.1.2HLoopback procedure HThe loopbacks are controlled by ET system management. HA normal call activation request cannot override a request for loopback 1, 1a or 2. 1Ԍ  X HThe procedure for loopback operation always starts from the deactivated state of the digital section. HOne possible sequence is: Ha)  ET generates an operation command for the required loopback; Hb)  ET receives MPHAI; Hc)  ET performs the test; Hd)  ET generates a release command; He)  ET receives MPHDI. 6.2.2HAuxiliary equipment line switchover HThe function provides control of switchovers across the VI reference point: Ha)  to switch the line from the LT to a line measurement device; Hb)  to switch the line from the normal LT to a standby LT; Hc)  to switch the LT to test NT1 located in the local exchange. HThis function is optional. The function definition, control options and procedures are for further study. 6.2.3HControl of functions in the NT1 HThis function allows control of specific functions within the NT1 and is for further study. HAn example of such a function is as follows: H e.g., control of switching between normal and restricted power at the user network interface.ƀ% 6.2.4HInformation request HThis function allows the ET to request from the LT, regenerator and NT1 specific status reports. 6.2.5HPower switch on/off to the line HThis function allows switching of the power to the line, and may be automatically applied upon reception of a power feed failure indication. 6.2.6HContinuity test HThe continuity test is described in Recommendation I.603. HThe continuity test is controlled by the ET and is initiated by MPHAR. System management decides when the test is passed (i.e. on reception of MPHDSAI or MPHAI). When the system management receives MPHEI (expiry T1) the test is considered to be failed. See also Annex A to this Recommendation. 6.3HMonitoring 6.3.1HFunctions HThe following operational conditions are monitored throughout the section: Ha)  the defect conditions; Hb)  the power feed arrangements; Hc)  transmission performance. 1Ԍ 6.3.2HImplementation aspects HMonitoring capabilities must be provided in the digital section (see Recommendation I.603). The handling and processing of the information is implementation dependant. For example: Ha)  the use of registers/counters in functional groups, the use of explicit commands and responses to establish status reports; Hb)  the transfer of information to the exchange, either when a defect condition occurs or on a regular basis. This information is then processed by entities outside the digital section.ƀ% 6.3.3HAnomaly and defect conditions and consequent action 6.3.3.1HDefect conditions HThe following defect conditions are examples: Hi)  excessive error rate; Hii)  loss of incoming signal; Hiii)  loss of frame alignment; Hiv)  power feed failure. Note One example of an anomaly is a transmission error. 6.3.3.2HConsequent actions HFurther to the detection of a defect condition appropriate actions should be taken as specified in Table 5/G.960. HDefect indication information (FII) is automatically transmitted from the digital section to the ET. H@ p"TABLE 5/G.960 ( Defect conditions and consequent actionsă      EQUIPMENT  DEFECT  CONSEQUENT ACTIONS     CONDITIONS      FII  SIGNAL AT V1  SIGNAL AT T     LT EXCESSIVE ERROR RATE  YES  FFS  FFS     LOSS OF SIGNAL  YES  FE4  INFO5    LINE SIDE  LOSS OF FRAME  YES  FE4  INFO5           NT EXCESSIVE ERROR RATE  YES  FFS  FFS     LOSS OF SIGNAL  YES  NOT APPLICABLE  INFO5    LINE SIDE  LOSS OF FRAME  YES  NOT APPLICABLE  INFO5           NT AT T  LOSS OF SIGNAL  YES3  FE4  NOT APPLICABLE     LOSS OF FRAME  YES3  FE4  NOT APPLICABLE           NT  LOSS OF POWER  YES2  FFS  INFO O     pHP  Note 1 If processed in the digital section. Note 2 Depending on power feed arrangements, optional. Note 3 Optional. Note 4 This signal is defined in paragraph 5.  1ԌNote 5 Whether an existing INFO as defined in I.430 may be used is for further study. 6.3.4HError performance monitoring 6.3.4.1HGeneral HProvision has to be made in order to monitor the error performance of the digital section and to report on such performance. 6.3.4.2HError performance parameters HThe digital section must deliver to the ET the necessary information to allow it to evaluate the error performance parameters defined in Recommendation G.821. 6.3.5HStatus report functions HStatus report functions cover information which relate to the overall operation and performance of the digital section. The information may be transmitted either automatically or under request of ET. HListed below are descriptions of the status report functions: Hi)  Transmission errors H This information, derived in the digital section, allows the ET to HHX evaluate the transmission error performance;ƀ%  X`  Hii)  Loopback 1 statusx  `  HHX This information, sent from the LT, gives the status of X  HHX loopback 1;X   `  HHX Hiii)  Loopback 1A statusx  ` H HHX This information, sent from the regenerator, gives the status of loopback 1A;Ɛ$  H`  Hiv)  Loopback 2 status  `  H This information, sent from the NT1, gives the status ofX  HHX loopback 2;X   `  Hv)  User network interface power feed status  `  HHX This information indicates the status of the user network interface at T reference point power feed, e.g., normal or restricted power feed mode;H!  `  Hvi)  User network interface power feed fault  ` H HHX This information indicates a failure of the normal or restricted power source.Ɛ$  H`  HHX This function may be split into two reports.x HHX This information is reported on request of the ET;x Hvii)  User network interface power feed overload  `  H This information indicates that the power drawn from any source within the NT1 exceeds the maximum power that is available.$ H This information is reported on request of the ET; HHX HHviii)  Defect indication information$ 1Ԍ  8 HHX This information is transmitted automatically under conditions specified in 6.3.3.1.Ơ#  8` <TABLE 6/G.960 < <Status report functionsă <   <  FUNCTION  LOCATION  MANDATORY/OPTIONAL  < <  Transmission errors  LT  M  <   REG.  O  <   NT  O  <     <  Loopback 1 status (Note)  LT  M  <     <  Loopback 1A status (Note)  REG.  M  <     <  Loopback 2 status (Note)  NT1  M  <     <  T reference point power  NT1  O  <  feed status    <     <  T reference point power  NT1  0  <  feed fault    <     <  T reference point power  NT1  O  <  feed overload    <     <  FII  LT  M  <   REG.  M  <   NT  M  <    `  Note The information may be implicit (e.g., activation indication). 6.3.6HSystem dependent status report functions HThese status reports will be dependent upon the type of digital transmission system used and require further study.   HSome examples of a particular system are given in Table 7/G.960. TABLE 7/G.960 $ System dependent status report functionsă      FUNCTION  LOCATION   1 Ԍ  Line test relay state  LT    LT test relay state  LT    Remote power switch state  LT    Remote power feed  LT    Induced overvoltage on line  LT    Abnormal current condition  LT    Receive eye opening  LT     REG.     NT1    Echo cancellation coefficients  LT     REG.     NT1    Battery test  NT    7.HControl channel CV1   HThis control channel provides, for each direction of transmission, the capability to transfer the commands, status report information and FII. HAlthough described as a single channel, the control channel may be realized by a number of subchannels which may use different transport mechanisms (as appropriate to the functions). Even though some of the functions mentioned in  6 have optional status, the CV1 channel shall have the capability to convey all the control information to allow their implementation. $ANNEX B ' (to Recommendation G.960) ' Vocabulary of terms used in connection with ă Recommendations I.430, I.431, G.960 and G.961 (Will reproduce the text of Annex E to Recommendation I.430, see COM XVIIIR 61/AP IX146.)  1 Ԍ