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`EXHIBIT 2064 
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`Part 2 of 2 
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`ANSI X3.230-1 994 27 Segmentation and reassembly 27.1 Introduction 27.2.3 Subblock Segmentation and reassembly are the FC-2 func- tions provided to subdivide application data cor- responding to an Information Category to be transferred into Payloads, compute Relative Offset values, embed each Payload and the cor- responding Relative Offset value in an individual frame, transfer these frames over the link, and reassemble at the receiving end the application data of the Information Category as sent by the sending end. Application data mapping Mapping application data to Upper Level Proto- cols (ULPs) is outside the scope of FC-PH. ULPs maintain the status of application data trans- ferred. 27.2 Sending end -- -- . An upper level (a level above FC-2) at the ending end shall define a Relative Offset space for each Information Category for which Relative Offset usage is supported. An upper level speci- fies a block or a collection of subblocks to be transferred within a Sequence. -27.2.1 Relative Offset space The Relative Offset space shall start from zero, representing an upper level-defined origin, and extend to its highest value. Application data for an Information Category transferred may be mapped to all or portions of Relative Offset space. A subblock is an upper level construct which contains partial data for a single Information Cat- egory. A collection of subblocks is specified for a given Information Category to be transferred within a Sequence. The subblocks shall be specified, only if the Sequence Recipient sup- ports Random Relative Offset. An upper level shall specify an Initial Relative Offset for each subblock. The Initial Relative Offset value is allowed to be zero or non-zero. The Initial Rela- tive Offset values of subblocks of a given Infor- mation Category transmitted consecutively are allowed to be random. The collection of subblocks for a single Informa- tion Category is allowed to map to portions or all of Relative Offset space for the Information Cate- gory. 27.2.4 Sequence The blocks to be transferred within a single Sequence and the Information Category for each block shall be specified to FC-2 by an upper level. The collections of subblocks to be trans- ferred within a Sequence and the information Category for each subblock shall be specified to FC-2 by an upper level. 27.2.5 Relationship between Sequences The Relative Offset relationship between multiple Sequences of a given Information Category shall be specified by an upper level. This relationship is transparent to FC-2. 27.2.2 Block 27.3 FC-2 A block is an upper level construct of application data related to a single Information Category and transferred within a single Sequence. If Continuously Increasing Relative Offset is used, a block shall be specified. A block is allowed to map to all or part of Relative Offset space of the Information Category. An upper level shall specify an Initial Relative Offset (IROi) for each block. The Initial Relative Offset value is allowed to be zero or non-zero. Mechanisms FC-2 mechanisms to support this function are a) Relative Offset or SEQ_CNT b) Sequence c) F_CTL bit indicating the presence of Relative Offset in the parameter field (see 18.2) Relative Offset The Parameter field in the Frame-Header may be used to hold the value of Relative Offset which is the relative displacement of first byte of 244
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`II pLi (m + n)
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`ANSI X3.230-1994 Payload related to an upper level-defined origin for a given Information Category. Sequence Count (SEQ_CNT) If Relative Offset is not used for reassembly, the information Category shall be reassembled using the SEQCNT. The reassembly shall be performed by joining or concatenating the Pay- loads of the Data frames in the continuously increasing order of SEQ_CNTs starting from the SEQCNT of the first Data frame to that of the last Data frame of a given Sequence. For an Information Category i within a given Sequence, the reassembly is expressed as Application data, = PL, (m) II PL, (m + 1) II 000
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`where PL (m) represents Payload ‘. of a frame with SEQCNT m n is the total frame count within the Sequence m is the lowest SEQ_CNT (zero or non- zero) and m i- n is the highest SEQ_CNT. -- - - . - If the SEQ_CNT wraps to zero from hex FFFF 4. within a Sequence, the reassembly shall be con- tinued according to modulo 65536 arithmetic (i.e., SEQ_CNT = 0 follows SEQ_CNT = hex FFFF). 27.4 Login The following Common Service Parameters * related to segmentation and reassembly are interchanged during N-Port Login (see figure 61): a) Relative Offset by Information Category b) Continuously Increasing or Random Relative Offset Through the interchange of these Login parame- ters, the Sequence Recipient indicates its Rela- tive Offset requirements to the Sequence Initiator. The Sequence Recipient indicates Rel- ative Offset support or non-support for each Information Category. For the Relative Offset supported Information Categories, the Sequence Recipient collectively indicates Continuously Increasing or Random Relative Offset require- ment. The Sequence Initiator shall follow the Relative Offset requirements of the Sequence Recipient, for Information Categories supported and not supported. 27.5 Segmentation Segmentation summary referred to table 110. rules summary rules are listed and a) The Sequence Initiator shall be responsible for segmentation. The Sequence Initiator shall follow the Relative Offset requirements of the Sequence Recipient for Information Cat- egories. b) An upper level at the sending end shall specify to the sending FC-2 one or more blocks to be transferred as a Sequence, the Information Category for each block, an Rela- tive Offset space, and the Initial Relative Offset for each Information Category. The Initial Relative Offset value may be zero or non-zero. c) The Sequence Initiator shall use the specified Relative Offset space for each Information Category and transfer one or more blocks specified in a single Sequence. d) If the Sequence Recipient does not support Relative Offset for one or more Information Categories, the Sequence Initiator shall transmit each of these Information Categories as a contiguous block. The Sequence Initiator shall set the Relative Offset present bit in F_CTL to zero, indicating that the parameter field is not meaningful. e) If the Sequence Recipient supports Relative Offset for one or more Information Categories and has specified during Login this support as Continuously Increasing Relative Offset, the Sequence Initiator shall transmit each of these Information Categories with Continuously Increasing Relative Offset. 1) The Sequence Initiator shall set the Rela- tive Offset present F_CTL bit to one. 2) The Sequence Initiator shall use the Initial Relative Offset specified by the upper level for the Relative Offset ROi in the first frame of the block, namely, ROi(0) = Initial Relative Offset (IROi) for the Information Category i 3) The Sequence Initiator shall use for all other frames of the block, the Relative Offset computed as follows: RO,(n+l) = RO,(n) + Length of Payload,(n) where n is 2 0 (zero) and represents the consecutive frame count of frames for a 245
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`ANSI X3.230-1994 given Information Category within a single Sequence. 4) Above steps 1 through 3 shall be repeated for each block within the Sequence. f) If the Sequence Recipient supports Relative Offset for one or more information Categories and has specified during Login this support as Random Relative Offset, the Sequence Initi- ator is permitted to transmit each of these Information Categories with Random Relative Offset. 1) The Sequence Initiator shall set the Rela- tive Offset present F_CTL bit to one. 2) The Sequence initiator shall use the Initial Relative Offset specified by the upper level for the Relative Offset ROi in the first frame of the subblock, namely, ROi(0) = Initial Relative Offset (IROi) for the ‘e Information Category i 3) The Sequence Initiator shall use for all other frames of the subblock, the Relative Offset computed as follows: -- RO,(n+l) = RO,(n) + Length of -- . - Payload,(n) where n is I 0 (zero) and represents the consecutive frame count of frames for the subblock for a given Information Category within a single Sequence. 4) Above steps 1 through 3 shall be repeated for each subblock within the Sequence. -27.6 Reassembly rules summary Reassembly summary rules are listed and referred to table 110. a) The Sequence Recipient shall be responsible for reassembly of each Information Category received within the Sequence. The Sequence Recipient shall use Relative Offset or SEQ_CNT field, as specified, to perform the reassembly and make the blocks available to the receiving upper level as sent by the sending upper level. b) The Sequence Recipient shall reassemble each Information Category within its Relative Offset space specified by the sending upper level. c) If the Sequence Recipient has specified during Login non-support of Relative Offset for one or more Information Categories, the Sequence Recipient shall verify Relative Offset present F_CTL bit for zero value and reassemble each of these Information Catego- ries using SEQ_CNT. If this F_CTL bit is set to one for any of these Information Categories, the Sequence Recip- ient shall issue a P_RJT with a reason code of “Relative Offset not supported.” d) If the Sequence Recipient has indicated during Login Relative Offset support for one or more Information Categories and specified this support as Continuously Increasing Rela- tive Offset, the Sequence Recipient shall verify Relative Offset present F_CTL bit for one and assemble each of these Information Catego- ries using Relative Offset. If the Sequence Initiator lacks the Relative Offset capability and has set the bit to zero, the Sequence Recipient shall use SEQ_CNT for reassembly. e) If the Sequence Recipient has indicated during Login Relative Offset support for one or more Information Categories and specified this support as Random Relative Offset, the Sequence Recipient shall verify Relative Offset present F_CTL bit for one and assemble each of these Information Categories using Relative Offset. If the Sequence Initiator lacks the Relative Offset capability and has set the bit to zero, the Sequence Recipient shall use SEQCNT for reassembly. f) If the Sequence Recipient supports Contin- uously Increasing Relative Offset and detects random Relative Offsets, the Sequence Recip- ient shall issue P_RJT with the reason code of “Relative Offset out of bounds”. 246
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`ANSI X3.230-1994
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`Case Table 110 - Segmentation and reassembly rules summary Relative Offset support Sequence initiator action Sequence Recipient by Sequence Recipient (Segmentation) action (Reassembly) - Relative Offset shall - F_CTL Relative Offset present bit = 0 not be used (ignore - Parameter field not meaningful parameter field) - SEQ_CNT shall be 1 Not supported used - Issue P_RJT - F_CTL Relative Offset present bit = 1 - Parameter field = Relative Offset - Reason code = Relative Offset not supported - F_CTL Relative Offset present bit = 1 - Parameter field = Relative Offset - First frame of a block: RO,(O) = IRO, for the block specified Relative Offset Continuously - All other frames of the block: shall be used 2 Increasing Relative Offset RO,(n+l) = RO,(n) + Length of supported Payload,(n) - Ignore parameter - F_CTL Relative Offset present bit = 0 - Parameter field not meaningful field - SEQ_CNT shall be used - F_CTL Relative Offset present bit = 1 - Parameter field = Relative Offset - Initial Relative Offset for subblocks permitted to be random - First frame of a subblock: Relative Offset Random ROi(O) = IRO, for the subblock specified shall be used 3 Relative Offset - All other frames of the subblock: supported ROi(n+l) = ROi(n) + Length of Payloadi( n) - Ignore parameter - F_CTL Relative Offset present bit = 0 - Parameter field not meaningful field - SEC_CNT shall be used Note: If RO value in the Parameter field is out of bounds, the Sequence Recipient shall issue a P_RJT with a reason code of “Invalid Parameter field”. 247
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`ANSI X3.230-1994 28 Connection management The procedures for establishing and removing Class 1 Dedicated Connections are specified in this clause. See annex Q for application exam- ples for removing a Connection. 28.1 Introduction Class 1 Service is based on establishing a Dedi- cated Connection between a source N-Port and a destination N-Port. The Dedicated Connection guarantees that the full bandwidth of the Link is available to each N-Port. Establishing a Connection ‘. In order to establish a Class 1 Dedicated Con- nection, the source N-Port shall transmit a Data frame to a destination N-Port with an SOFcl delimiter. The Data field size of the connect- -- _ -- - - request frame is limited by the maximum buffer- . To-buffer Receive Data-Field size specified by 6e Common Service Parameters of the Fabric (or point-to-point N-Port) or by the maximum Receive Data-Field size specified by the destina- tion N-Port, whichever is smaller. The N-Port shall receive an R_RDY Primitive Signal to indicate that the connect-request frame *was received successfully and a buffer in the F-Port or N-Port is available. No additional frames shall be transmitted for the pending Con- nection until the ACK frame has been received. When the N-Port transmitting the connect- request receives an ACK (ACK_1 or ACK_N) with an SOFnl and with the appropriate S-ID and D-ID fields of the connect-request frame, a Dedi- cated Connection is established. NOTES 1 A Connection is established from the N-Port’s per- spective (Connection Initiator) at the time the N-Port receives the ACK frame. It has no relation to the method or timing by which the Fabric actually forms the Dedicated Connection. 2 It is recommended that a Fabric not introduce a phase discontinuity (see 5.3) while establishing a Class 1 Connection. No frame errors are introduced by such a discontinuity. When a Dedicated Connection is established: - Both N-Ports shall reinitialize their end-to-end Class 1 Credit to the Login values. - the N-Port initiating the connection shall be known as the Connection Initiator and the N-Port responding to the connect-request shall be known as the Connection Recipient. - the Connection Initiator may continue the initial Sequence, and - the Connection Recipient may initiate new Sequences with an SOFit delimiter when a Dedicated Connection is not unidirectional, as indicated by the setting of F_CTL bit 8 (see 28.5.3). Removing a Connection Removing a Dedicated Connection is accom- plished by either N-Port transmitting a frame ter- minated by an EOFdt or the transmission or reception of the Link Reset Primitive Sequence. Normally, removing a Dedicated Connection shall be negotiated between the two N-Ports involved. Negotiation is required in order to avoid breaking the Dedicated Connection while frames are still flowing between the N-Ports. In urgent situations which do not require the use of the Link Reset Primitive Sequence, an N-Port may request the immediate removal of a Dedi- cated Connection by transmitting the Remove Connection Basic Link Service frame. The ACK frame transmitted in response shall end with an EOFdt delimiter. The Fabric terminates a Dedicated Connection after an EOFdt or EOFdti passes through the F-Port in either direction. Any frames flowing in either direction at the time the Connection is removed may be corrupted. End-Connection (E-C) is the control bit in F_CTL which is used to perform the negotiation. Frame processing precedence There are a number of different fields within a frame which affect the processing for estab- lishing and removing Dedicated Connections. The general precedence hierarchy follows: a) Frame delimiters (SOFcl, EOFdl), b) R_CTL 248
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`- Data frame, or - Link_Controi frame. c) F_CTL - Unidirectional Connection, ingful (bit 8), - End-Sequence (bit 19), - other bits when meaningful when mean- (for example, if bit 19=1, check End-Connection, Chained-Sequence, and so forth) as in tables 38 and 39. 28.2 Applicability Connection management applies to Class 1 Service. An N-Port supporting Class 1 Service may also support Class 2 and _ Class 3. Depending on the options supported by the * Fabric, multiple class support by an N-Port may be complex. Because Class 1 involves Dedi- cated Connections, managing Class 1 usually overrides Class 2 or 3 management. FC-PH -specifies the allowable responses on a Class by -- Class basis. . - + NOTE - An N-Port engaged in Class 2 communication with another N-Port may experience Sequence time- outs if the other N-Port supports Class 1 and Class 2 without functioning in Intermix mode and a Class 1 Connectlon IS created to the other N-Port. 28.3 Topology models a * An N-Port may be attached directly to another N-Port through a point to point connection or through a Fabric. The topology may be deter- mined using the explicit Login procedure. Topology may also be determined by a method not defined by FC-PH. 28.3.1 Fabric model The N-Pot-t behavior described in this clause is based on a Fabric model in which an F-Port acts as the control point for establishing and removing Class 1 connections on behalf of the locally attached N-Port. The N-Port relies on specific behavioral characteristics in order to base its operation. The following terminology is used in the dis- cussion of Connection management. N-Port (A), (B), or (X) describe three separate N-Port Identi- fiers where A # B # X. The side of the F-Port directly attached to the N-Port side is termed its “Link” side, whereas attached internally to “internal” side. ANSI X3.230-1994 the side of the F-Port the Fabric is termed its The following F-Pot-t characteristics are required behavior: a) When an F-Port is not connected, it may receive a connect-request and begin proc- essing that request. The process of acting on that request is termed accepting the connect- request. b) After an F-Pot-t has accepted a connect- request from the Link, it reserves Fabric resources as it attempts to establish the requested Dedicated Connection. - the F-Port is Busy to other connect- requests from its internal side as destina- tion N Port. - the F-Port returns an F_BSY with EOFdt to the Link if a busy condition is encount- ered. (If a Fabric supports stacked connect-requests, the period of time before issuing an F_BSY may be extended.) - the F-Port returns an F_RJT with EOFdt to the Link if a reject condition is satisfied. c) After an F-Pot-t has accepted a connect- request from the internal side: - it passes the connect-request to the Link as the destination N-Port. - it monitors its Link side for a proper con- firmation response frame expected in response to the delivered connect-request. - it discards connect-request frames (SOFci) received from its Link side. (If the Fabric supports stacked connect-requests, the connect-request received from its Link side shall be stacked for establishing a Dedicated Connection at a later time.) d) If an F-Pot-t encounters a collision case wherein connect-requests from both the internal side and the Link side arrive simul- taneously, the F-Port accepts the connect- request from the internal side and proceeds as in step c above. e) If a failure is detected within a Fabric such that a Dedicated Connection can no longer be used, the Fabric may notify each of the F-Ports attached to the N-Ports involved in an established or pending Dedicated Connection and each of the F_Ports may then transmit the 249
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`ANSI X3.230-1994 Link Reset Primitive attached N-Port (i.e., tocol). Sequence to its locally initiate Link Reset Pro- f) See 16.4 for information on the effect of Prim- itive Sequences on F_Ports. 28.3.2 Point to Point model A point to point topology is indicated during the Login procedure. Two N-Ports arranged in a point to point connection may choose to: - establish one Dedicated Connection for the duration of an operating period, or - establish and remove Dedicated Con- nections dynamically, as the need to commu- nicate arises. ‘* 28.4 Connect / disconnect rules -. _2_8.4.1 Connect-request rules -- . The following sections specify the rules gov- %-ning the behavior of the source and destina- tion of the connect-request. 28.4.1 .I Source of connect-request The following rules specify the connect-request procedure as the source (A) of the connect- _ request: a) An N-Port (A) shall initiate a connect-request using a Data (Device-Data or Link-Data) frame with an SOFCI delimiter directed to des- tination N-Port (B). The connect-request frame is formed as follows: - an SOFcl delimiter - a Data (Device-data or Link-Data) frame - an S-ID of (A) and a D-ID of(B) - the E-C bit (F_CTL bit 18) shall be set = 0 - the Unidirectional bit (F_CTL bit 8) shall be set = 0 for a bidirectional Connection, and = 1 for a unidirectional Connection - an EOFn ending delimiter b) The Data Field of the connect-request shall be limited to the smaller of - the maximum buffer-to-buffer Receive-Data-Field size specified by the Fabric, if present, or - the maximum Receive-Data-Field size specified by the destination N-Port. 250 c) After N-Port (A) transmits the connect- request frame, N-Port (A) shall wait for a response frame before transmitting another frame for this Sequence. Additional Sequences for this Connection shall not be initiated until the Dedicated Connection is established. d) A Dedicated Connection is established when the connect-request frame has been responded to by an ACK frame. A proper response frame consists of: - an ACK_l or ACK_N frame with - an SOFnl delimiter, and - an S-ID of(B), and a D-ID of (A) - an EOFn, or EOFt delimiter e) An alternate response frame is also possible from the destination N-Port: - a P_BSY or P_RJT frame with - an SOFnl delimiter, - an S-ID of(B), and a D-ID of (A), and - an EOFdt delimiter. f) An alternate response frame is also possible from the Fabric: - an F_BSY or F_RJT frame with - an SOFnl delimiter, - an S-ID of(B), and a D-ID of (A), and - an EOFdt ending delimiter. g) After a Dedicated Connection is established, N-Port (A) shall be the Connection Initiator and N-Port (B) shall be the Connection Recip- ient. h) After a Dedicated Connection is established (i.e., the ACK to the connect-request has been received), the Connection Initiator, N-Port (A), may continue transmitting its initial Sequence and initiate other Sequences with SOFii up to N-Port (B)‘s ability to support Concurrent Sequences. 28.4.1.2 Destination of connect-request The following rules specify the connect-request procedure at the destination (B) of the connect- request: a) If a Data frame started by SOFcl is received when N-Port (B) is not connected and N-Port (B) is busy, N-Port (B) responds with P_BSY with an EOFdt delimiter as specified in 28.4.1.1 item number e. b) If a Data frame started by SOFCI is received when N-Pot-l (B) is not connected and N-Port
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`(B) rejects the connect-request, N-Port (B) responds with P_RJT with an EOFdt delimiter as specified
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`28.4.1.1 item number e. c) If a Data frame started by SOFCI is received when N-Port (B) is not connected and not busy, N-Port (B) responds with the proper response frame. A proper response frame is defined in 28.4.1.1 item number d. A Dedicated Connection is established with N-Port (A). N-Port (B) shall be the Con- nection Recipient and N-Port (A) shall be the Connection Initiator. d) With a Fabric present, if N-Port (B) receives a connect-request frame from N-Port (X) after a connect-request has been transmitted by N-Port (B), N-Port (B) requeues its own request for transmission at a later time and responds with a proper response frame to N-Port (X). NOTE - N-Port (B) requeues its original connect- request because the Fabric has discarded it. N-Port (B) needs to adjust its end-to-end Credit_CNT to account for the discarded connect- request. If stacked connect-requests are being employed, the connect-request shall not be requeued by N-Port (B). A Dedicated Connection N-Pot-t (X) with N-Port * Recipient. is established with (B) as Connection e) Without a Fabric present, if N-Port (B) accepts a connect-request frame from N-Port (A) after a connect-request has been trans- mitted by N-Port (B), N-Port (B) shall respond as follows: 1) if A > B, in value, - N-Port (B) requeues its own request for transmission at a later time, - responds to (A) with a proper response frame, - a Dedicated Connection is established with N-Port (A) with N-Port (B) as Con- nection Recipient, and - N-Port (B) may reinitiate its connect- request Sequence using SOFil. 2) if A < B, in value, - N-Port (B) discards connect-request from (A), and ANSI X3.230-1994 - waits for a proper response frame. r) After a Dedicated Connection is established (i.e., the ACK to the connect-request is trans- mitted), N-Port (B) may begin initiating Sequences with SOFti up to the destination N-Port’s ability to support Concurrent Sequences when the Connection is bidirectional. 28.4.2 Connection Rules a) If a bidirectional Connection is established (F_CTL bit 8 = 0 on connect-request), it shall remain bidirectional for the life of the Con- nection. b) If a unidirectional Connection is established (F_CTL bit 8 = I), it shall remain unidirectional until the Connection Initiator sets F_CTL bit 8 = 0, if ever, on the first or last frame of a Sequence (see 18.5) subse- quent to the connect-request frame. c) If a unidirectional Connection is made bidirectional, it shall remain a bidirectional Connection for the life of the Connection. d) The Connection Recipient may request that a unidirectional Connection be made bidirectional by setting F_CTL bit 8 = 0 on an ACK in response to a Data frame. Once F_CTL bit 8 is set to 0 on an ACK, it shall remain set to 0 for the life of the Connection. 28.4.3 Remove Connection rules a) An Active Sequence is complete when the corresponding ACK response to the last Data frame has been transmitted by the Sequence Recipient from the Recipient’s perspective and has been received by the Sequence Initi- ator from the Initiator’s perspective. b) If an N-Port detects an abnormal condition which requires immediate removal of an existing Connection, the N-Port shall use the Remove Connection (RMC) Basic Link Service frame with the appropriate F_CTL bit settings which includes setting the E-C bit = 1 in order to remove the Dedicated Connection. All Open and Active Class 1 Sequences are abnormally terminated and left in an indeter- minate state relative to the Upper Level Pro- tocol. RMC shall not be used in place of Link Reset in protocols which require Link Reset. 251
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`ANSI X3.230-1994 c) An N-Port shall transmit the E-C bit in F_CTL set to one on the last Data frame of a Sequence to indicate: - it is ready to end the Connection, - it shall not initiate any new Sequences, and - it requests the other N-Port to complete its Active Sequences and not initiate any new Sequences. d) If an N-Port has transmitted the E-C bit in F_CTL set to one and it receives a Data frame initiating a new Sequence, it shall respond as though the Sequence had been initiated before the E-C bit had been transmitted as one. e) If an N-Port has transmitted the E_,C bit in F_CTL set to one and it receives the last Data ‘e frame of a Sequence with the Chained-Sequence (C-S) bit in F_CTL set to one, it shall respond as though it had not pre- viously transmitted the E-C bit (it shall set the E C bit on a future Sequence). . --- -- _ _f) If either the Connection Initiator or Con- _nection Recipient has completed its last Active Sequence of the existing Connection and it receives a Data frame with E-C set to one, it shall transmit the corresponding ACK with an EOFdt delimiter. - the Connection Initiator shall transmit the ACK with the EOFdt delimiter. 28.5 Establishing a Connection A Dedicated Connection is established with an N-Port as the source of a connect-request (Con- nection Initiator) or as the destination N-Port (Connection Recipient) of a connect-request from another Class 1 N-Port. 28.51 Connection Initiator When FC-2 receives a request from an FC-4 or upper level to initiate a Class 1 Sequence when a Dedicated Connection does not exist, the N-Port shall also establish a Class 1 Connection with the destination N-Port as part of the Sequence initiation. The N-Port (A) initiates the connect-request using a Data (Device-Data or Link-Data) frame with an SOFcl delimiter. The Data Field size is limited to the smaller of: a) the maximum buffer-to-buffer Receive-Data-Field size specified by the Fabric, if present, or b) the maximum Receive-Data-Field size speci- fied by the destination N-Port. g) If either the Connection Initiator or Con- nection Recipient receives a Data frame with - the E-C bit set to one and it has not com- pleted all of Its Active Sequences, it - does not initiate any new Sequences (unless C-S bit is received), - completes Active Sequences, - transmits the E-C bit set to one on the last Data frame of its last Active Sequence for the Connection. h) If an N-Port encounters a collision case wherein a Data frame has been transmitted with E-C set to one and a Data frame is received with E-C set to one before receiving its ACK, After the N-Port transmits the connect-request frame, no additional frames shall be transmitted for any Sequence for the pending Connection until a response frame has been received. The N-Pot-t receives an R_RDY Primitive in response to the connect-request to indicate successful delivery to the F-Port or N-Port and that a buffer is available for a connectionless frame. If an N-Port is not operating in Intermix mode, the N-Port shall not transmit Class 2 or 3 frames _ until the pending Dedicated Connection is removed. A Dedicated Connection is not estab- lished until a proper ACK frame is received from the destination N-Port. A proper ACK frame is defined in 28.4.1.1 item number d. - the Connection Recipient shall respond with an ACK with an EOFt delimiter, whereas - the Connection Initiator shall withhold transmitting ACK until after its Sequence is complete. Table 111 defines Event 1 as the connect-request and events 2 through 9 define the possible responses. 252
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`ANSI X3.230-1994 -s - - Event 1. 2. 3. 4. 5. 6. 7. Table 111 - Responses to connect-request (SOFcl) SOF D-ID S-ID Frame EOF N-Pot-t Action SOFcl B A Data EOFn -Transmit connect-request frame -Wait for confirmation frame SOFnl A B F_BSY EOFdt Connection failed, Busy in Fabric SOFnl A B P_BSY EOFdt Connection failed, Busy in N-Port SOFnl A B F_RJT EOFdt Connection failed, Fabric Reject SOFnl A B P_RJT EOFdt Connection failed, Port Reject SOFnl A B ACK_l EOFn -Dedicated Connection established or -Continue transmitting Sequence ACK_N EOFt -Sequence ended, Connection established SOFcl A B Data EOFn N-Port A responds as follows frame PTP: If A > B in value, -discard B’s frame and wait for ACK response. -Dedicated Connection established with B. PTP: If A C B in value, -respond with SOFnl on ACK -Dedicated Connection established with B. -retransmit request assoc with event 1 with SOF
`SOFcl A X Data EOFn Fabric is present. frame -Requeue request assoc with event 1 (unless stacked connect-requests used) -Respond with SOFnl on ACK 1 or ACK_N. -Dedicated Connection established with X. 9. -Timeout, no response frame. -Perform Link Reset Protocol. (see 16.65) Event 1 Event 5 A connect-request is transmitted by N-Pot-t (A) with an SOFCI delimiter with a destination of N-Port (B). Event 2 A P_RJT indicates that the destination N-Port is unable to establish the Dedicated Connection. The reason code specifies the cause. Event 6 An F_BSY indicates that the Fabric is unable to access the destination N-Port due to a busy con- dition internal to the Fabric. Try again later. A Dedicated Connection has been established. N-Port (A) is Connected to N-Pot-t (B). Event 3 a) N-Port (A) is the Connection Initiator and N-Port (B) is the Connection Recipient. A P_BSY indicates that the destination N-Port link facility is temporarily occupied with other activity and unable to accept the connect- request. Try again later. b) N-Port (A) may continue transmitting the Sequence initiated (EOFn), or the Sequence which initiated the Connection may be com- plete (EOFt). Event 4 An F_RJT indicates that the Fabric is unable to establish the Dedicated Connection. The reason code specifies the cause. c) N-Port (A) may initiate other Sequences with the same destination N-Port (B) up to the maximum number of Sequences defined by the Serv