NSIS X. Fu Internet-Draft Univ. Goettingen Expires:May 11,August 25, 2005 H. Tschofenig T. Tsenov SiemensNovember 10, 2004February 21, 2005 QoS NSLP State Machinedraft-fu-nsis-qos-nslp-statemachine-00.txtdraft-fu-nsis-qos-nslp-statemachine-01.txt Status of this Memo This document is an Internet-Draft and is subject to all provisions ofsectionSection 3 of RFC 3667. By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she become aware will be disclosed, in accordance with RFC 3668. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire onMay 11,August 25, 2005. Copyright Notice Copyright (C) The Internet Society(2004).(2005). Abstract This document describes the state machines for the NSIS Signaling Layer Protocol for Quality-of-Service signaling (QoS NSLP). A set of state machines for QoS NSLP entities at different locations of a flow path are presented in order to illustrate how QoS NSLP may be implemented. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . ..3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . ..4 3. Notational conventions used in state diagrams . . . . . . ..5 4. State Machine Symbols . . . . . . . . . . . . . . . . . . ..7 5. Common Rules . . . . . . . . . . . . . . . . . . . . . . . ..8 5.1 Common Procedures . . . . . . . . . . . . . . . . . . . . 8 5.2 Common Variables . . . . . . . . . . . . . . . . . . . . . 8 5.3 Constants . . . . . . . . . . . . . . . . . . . . . . . . 9 5.4 Assumptions . . . . . . . . . . . . . . . . . . . . . . . 9 6. State machine forfirstQNI QoS NSLP nodein the flow path. . . . . . . . . . . . 10 7. State machine forintermediateQNE QoS NSLP nodes . . . . . . . . . . . . 13 8. State machine forlastQNR QoS NSLP nodein the flow path. . . . . . . . . . . . 17 9. Security Considerations . . . . . . . . . . . . . . . . . .. 1920 10. Open Issues . . . . . . . . . . . . . . . . . . . . . . . .2021 11.AcknowledgmentsChange History . . . . . . . . . . . . . . . . . . . . . .21 12. References. 22 11.1 Changes in Version -01 . . . . . . . . . . . . . . . . . 22 12. Acknowledgments . . . . . . . .22 12.1 Normative. . . . . . . . . . . . . . 23 13. References . . . . . . . . . . . . . . . . . . . .22 12.2 Informative. . . . . 24 13.1 Normative References . . . . . . . . . . . . . . . . . . 24 13.2 Informative References . . .22. . . . . . . . . . . . . . 24 Authors' Addresses . . . . . . . . . . . . . . . . . . . . .. 2224 Intellectual Property and Copyright Statements . . . . . . .. 2426 1. Introduction This document describes the state machines for QoS NSLP [1], trying to show how QoS NSLP can be implemented to support its deployment. The state machines described in this document are illustrative of how the QoS NSLP protocol defined in [1] may be implemented for thefirstQNI QoS NSLPnode in the flow path, intermediatenode, QNE QoS NSLP nodes, andthe lastQNR QoS NSLP node in the flow path. Where there are differences [1] are authoritative. The state machines are informative only. Implementations may achieve the same results using different methods. According to [1], there are several possibilities for QoS NSLP signaling, at least including the following: end-to-end signaling vs. scoped signaling sender-initiated signaling vs. receiver-initiated signaling (which need to be incorporated into use scenarios when describing state machine. Note they are represented by way of certain objects/flags in Reserve and Query messages.) The messages used in the QoS NSLP protocol can be summarized as follows: Requesting message Responding message ------------------------+--------------------------- RESERVE |None or RESERVE or RESPONSE QUERY |RESERVE or RESPONSE RESPONSE |NONE NOTIFY |NONE ------------------------+--------------------------- We describe a set of state machines for different roles of entities running QoS NSLP to illustrate how QoS NSLP may be implemented. 2. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [2]. 3. Notational conventions used in state diagrams The following text is reused from [3] and the state diagrams are based on the conventions specified in [4], Section 8.2.1. Additional state machine details are taken from [5]. The complete text is reproduced here: State diagrams are used to represent the operation of the protocol by a number of cooperating state machines each comprising a group of connected, mutually exclusive states. Only one state of each machine can be active at any given time. All permissible transitions between states are represented by arrows, the arrowhead denoting the direction of the possible transition. Labels attached to arrows denote the condition(s) that must be met in order for the transition to take place. All conditions are expressions that evaluate to TRUE or FALSE; if a condition evaluates to TRUE, then the condition is met. The label UCT denotes an unconditional transition (i.e., UCT always evaluates to TRUE). A transition that is global in nature (i.e., a transition that occurs from any of the possible states if the condition attached to the arrow is met) is denoted by an open arrow; i.e., no specific state is identified as the origin of the transition. When the condition associated with a global transition is met, it supersedes all other exit conditions including UCT. The special global condition BEGIN supersedes all other global conditions, and once asserted remains asserted until all state blocks have executed to the point that variable assignments and other consequences of their execution remain unchanged. On entry to a state, the procedures defined for the state (if any) are executed exactly once, in the order that they appear on the page. Each action is deemed to be atomic; i.e., execution of a procedure completes before the next sequential procedure starts to execute. No procedures execute outside of a state block. The procedures in only one state block execute at a time, even if the conditions for execution of state blocks in different state machines are satisfied, and all procedures in an executing state block complete execution before the transition to and execution of any other state block occurs, i.e., the execution of any state block appears to be atomic with respect to the execution of any other state block and the transition condition to that state from the previous state is TRUE when execution commences. The order of execution of state blocks in different state machines is undefined except as constrained by their transition conditions. A variable that is set to a particular value in a state block retains this value until a subsequent state block executes a procedure that modifies the value. On completion of all of the procedures within a state, all exit conditions for the state (including all conditions associated with global transitions) are evaluated continuously until one of the conditions is met. The label ELSE denotes a transition that occurs if none of the other conditions for transitions from the state are met (i.e., ELSE evaluates to TRUE if all other possible exit conditions from the state evaluate to FALSE). Where two or more exit conditions with the same level of precedence become TRUE simultaneously, the choice as to which exit condition causes the state transition to take place is arbitrary. In addition to the above notation, there are a couple of clarifications specific to this document. First, all boolean variables are initialized to FALSE before the state machine execution begins. Second, the following notational shorthand is specific to this document: <variable> = <expression1> | <expression2> | ... Execution of a statement of this form will result in <variable> having a value of exactly one of the expressions. The logic for which of those expressions gets executed is outside of the state machine and could be environmental, configurable, or based on another state machine such as that of the method. 4. State Machine Symbols ( ) Used to force the precedence of operators in Boolean expressions and to delimit the argument(s) of actions within state boxes. ; Used as a terminating delimiter for actions within state boxes. Where a state box contains multiple actions, the order of execution follows the normal language conventions for reading text. = Assignment action. The value of the expression to the right of the operator is assigned to the variable to the left of the operator. Where this operator is used to define multiple assignments, e.g., a = b = X the action causes the value of the expression following the right-most assignment operator to be assigned to all of the variables that appear to the left of the right-most assignment operator. ! Logical NOT operator. && Logical AND operator. || Logical OR operator. if...then... Conditional action. If the Boolean expression following the if evaluates to TRUE, then the action following the then is executed. \{ statement 1, ... statement N \} Compound statement. Braces are used to group statements that are executed together as if they were a single statement. != Inequality. Evaluates to TRUE if the expression to the left of the operator is not equal in value to the expression to the right. == Equality. Evaluates to TRUE if the expression to the left of the operator is equal in value to the expression to the right. > Greater than. Evaluates to TRUE if the value of the expression to the left of the operator is greater than the value of the expression to the right. <= Less than or equal to. Evaluates to TRUE if the value of the expression to the left of the operator is either less than or equal to the value of the expression to the right. ++ Increment the preceding integer operator by 1. 5. Common Rules Throughout the document we use terms defined in the [1], such as flow sender, flow receiver, QUERY, RESERVE or RESPONSE. 5.1 Common Procedures tx_RESERVE(Toff): Transmit RESERVE message with 'Teardown' bit off tx_RESERVE(Ton): Transmit RESERVE message with 'Teardown' bit on tx_RESPONSE(): Transmit RESPONSE messagetx_QUERY(w/RII):tx_QUERY(<object>): Transmit QUERY message withRequest Identification Information (RII) object tx_QUERY(w/oRII):<object> tx_QUERY(w/o<object>): Transmit QUERY message withoutRII object<object> tx_NOTIFY(): Transmit NOTIFY message rx_RESPONSE(): Receive RESPONSE message rx_QUERY(): Receive QUERY message rx_RESERVE(): Receive RESERVE messageTIMEOUT_State:rx_NOTIFY(): Transmit NOTIFY message TIMEOUT_StateLifetime: State lifetime timer expiration TIMEOUT_Refresh: Refresh interval timer expiration TIMEOUT_Refresh: Wait-Response interval timer expiration tg_QUERY: External trigger to send a QUERY message (typically triggered by the application). tg_RESERVE: External trigger to send a RESERVE message. tg_TEARDOWN: External trigger to clear previously established QoS state (typically triggered by the application). It is translated to a tx_RESERVE(Ton) message.SetInstall QoS state:establishInstall the local QoS state. Refresh QoS state:refreshRefresh the local QoS state.ClearDelete QoS state:deleteDelete the local QoS state. Send info to Application:reportReport information to the application. RMF: Performs Resource Management Function and returns the following values{AVAIL, NO_AVAIL}. SetRII: Sets the RII object of the messages e.g. the node requests explicit response to the message being sent. Returns values {0,1}. CheckRII: Checks the RII object of received RESPONSE message if it is requested by current node or other upstream node. Returns values {LOCAL, NO_LOCAL}.Result:ProcessQUERY: Processesthe information of the RESPONSE messagesa Query message and providesinformation. It tells whetherthereservation is successful or not (if it is a response to a reserve message), or the information carried in the response message (if it is a response to a query message), or an error has occurred. Returns values {INFO, SUCCESSFUL, ERROR}.requested info 5.2 Common Variables RII: Request Identification Information (RII) object. Logical variable representing if the RII is set or not. Takes values {0,1}. SCOPING: Scoping flag of common message header. Takes values {"Next_hop","Whole_path"}. RSN: Reservation Sequence Number object. Takes values: - recRSN - RSN object of the received message - currRSN - Current stored RSN value for installed QoS state. (Assumed to be the one for the direction where the message comes from e.g.Upstream/Downstream) ACK: Acknowledgement flag of common message header. Takes values {"On","Off"}. SummaryRefresh: Keeps information if Summary refresh method may be used for refreshing a installed QoS state. Takes value {"On","Off"}. E_SPEC: Error_Spec object. Takes values: - 0x02? - Success values - 0x04? - Transient Failure values - ERROR - Not specified in the QoS NSLP draft, but used here.(Section 10) QSPEC: QoS specification object. FlowID: Flow ID kept by the installed QoS state. Replace: Replace flag of common message header. Takes values {"On","Off"}. SII: Source Identification Information entry. Takes values: - CurrSII - SII entry stored for current installed QoS state. (Assumed to be the one for the direction where the message comes from e.g.Upstream/Downstream) - newSII - SII of the received message is different from the SII stored for the current installed QoS state. 5.3 Constants 5.4 Assumptions o For simplification not all included objects in a message are showed. Only those that are significant for the case are showed. State machines do not present handling of messages that are not significant for management of the states such as certain NOTIFY and QUERY messages. o State machines represent handling of messages of the same Session ID and with no protocol errors. Separate parallel instances of the state machines should handle messages for different Session IDs. o Default message handling should be defined for messages with different Session IDs that have impact on current session state and error messages. This is not included in the current version. o ACK flag in the common header is set "On" by default. o Direction of receiving and sending messages is not specified. We assume it is implicit from the context. 6. State machine forfirstQNI QoS NSLP nodein the flow path----------- State: INIT ----------- Condition Action State ------------------------+-------------------------+------------ UCT | initialize variables |IDLE ------------------------+-------------------------+------------ ----------- State: IDLE ----------- Condition Action State Note ------------------------+-------------------------+-----------+---(rx_QUERY) && (!RII) && |tx_NOTIFY(ERROR)rx_QUERY(RII) |ProcessQUERY |IDLE|1) (RMF="NO_AVAIL")| |tx_RESPONSE(RII) ||2) | | | (rx_QUERY) && (RII) |tx_RESPONSE(w/RII) |IDLE| | | | (tg_RESERVE) && |Send info to Application |IDLE | (RMF="NO_AVAIL") | | | | | |(tg_QUERY)(tg_RESERVE) &&(setRII) |tx_QUERY(w/RII) |WAITRESP1(!RII) |tx_RESERVE(w/oRII), |QoS state | && (!setRII) && | Install QoS state, |Installed | (RMF="AVAIL") |(tg_RESERVE) && (RII) &&|tx_RESERVE(w/RII) |WAITRESP2Send info to Application| |(RMF="AVAIL")| | | (tg_RESERVE) && (setRII)|Install QoS state, |QoS state | &&(RMF="AVAIL") | tx_RESERVE(RII) |Installed +| |(rx_QUERY) && (!RII) && |tx_RESERVE(w/RII)|WAITRESP2|2) (setRII) &&| | |(RMF="AVAIL")| (rx_QUERY)&&(!RII)&& |Tx_RESPONSE(RSN, |IDLE |1) (RMF="NO_AVAIL") | E_SPEC="ERROR") | |2) | | | (rx_QUERY) && (!RII) && |tx_RESERVE(w/oRII),|ESTABLISHED|2)|QoS state |2) (!setRII) && |SetInstall QoS state,||Installed | (RMF="AVAIL") | Send info to Application| | | | |(tg_RESERVE)(rx_QUERY) &&|tx_RESERVE(w/oRII), |ESTABLISHED| (!setRII)(!RII) &&| Set|Install QoS state, |QoS state |2) (setRII) && |tx_RESERVE( RII) |Installed +| (RMF="AVAIL") | |WAITRESP2 | | | | (tg_QUERY) && (setRII) |tx_QUERY(RII) |WAITRESP1 | |(RMF="AVAIL")|Send info to Application|| ------------------------+-------------------------+-----------+--- Note: 1)tx_NOTIFY(ERROR) is transmitted when an ERROR event must be announcedHow toother downstream nodes which do not expect a RESPONSE messagesignal unsuccessful reservation forthis action. E.g., there is no providedReceiver initiated reservation (No RIIwhich willincluded; sent Response(RSN) should not beincluded in a RESPONSE message;forwarded further than the next peer). No Error_SPEC value specified for this case. 2) Relevant for Receiver-initiated reservation. ---------------- State: WAITRESP1 ---------------- Condition Action State ------------------------+-------------------------+------------(TIMEOUT_Refresh)(TIMEOUT_WaitResp) &&|tx_RESERVE(w/RII)|tx_QUERY(RII) |WAITRESP1 (!MaxRetry) | | | |(TIMEOUT_Refresh)(TIMEOUT_WaitResp) && |Send info to Application |IDLE (MaxRetry) | | | | rx_RESPONSE |Send info to Application |IDLE ------------------------+-------------------------+-------------------------------------------------------------------- State:ESTABLISHED ------------------QoS state installed + WAITRESP2 -------------------------------------- Condition Action State ------------------------+-------------------------+------------TIMEOUT_Refresh |tx_RESERVE |ESTABLISHED(TIMEOUT_WaitResp) && |tx_RESERVE(RII) |QoS state (!MaxRetry) | |installed + |tg_TEARDOWN |tx_RESERVE(Ton),|WAITRESP2 | | | | (TIMEOUT_WaitResp) && |Delete QoS state |IDLE (MaxRetry) |Send info to Application | | |Clearrx_RESPONSE(RII, |Delete QoS state |IDLE E_SPEC="0x04?") |Send info to Application | | | | | rx_RESPONSE(RII, |Send info to Application |QoS state E_SPEC="0x02?") |SummaryRefresh="On" |installed ------------------------+-------------------------+------------------------------------------------------ State:WAITRESP2 ----------------QoS state installed -------------------------- Condition Action State------------------------+-------------------------+------------ (TIMEOUT_Refresh)Note ------------------------+-------------------------+-----------+--- TIMEOUT_Refresh |If (SummaryRefresh="On") |QoS state | | (Tx_RESERVE(RSN)) &&|tx_RESERVE(w/RII) |WAITRESP2 (!MaxRetry)|installed | | (SummaryRefresh="Off") | |(TIMEOUT_Refresh) && |Send info to Application |IDLE (MaxRetry)|Else | | | Tx_RESERVE(RSN,QSPEC); |(rx_RESPONSE) &&| | | | rx_RESPONSE(RSN, |SummaryRefresh="On" |QoS state | E_SPEC="0x02?") | |installed | | | | TIMEOUT_StateLifetime |Delete QoS state |IDLE |1) |Send info to Application|IDLE (Result="ERROR")| | | |(rx_RESPONSE) && |Set| tg_TEARDOWN |Delete QoS state,|ESTABLISHED (Result="SUCCESS")&&|IDLE |Send| tx_RESERVE(Ton) | | | | | rx_NOTIFY(RSN, |Delete QoS state |IDLE | E_SPEC="0x04?") |Send info toApplication| (RMF="AVAIL")Application | |------------------------+-------------------------+------------------------------------+-------------------------+-----------+--- Note: 1) If QoS state lifetime expires in QNI, should RESERVE(Ton) be sent downstream the path? 7. State machine forintermediateQNE QoS NSLP nodes ----------- State: INIT ----------- Condition Action State ------------------------+-------------------------+------------ UCT | initialize variables |IDLE ------------------------+-------------------------+------------ ----------- State: IDLE ----------- Condition Action State Note ------------------------+-------------------------+-----------+---(rx_RESERVE)&& !((RII)&&|Set QoS state, |ESTABLISHED|1a) (setRII))(rx_QUERY) &&| tx_RESERVE(w/oRII)(!RII) |tx_QUERY(w/oRII) |IDLE |2) | |(RMF="AVAIL")| (rx_QUERY(RII, |ProcessQUERY, |IDLE |7) SCOPING="Next_hop") |Tx_RESPONSE(RII) | | | | |(rx_RESERVE)(rx_QUERY) && (RII)&&|Set QoS state, |ESTABLISHED|1b) (RMF="AVAIL") &&|tx_QUERY(w/RII) |IDLE |7) |tx_RESPONSE(w/RII)| |(SCOPING="Next_hop")(rx_RESERVE(RII)) && |Tx_RESPONSE(RII, |IDLE |3) (RMF="NO_AVAIL") | E_SPEC="0x04?") | | | | | (rx_RESERVE) &&(!RII)&&|Set QoS state |ESTABLISHED|1b) (RMF="AVAIL") &&(!RII)&&|Tx_RESPONSE(RSN, |IDLE |3) (RMF="NO_AVAIL") | E_SPEC="0x04?") | |(SCOPING="Next_hop")| | | (rx_RESPONSE(RII)) && |Tx_RESPONSE(RII) |IDLE | (CheckRII="Not_LOCAL")| | |(rx_QUERY) && (!RII) |tx_QUERY(w/oRII) |IDLE |2)| | |(rx_QUERY)(rx_RESERVE)&& !(setRII)|Install QoS state, |QoS State |1a) &&|tx_QUERY(w/RII) |IDLE(RMF="AVAIL") |If(ACK="On") |Installed |(SCOPING="Next_hop")| Tx_RESPONSE(RSN, | | | E_SPEC="0x02?");| | |If(RII) Tx_RESPONSE(RII) |(rx_RESERVE)| |Else Tx_RESPONSE(w/oRII)| | | | | (rx_RESERVE(SCOPING= |Install QoS state, |QoS State |1b) "Next_hop")) &&(RII)&& |tx_RESPONSE(RII, ERROR) |IDLE |3) (RMF="NO_AVAIL")|If(RII) Tx_RESPONSE(RII, |Installed | (RMF="AVAIL") | E_SPEC="0x02?") | | |Else Tx_RESPONSE(RSN, | |(rx_RESERVE) && (!RII)&&|tx_NOTIFY(ERROR) |IDLE |3) (RMF="NO_AVAIL")| E_SPEC="0x02?") | | | | | (rx_RESERVE) &&((RII)|||tx_RESERVE(w/RII) |WAITRESP1(setRII)|Install QoS state, |QoS State |4)(setRII))&&| | |(RMF="AVAIL") |Tx_RESPONSE(RII), |Installed +| |If(ACK="On") |WAITRESP1 | | Tx_RESPONSE(RSN, | | | E_SPEC="0x02?");| |(rx_QUERY) && (RII) |tx_QUERY(w/RII) |WAITRESP2 |5)| | | (tg_QUERY) && (setRII)|tx_QUERY(w/RII)|tx_QUERY(RII) |WAITRESP2 |5) ------------------------+-------------------------+-----------+------------------------------------- State:ESTABLISHED ------------------QoS State Installed + WAITRESP1 ---------------- Condition Action State------------------------+-------------------------+------------ rx_RESERVE(Ton) |tx_RESERVE(Ton), |IDLENote ------------------------+-------------------------+-----------+--- (TIMEOUT_WaitResp) && |tx_RESERVE(RII) |WAITRESP1 |clear QoS state(!MaxRetry) | | |TIMEOUT_Refresh |Refresh| | | (TIMEOUT_WaitResp) && |Delete QoSstate; |ESTABLISHEDState, |if state changes,| (MaxRetry) && |tx_NOTIFY(RSN, |IDLE |tx_RESERVE(w/RII)| E_SPEC="0x04?") | |TIMEOUT_State |Clear|Send info to Application | | | | | (rx_RESPONSE(RII, |Delete QoSstateState, |IDLE------------------------+-------------------------+------------|4) E_SPEC="0x04?")) |tx_NOTIFY(RSN, | | &&(CheckRII="LOCAL") | E_SPEC="0x04?") | | |Send info to Application | | | | | (rx_RESPONSE(RII, |Send info to Application |QoS State | E_SPEC="0x02?")) |SummaryRefresh="On" |Installed | &&(CheckRII="LOCAL") | | | ------------------------+-------------------------+-----------+--- ---------------- State:WAITRESP1WAITRESP2 ---------------- Condition Action State------------------------+-------------------------+------------ (TIMEOUT_Refresh)Note ------------------------+-------------------------+-----------+--- (TIMEOUT_WaitResp) &&|tx_RESERVE(w/RII) |WAITRESP1|tx_QUERY(RII) |WAITRESP2 | (!MaxRetry) |Send info to Application|| |(TIMEOUT_Refresh)| | | (TIMEOUT_WaitResp) &&|tx_NOTIFY(ERROR),|Send info to Application |IDLE | (MaxRetry)&&|Send| | | | | (rx_RESPONSE) && |Send info toApplication|IDLEApplication |IDLE | (CheckRII="LOCAL") | | | ------------------------+-------------------------+-----------+--- ------------------ State: QoS State Installed ------------------ Condition Action State Note ------------------------+-------------------------+-----------+--- rx_RESERVE(Ton) |tx_RESERVE(Ton), |IDLE |(TIMEOUT_Refresh) && |tx_RESPONSE(w/RII,Result=| (MaxRetry) &&|Delete QoS state |"ERROR") |IDLE (CheckRII="NO_LOCAL")|| | |(rx_RESPONSE) && |Set| rx_RESERVE |Refresh QoS state|ESTABLISHED (CheckRII="LOCAL")&&|QoS State |6) |If(ACK="On") |Installed | |Tx_RESPONSE(RSN, |(Result="SUCCESS")| | E_SPEC="0x02?") | |(rx_RESPONSE) && |Set QoS state, |ESTABLISHED (CheckRII="NO_LOCAL")| tx_RESPONSE(RII)|&&(Result="SUCCESS")| | rx_RESPONSE(RSN, |SummaryRefresh="On" |QoS State |6) E_SPEC="0x02?") | |Installed |(rx_RESPONSE) && |tx_NOTIFY(ERROR), |IDLE (CheckRII="LOCAL")&&|send info to Application| (Result="ERROR")| | TIMEOUT_Refresh |If (SummaryRefresh="On") |QoS State |6) | (Tx_RESERVE(RSN)) |Installed |(rx_RESPONSE) && |tx_RESPONSE(w/RII) |IDLE (CheckRII="NO_LOCAL")||&&(Result="ERROR")&&(SummaryRefresh="Off")| | |Else |------------------------+-------------------------+------------- ---------------- State: WAITRESP2 ---------------- Condition Action| | Tx_RESERVE(RSN,QSPEC) | | | | | (rx_RESPONSE(RII, |SummaryRefresh="On" |QoS State------------------------+-------------------------+------------ (TIMEOUT_Refresh) && |tx_QUERY(w/RII) |WAITRESP2 (!MaxRetry)| E_SPEC="0x02?")) |Tx_RESPONSE(RII, |Installed | &&(ChechRII="NOT_LOCAL")| E_SPEC="0x02?") | |(TIMEOUT_Refresh) && |Send info to Application| | | | | | (TIMEOUT_StateLifetime) |Delete QoS state |IDLE(MaxRetry) &&|8) | |(CheckRII="LOCAL")| (rx_RESPONSE(RII, | | |(TIMEOUT_Refresh) && |tx_RESPONSE(Result=E_SPEC="0x04?")) |Delete QoS state |IDLE(MaxRetry) &&|"ERROR")&&(ChechRII="NOT_LOCAL")|rx_RESPONSE(RII, |(CheckRII="NO_LOCAL")|| | E_SPEC="0x04?") |(rx_RESPONSE) && |Send info to Application| | | | rx_RESPONSE(RSN, |Delete QoS state |IDLE(CheckRII="LOCAL")| E_SPEC="0x04?") |rx_NOTIFY(RSN, | | |(rx_RESPONSE) && |tx_RESPONSE(w/RII)E_SPEC="0x04?") | | | | | rx_NOTIFY(RSN, |Delete QoS state |IDLE(CheckRII="NO_LOCAL")||------------------------+-------------------------+------------- Note:E_SPEC="0x04?") |rx_NOTIFY(RSN, | | | E_SPEC="0x04?") | | | | | | | | (Rx_RESERVE)&&(currSII) |Update QoS state |QoS State |9) &&(Replace="On") |If (RII) |Installed | &&(RMF="AVAIL") | Tx_RESERVE(RII,QSPEC)| | &&((recRSN>=currRSN) |else | | ||(newFlowID)) | Tx_RESERVE(RSN,QSPEC);| | |If (ACK="On")&&(!RII) | | | tx_RESPONSE(RSN, | | | E_SPEC="0x02?");| | | | | | | | (Rx_RESERVE)&&(newSII) |Update QoS state |QoS State |9) &&(RMF="AVAIL") |If (RII) |Installed | &&((recRSN>=currRSN) | Tx_RESERVE(RII,QSPEC)| | ||(newFlowID)) |else | | | Tx_RESERVE(RSN,QSPEC);| | |If (ACK="On")&&(!RII) | | | tx_RESPONSE(RSN, | | | E_SPEC="0x02?");| | |If (Replace="On") | | | tx_Reserve(Ton) | | | to currSII | | ------------------------+-------------------------+-----------+--- NOTE: 1) Successful reservationwith responsewithout Response request (1a) and with Scoping(1b);(1b). 2) Processing of Query msg for Receiver initiatedreservation;reservation 3) Unsuccessful reservationfor Receiver initiated reservation,with/without request for response fromthe flow sender side. Tx_NOTIFY(ERROR) is sent to the upstream nodes to indicate failure of the reservationprevious node in thecase when no RESPONSE is required by them;path. 4)Reservation requests withUnsuccessful reservation. RIIset inrequested at the local node. NOTIFY(RSN) is sent further to the upstreamnodes or in this node;nodes. 5) Processing of Querymessage received from a neighboring node ormsg triggered by the application layer. 6) QoS State refresh procedures 7) Processing of Query msg received from an upstream node. 8) We assume that handling of QoS state lifetime expiration event is based on the local policy of the node. NOTIFY/Reserve(Ton) messages might be sent to other peers. These issues are not described in the QoS NSLP draft. 9) Update QoS state and Re-route functionality 8. State machine forlastQNR QoS NSLP nodein the flow path----------- State: INIT ----------- Condition Action State ------------------------+-------------------------+------------ UCT | initialize variables |IDLE ------------------------+-------------------------+------------ ----------- State: IDLE ----------- Condition Action State Note ------------------------+-------------------------+-----------+--- rx_QUERY(RII) |tx_RESPONSE(RII) |IDLE | | | | (rx_RESERVE)&&(!RII) |Tx_RESPONSE(RSN, |IDLE | && (RMF="NO_A") | E_SPEC="0x04?") | | | | | | | | (rx_RESERVE(RII)) |Tx_RESPONSE(RII, |IDLE | && (RMF="NO_A") | E_SPEC="0x04?") | | | | | (tg_QUERY) &&|tx_QUERY(w/RII)|tx_QUERY(w/oRII) |WAITRESV |1) (!setRII) | | | | | |(rx_RESERVE) && (RII) &&|Set| | | (rx_RESERVE(RII)) |Install QoSstate, |ESTABLISHED|2a)state |QoS state |2) && (RMF="AVAIL") |Tx_RESPONSE(RII, |installed |tx_RESPONSE(w/RII)| E_SPEC="0x02?") | | | |(rx_RESERVE) && (!RII)&&|Set| (rx_RESERVE)&&(!RII) |Install QoS state|ESTABLISHED|2b)|QoS state |2) && (RMF="AVAIL") |Tx_RESPONSE(RSN, |installed | E_SPEC="0x02?") | | ------------------------+-------------------------+-----------+--- --------------- State: WAITRESV --------------- Condition Action State Note ------------------------+-------------------------+-----------+--- TIMEOUT_WaitResp |Tx_QUERY(w/oRII) |WAITRESV | | |(tg_RESERVE) &&| (TIMEOUT_WaitResp) |Send info toApplicationAppl. |IDLE|3) (RMF="NO_AVAIL")| && (MaxRetry) | | | | |(rx_RESPONSE) && (RII)&&|tx_RESPONSE(RII, ERROR)| (rx_RESERVE)&&(!RII) |tx_RESPONSE(RSN, |IDLE |3) && (RMF="Not_AVAIL") |(RMF="NO_AVAIL")E_SPEC="0x04?") | | |Send info to Appl. | | | |(rx_QUERY) && (RII) && |tx_QUERY(w/RII)| (rx_RESERVE(RII)) |tx_RESPONSE(RII, |IDLE |3) && (RMF="Not_AVAIL") |------------------------+-------------------------+-----------+--- ------------------ State: ESTABLISHED ------------------ Condition Action State ------------------------+-------------------------+------------ rx_RESERVE |Refresh QoS state |ESTABLISHEDE_SPEC="0x04?") | |TIMEOUT_State |Clear QoS state |IDLE ------------------------+-------------------------+------------ --------------- State: WAITRESV --------------- Condition Action State Note ------------------------+-------------------------+-----------+--- (rx_RESPONSE) &&|Send info toApplicationAppl. | | | | | rx_RESPONSE(E_SPEC= |Send info to Appl. |IDLE |4) "ERROR")| |(Result="ERROR")| | | | | |(rx_RESERVE) && (!RII)&&|Set| (rx_RESERVE)&&(!RII) |Install QoS state|ESTABLISHED|2)|QoS state | && (RMF="AVAIL") |Tx_RESPONSE(RSN, |installed | | E_SPEC="0x02?") | | | |(rx_RESERVE) && (RII)&& |Set| (rx_RESERVE(RII)) |Install QoSstate, |ESTABLISHED|2)State |QoS state | && (RMF="AVAIL") |Tx_RESPONSE(RII) |installed |tx_RESPONSE(w/RII)| |(rx_RESERVE) && (RII) &&|tx_NOTIFY(ERROR), |IDLE |4) (RMF="NO_AVAIL")|Send info to Application|------------------------+-------------------------+-----------+--- ------------------ State: QoS state installed ------------------ Condition Action State Note ------------------------+-------------------------+-----------+--- rx_RESERVE |Refresh QoS state |QoS state | |If(ACK="On") |installed | | Tx_RESPONSE(RSN, |(rx_RESERVE) && (!RII)&&|tx_RESPONSE(RII,ERROR),| | E_SPEC="0x02?")| | | | | TIMEOUT_StateLifetime |Delete QoS state |IDLE|4) (RMF="NO_AVAIL")|5) |Send info to Application||------------------------+-------------------------+-----------+---| rx_RESERVE(Ton) |Delete QoS state |IDLE | | | | ------------------------+-------------------------+------------ Note: 1) Initiation ofreceiver-side reservation;Receiver-side reservation 2) Successfulreservation with&withoutReservation with& without response request fromsender side;the QNI side 3)In case of noUnsuccessful Reservation with & without responserequested (RIIrequest from the QNI side. 4) How to signal unsuccessful reservation for Receiver initiated reservation(No RII is included, received Response(RSN) should notpresent in RESERVE message), NOTIFY(ERROR) messagebe forwarded. 5) We assume that handling of QoS state lifetime expiration event is based on the local policy of the node. NOTIFY/Reserve(Ton) messages might be sentbacktothe upstream nodesother peers. These issues are not described inorder to clear already establishedthe QoSstate; 4) Unsuccessful reservation with&without response request from sender side;NSLP draft. 9. Security Considerations This document does not raise new security considerations. Any security concerns with the QoS NSLP are likely reflected in security related NSIS work already (such as [1] or [6]). For the time being, the state machines described in this document do not consider the security aspect of QoS NSLP protocol itself. A future versions of this document will add security relevant states and state transitions. 10. Open Issues This document tries to describe possible states and transitions for QoS NSLP according to its current specification [1], Section 5. We found some issues during the development of the state machines. o Forexample, forreceiver-initiated reservation, it is unclear who triggers ateardown; bi-directionalteardown. o Bi-directional reservation is difficult to support as the state machine becomes quite complex (note at one particular point in time the protocol state engine can be only in one state).Another example is, it is often ignoredo How to signal unsuccessful reservation forthe functionality of abort operation after a defined MaxRetry number of retries. Results of this type of transitions are dependent on the parameterReceiver initiated reservation (No RII(e.g., if it is locally set or not). There are further unclear issues with processing rules and message definition, e.g., soft state handling and how to process notification messages, which will be described in more detail inincluded; afuture version ofresulting Response(RSN) cannot be forwarded further than the next peer). No Error_SPEC value specified for thisdocument. To avoid confusions incase. o If QoS statemachines, instead oflifetime expires in QNI, should RESERVE(Ton) be sent downstream the path? o The case of unsuccessful reservation at a QNE node andQNR, in this documentno RII specified by upstream nodes. According to the spec RESPONSE(RSN) should not be forwarded further than the next peer. Currently we use NOTIFY(RSN) that is sent further to thenotationsupstream nodes. o We assume that handling of"firstQoSNSLP node instate lifetime expiration event is based on theflow path" (the closest one tolocal policy of theflow sender ornode. NOTIFY/Reserve(Ton) messages might be sent to other peers. These issues are not described in theflow sender itself), "intermediateQoS NSLPnodes"draft. o The draft states that RESERVE message MUST be sent only towards the QNR. This is not the case when re-routing procedure is done and"last QoS NSLPRESERVE(Ton) message should be sent from merging QNE node for deleting the old branch. We believe this is towards the QNI. o Re-routing functionality described in this document is not complete and need further consideration. 11. Change History 11.1 Changes in Version -01 Version -01 covers more functionalities of theflow path" (the closest one toQoS NSLP. This requires addition and changes of theflow receiver ornotations. The main details are as follows: 1. Notation of theflow receiver itself). Default rulesnodes changed to QNI, QNE andcommonQNR. 2. Description of soft statetransitions in caserefresh functionality. 3. Support ofreceptionACK flag in the common header. 4. Include ofcertain messages as Notify,QoS NSLP objects, flags from the common header andQuery(w/RII), will be describedentries stored with the installed QoS state in afuture versionnode: ACK, Replace, RSN, Error_SPEC, QSPEQ, FlowID, SII. 5. Initial description ofthis document. 11.Re-routing functionality (Section 10). 6. For support of all listed changes, some notations are changed. 12. Acknowledgments The authors would like to thank Sven Van den Bosch for his feedback.12.13. References12.113.1 Normative References [1] Bosch, S., Karagiannis, G. and A. McDonald, "NSLP for Quality-of-Service signaling",draft-ietf-nsis-qos-nslp-04 (work in progress), JulyInternet-Draft draft-ietf-nsis-qos-nslp-05, October 2004. [2] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", March 1997.12.213.2 Informative References [3] Vollbrecht, J., Eronen, P., Petroni, N. and Y. Ohba, "State Machines for Extensible Authentication Protocol (EAP) Peer and Authenticator",draft-ietf-eap-statemachine-05 (work in progress), SeptemberInternet-Draft draft-ietf-eap-statemachine-06, December 2004. [4] Institute of Electrical and Electronics Engineers, "DRAFT Standard for Local and Metropolitan Area Networks: Port-Based Network Access Control (Revision)", IEEE 802-1X-REV/D9, January 2004. [5] Ohba, Y., "State Machines for Protocol for Carrying Authentication for Network Access (PANA)",draft-ohba-pana-statemachine-00 (work in progress), July 2004.Internet-Draft draft-ohba-pana-statemachine-01, February 2005. [6] Tschofenig, H. and D. Kroeselberg, "Security Threats for NSIS",draft-ietf-nsis-threats-06 (work in progress),Internet-Draft draft-ietf-nsis-threats-06, October 2004. Authors' Addresses Xiaoming Fu University of Goettingen Telematics Group Lotzestr. 16-18 Goettingen 37083 GermanyEMail:Email: fu@cs.uni-goettingen.de Hannes Tschofenig Siemens Otto-Hahn-Ring 6 Munich, Bayern 81739 GermanyEMail:Email: Hannes.Tschofenig@siemens.com Tseno Tsenov Siemens Otto-Hahn-Ring 6 Munich, Bayern 81739 GermanyEMail:Email: tseno.tsenov@mytum.de Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. 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