One document matched: draft-ietf-ipfix-protocol-01.txt

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   IPFIX working group                                                  
   Internet Draft                               EDITORS:      B. Claise
   draft-ietf-ipfix-protocol-01.txt                       Cisco Systems 
   Expires: April 2004                                     Mark Fullmer 
                                                                 OARnet 
                                                            Paul Calato 
                                                    Riverstone Networks 
                                                         Reinaldo Penno 
                                                        Nortel Networks 
                                                           October 2003 
    
    
                       IPFIX Protocol Specifications  

                                      
    
 Status of this Memo 
    
   This document is an Internet-Draft and is in full conformance with 
   all provisions of Section 10 of RFC2026.  
    
   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 obsolete 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. 
     
 Abstract 
    
   This document discusses the IPFIX protocol that provides network 
   administrators with access to IP flows information. This document 
   focuses on how IPFIX flow record data, options record data and 
   control information is carried (via a congestion-aware transport 
   protocol) from IPFIX exporting process to IPFIX collecting process. 
    
    
 Conventions used in this document 
    




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   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 RFC 2119. 
    
 Table of Contents 
    
     1. Points of Discussion........................................3 
      1.1 Open Issues................................................3 
      1.2 Action Items...............................................4 
     2. Introduction................................................4 
      2.1 Overview...................................................4 
     3. Terminology.................................................4 
      3.1 Terminology Summary Table..................................9 
     4. The Metering Process........................................9 
      4.1 Flow Expiration............................................9 
     5. Transport Protocol.........................................10 
      5.1 TCP.......................................................10 
      5.2 STCP......................................................10 
     5.2.1  Congestion Avoidance..................................11 
     5.2.2  Reliability...........................................11 
     5.2.3  Exporting Process.....................................11 
     5.2.3.1 MTU size.............................................11 
     5.2.3.2 Source ID............................................11 
     5.2.3.3 Association..........................................12 
     5.2.3.4 Template.............................................12 
     5.2.3.5 Template.............................................12 
     5.2.4  Collecting Process....................................13 
     5.2.5  SCTP Partially Reliable...............................13 
     6. Failover...................................................14 
      6.1 Simple Failover based on the transport protocol...........14 
      6.2 Something else?...........................................14 
     7. Packet Layout..............................................14 
     8. Export Packet Format.......................................16 
      8.1 Header Format.............................................16 
      8.2 Template FlowSet Format...................................17 
      8.3 Data FlowSet Format.......................................19 
     9. Options....................................................20 
      9.1 Options Template FlowSet Format...........................20 
      9.2 Options Data Record Format................................22 
     10. Variable Length Data Type.................................24 
     11. Template Management.......................................25 
     12. The Collecting Process's Side.............................26 
     13. Examples..................................................27 
      13.1 Packet Header Example....................................28 
      13.2 Template FlowSet Example.................................28 
      13.3 Data FlowSet Example.....................................29 
      13.4 Options Template FlowSet Example.........................30 
      13.5 Data FlowSet with Options Data Records Example...........31 
     14. References................................................31 


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     15. Acknowledgments...........................................32 
      
      
 1. Points of Discussion 
    
 1.1 Open Issues 
    
   This section covers the open issues, still to be resolved/updated in 
   this draft: 
    
   - The proposal on the table is to send a IPFIX Sync (this would be 
   an Options Data Records) message periodically (periodicity is 
   configurable), with the following information (aside the standard 
   IPFix header) 
           * Number of flow records sent (for each template?)  
           * Packets and bytes sent (for each template?) 
     Question: Per observation domain? 
     Question: Do we need a specific FlowSet ID? 
   - Template don't need lifetimes with connection oriented protocol. 
   We guess this is the consensus from the Working Group. 
   - No periodic retransmission of templates is needed, with a reliable 
   transport protocol. 
   Remark: the template management will vary with TCP, SCTP, etcà 
   Must have both sections updated: transport updated and template 
   management sections (BTW, this is the same for the failover 
   section). 
   - There seems to be a consensus that having a length field in the 
   Export Packet header. 
   Related question: what about the count field then in the NetFlow 
   version 9 header? But no consensus yet. So no consensus whether the 
   current count should simply be replaced by the length or the length 
   field be added. 
   - Sub-second timestamps 
   - Export ID (ie IP address of exporter) sent to the collector. This 
   can be done once with an options template. 
   - Metering process stats: for example packets / flows dropped at the 
   metering process due to resource exhaustion, etcà This can be done 
   with an options template. 
   - Error recovery, for example what to do if a collector receives a 
   message it can't decode. Per protocol issue, ie TCP reset the 
   session because it's a stream protocol and can't recover. 
   - If we tackle reliablilty a state diagram is needed. 
   - Talk a little bit about extensibility, for example make some 



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   decisions now about the reserved template ID's 2-254 for future 
   work. 

 1.2 Action Items 
    
   This section covers the action items for this draft 
   - change the abstract: done, to be reviewed 
    -> Reinaldo 
   - introduction to be completed: introduction + references to other 
   drafts + applications for the protocol.  
    -> Reinaldo 
   - ôtransport protocolö section to be updated.  
      -> TCP, Reinaldo 
     Note: each transport protocol (TCP/SCTP) should have at least the 
   following subsections: Reliability, Failover, Template Management 
   - Review the requirements draft to see what we miss! 
     -> Benoit  
   - variable length data types 
      -> Text and packet format to be worked on. Benoit 
   - field types information -> should we have basic type in the 
   protocol draft, like Jeff suggested. 
      -> Mark: will send an abstract 
   - add references to the IPFIX drafts, when published 
    

 2. Introduction 
    
 2.1 Overview 
    
   Will be completed.  
   It will cover an introduction, pointers/explanation towards/of the 
   other drafts, and the applications for the IPFIX protocol  
    
 3. Terminology 

   The definitions of IP Traffic Flow, Metering Process, Exporting 
   Process and Collecting Process are the definitions as found in the 
   IPFIX requirement document [IPFIX-REQ]. Note nevertheless that,  
   even if the Observation Point definition has been also been 
   completely copied over from the IPFIX requirement document [IPFIX-
   REQ], this definition has been expanded. 
    
   The terminology summary table in Section 3.1 gives a quick overview 
   of the relationships between some of the different terms defined. 


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Observation Point 
    
   The Observation Point is a location in the network where IP packets 
   can be observed. Examples are a line to which a probe is attached, 
   a shared medium such as an Ethernet-based LAN, a single port of a 
   router, or a set of interfaces (physical or logical) of a router.  
   An Observation Domain is associated with every Observation Point.  
    
   Note that one Observation Point may be a superset of several 
   other Observation Points. For example one Observation Point can be 
   an entire line card. This would be the superset of the 
   individual Observation Points at the line card's interfaces.  
    
Observation Domain 
    
   The set of Observation Points, which is the largest aggregatable set 
   of Flow information at the Metering Process is termed an Observation 
   Domain. Each Observation Domain presents itself as a unique ID to 
   the Collecting Process for identifying the Export Packets it 
   generates.   
   For example, a router line card composed of several interfaces with 
   each interface being an Observation Point. 
    
IP Traffic Flow or Flow 
    
   There are several definitions of the term 'flow' being used by the 
   Internet community. Within this document we use the following one: 
    
   A Flow is defined as a set of IP packets passing an Observation 
   Point in the network during a certain time interval. All packets 
   belonging to a particular Flow have a set of common properties. Each 
   property is defined as the result of applying a function to the 
   values of: 
    
        1. one or more packet header field (e.g. destination IP 
        address), transport header field (e.g. destination port 
        number), or application header field (e.g. RTP header fields 
        [RFC1889]) 
        2. one or more characteristics of the packet itself (e.g. 
        number of MPLS labels, etc...) 
        3. one or more of fields derived from packet treatment (e.g. 
        next hop IP address, the output interface, etc...) 


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   A packet is defined to belong to a Flow if it completely satisfies 
   all the defined properties of the Flow. 
    
   This definition covers the range from a Flow containing all packets 
   observed at a network interface to a Flow consisting of just a 
   single packet between two applications with a specific sequence 
   number. Please note that the Flow definition does not necessarily 
   match a general application-level end-to-end stream. However, an 
   application may derive properties of application-level streams by 
   processing measured Flow data. Also, please note that although 
   packet properties may depend on application headers, there is no 
   requirement defined in this document related to application headers. 
    
 Flow Record  
  
   A Flow Record provides information about an IP Traffic Flow observed 
   at an Observation Point.  
    
Metering Process 
    
   The Metering Process generates Flow Records. Input to the process 
   are packet headers observed at an Observation Point and packet 
   treatment at the Observation Point, for example the selected output 
   interface. 
   The Metering Process consists of a set of functions that includes 
   packet header capturing, timestamping, sampling, classifying, and 
   maintaining Flow Records. 
    
   The maintenance of Flow Records may include creating new records, 
   updating existing ones, computing Flow statistics, deriving further 
   Flow properties, detecting Flow expiration, passing Flow Records to 
   the Exporting Process, and deleting Flow Records. 
    
   The sampling function and the classifying function may be applied 
   more than once with different parameters. Figure 1 shows the 
   sequence in which the functions are applied. Sampling is not 
   illustrated in the figure, it may be applied before any other 
   function. 
    
                              packet header capturing 
                                        | 
                                   timestamping 


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                                        | 
                                        v 
                                 +----->+ 
                                 |      | 
                                 | classifying 
                                 |      | 
                                 +------+ 
                                        | 
                             maintaining Flow Records 
                                        | 
                                        v 
    
    
                    Figure 1: Functions of the Metering Process 
    
Exporting Process 
    
   The Exporting Process sends Flow Records to one or more Collecting 
   Processes. The Flow Records are generated by one or more Metering 
   Processes. 
    
Collecting Process 
    
   The Collecting Process receives Flow Records from one or more 
   Exporting Processes. The Collecting Process might store received 
   Flow Records or further process them, but these actions are out of 
   the scope of this document. 
    
Export Packet 

   An Export Packet is a packet originating at the Exporting Process 
   that carries the Flow Records of this Exporting Process and whose 
   destination is the Collecting Process.  
    
Packet Header 

   The Packet Header is the first part of an Export Packet, which 
   provides basic information about the packet such as the IPFIX 
   version, number of records contained within the packet, sequence 
   numbering, etc. 
    
Template Record 



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   A Template Record defines the structure and interpretation of fields 
   in a Flow Data Record. 
    
Flow Data Record 
    
   A Flow Data Record is a data record that contains values of the Flow 
   parameters corresponding to a Template Record. In this document, the 
   Flow Data Record is also referred to as Flow Record. 
    
Options Template Record 
    
   An Options Template Record defines the structure and interpretation 
   of fields in an Options Data Record, including defining how to scope 
   the applicability of the Options Data Record. 
    
Options Data Record 
    
   The Options Data Record is a data record that contains values and 
   scope information of the Flow measurement parameters, corresponding 
   to an Options Template Record. 

FlowSet 

   FlowSet is a generic term for a collection of records that have a 
   similar structure. In an Export Packet, one or more FlowSets follow 
   the Packet Header. 
   There are three different types of FlowSets: Template FlowSet, 
   Options Template FlowSet, and Data FlowSet.   
    
Template FlowSet 

   A Template FlowSet is a collection of one or more Template Records 
   that have been grouped together in an Export Packet.   

Options Template FlowSet 

   An Options Template FlowSet is a collection of one or more Options 
   Template Records that have been grouped together in an Export 
   Packet. 
    
Data FlowSet 





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   A Data FlowSet is one or more records, of the same type, that are 
   grouped together in an Export Packet. Each record is either a Flow 
   Data Record or an Options Data Record previously defined by a 
   Template Record or an Options Template Record. 

 3.1 Terminology Summary Table 

         FlowSet        Template  Record        Data Record 
   +----------------------------------------------------------------+ 
   |                  |                    |  Flow Data Record(s)   | 
   | Data FlowSet     |          /         |          or            | 
   |                  |                    | Options Data Record(s) | 
   +----------------------------------------------------------------+ 
   | Template FlowSet | Template Record(s) |           /            | 
   +----------------------------------------------------------------+ 
   | Options Template | Options Template   |           /            | 
   | FlowSet          | Record(s)          |                        | 
   +----------------------------------------------------------------+ 
    
   A Data FlowSet is composed of an Options Data Record(s) or Flow Data 
   Record(s). No Template Record is included. A Template Record defines 
   the Flow Data Record, and an Options Template Record defines the 
   Options Data Record.  
    
   A Template FlowSet is composed of Template Record(s). No Flow or 
   Options Data Record is included. 
     
   An Options Template FlowSet is composed of Options Template 
   Record(s). No Flow or Options Data Record is included.  
    
 4. The Metering Process 
    
   The description of the Metering Process (for example, sampled or 
   not, aggregation or not), which is the way in which Flows are 
   created from the observed IP packets, is beyond the scope of this 
   document. Nevertheless, some aspects of the Metering Process have 
   some influences on the IPFIX protocol 
    
 4.1 Flow Expiration 
    
   A Flow is considered to be inactive if no packets belonging to the 
   Flow have been observed at the Observation Point for a given 




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   timeout. If any packet is seen within the timeout, the flow is 
   considered an active Flow. 
   A Flow can be exported under the following conditions: 
    
      1. If the Metering Process can detect the end of a Flow. For 
      example, if the FIN or RST bit is detected in a TCP [3] 
      connection, the Flow Record is exported. 
       
      2. If the Flow has been inactive for a certain period of time. 
      This inactivity timeout SHOULD be configurable at the Metering 
      Process, with a minimum value of 0 for an immediate expiration. 
       
      3. For long-lasting Flows, the Exporting Process SHOULD export 
      the Flow Records on a regular basis. This timeout SHOULD be 
      configurable at the Metering Process. 
       
      4. If the Metering Process experiences internal constraints, a 
      Flow MAY be forced to expire prematurely; for example, counters 
      wrapping or low memory. 
    
 5. Transport Protocol 
    
   The IPFIX Protocol Specifications have been designed to be transport 
   protocol independent. It can operate over congestion-aware protocols 
   such as TCP [3] or SCTP [RFC2960].    
    
   Note that the Exporter can export to multiple Collecting Processes, 
   using independent transport protocols. 
    
 5.1 TCP 
    
   To be completed. 
   TCP [3]  
    
 5.2 STCP 
    
   This section describes how IPFIX can be transported over SCTP 
   [RFC2960] using traditional reliable mode.  
    
   IPFIX can also be transported over the partial reliable or 
   unreliable mode [PR-SCTP]. These last 2 modes will be briefly 
   discussed, while waiting for [PR-SCTP] to become a standard. 




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 5.2.1   Congestion Avoidance 
    
   The SCTP transport protocol provides the required level of 
   congestion avoidance by design. 

 5.2.2    Reliability 
    
   The SCTP transport protocol is by default reliable, but has the 
   capability to operate in unreliable and partially reliable modes 
   [PR-SCTP]. 
    
   Using reliable SCTP streams for the IPFIX export is not in itself a 
   guarantee that all records are delivered. If there is congestion on 
   the link from the exporter to the collector, or if a significant 
   amount of retransmissions are needed, the send queues on the 
   Exporting Process may fill up. In that case it's up to the Exporting 
   Process to decide what to do. It may either halt export (buffer the 
   data until there is space in the send queues again) or just throw 
   Export Packets away instead of inserting them into the send queue. 
   If any data is not inserted into the send queues, the sequence 
   numbers used for export must reflect the loss of data. 

 5.2.3    Exporting Process 

 5.2.3.1 MTU size 
    
   Each IPFIX Export Packet should be equal to or less than the local 
   MTU in size. When an IPFIX Export Packet is transmitted over a 
   network with an MTU smaller than the local MTU, IP fragmentation may 
   be used. 

 5.2.3.2 Source ID 
    
   The Export Packet must contain a Packet Header, which includes a 
   source id (SID). The SID indicates from which Observation Domain the 
   data is being exported, and should be kept unique for each such 
   domain. 
    
   If a Metering Process consists of a single Observation Domain, a 
   single SID value must be used for all Export Packets. The Exporting 
   Process will typically open one association to the collector, but 
   more are possible, in which one or more streams can be used. The 



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   Exporting Process has the choice of transmitting parts of the export 
   data in separate streams or all data in one stream. 
    
   If a Metering Process consists of multiple Observation Domains, one 
   SID value for each Observation Domain must be used. The Exporting 
   Process will typically open one association, but more are possible, 
   in which at least one stream per Observation Domain is used. 
    
   The Exporting Process has the choice of using more than one stream 
   per Observation Domain, but data from multiple Observation Domains 
   should not be transmitted over the same stream. 

 5.2.3.3 Association 
    
   The Exporting Process may create one or more associations 
   (connection "bundle" in SCTP terminology) to the Collecting Process. 
   The Collecting Process may not initiate the connection. Inside each 
   association one or more streams may be requested by the Exporting 
   Process. If the Collecting Process can not support the requested 
   number of streams, it may choose to refuse the connection and the 
   Exporting Process should try to reduce, if possible, the number of 
   streams needed to perform the export. 

 5.2.3.4 Template 
    
   An Observation Domain must use at least one stream, but may use 
   multiple streams, to export data records. The Observation Domain 
   must use the same SID value for all streams used. 
    
   An Exporting Process must not transmit packets with different SID 
   values in one stream, the Collecting Process should however verify 
   that the SID values are the expected values. 

 5.2.3.5 Template 
    
   Since the SCTP association is connection oriented the available 
   Template Records must be transmitted from each Observation Domain to 
   the Collecting Process immediately after the association is 
   established. 
    
   As a minimum the Template Records must be transmitted immediately 
   after they start to exist on the Metering Process and should 



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   preferably be transmitted before any data, using the new Template 
   Record, have been transmitted. The Collecting Process should however 
   accept data without a Template Record. 
     
   When using a reliable mode for Template Record export, or if the 
   exporter knows that the Export Packet containing the templates was 
   positively acknowledged by the SCTP layer, it is not necessary to 
   periodically export the Template Records. 

 5.2.4    Collecting Process  
    
   The Collecting Process should listen for a new association request 
   from the Exporting Process. The Collecting Process will request a 
   number of streams to use for export. If the Collecting Process 
   doesn't support the number of streams inside the association, the 
   Collecting Process must refuse the connection and continue listen 
   for a new request.  
    
   When data is received from an association, the Collecting Process 
   must correlate data, with the same SID value, from multiple streams 
   into one export Flow from an Observation Domain. This allows the 
   Observation Domain to use separate streams for different types of 
   information. 
    
   The Collecting Process should verify that the received Export 
   Packets inside one stream does not have diverting SID values. The 
   Exporting Process must not export packets inside one stream with 
   multiple SID values. The correlated Flow Records are then treated 
   like a normal export Flow. 

 5.2.5    SCTP Partially Reliable 
    
   This mode will not be discussed any further until [PR-SCTP] becomes 
   a standard, even if this mode offers a few advantages: 
   freedom to use SCTP as a reliable, single stream transport, as well 
   as multiple streams with different properties, for example in terms 
   of reliability, carrying different data types dependant on their 
   importance for the system. 
   Unreliable or partial reliability may be chosen for one or more 
   streams inside an association. Unreliable transport may be preferred 
   where large amount of data is to be exported and keeping send queues 
   is either an unnecessary overhead or impractical. Partial 
   reliability may be chosen where a small amount of queuing is 


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   possible. 
    
   Naturally it is better to send templates over a reliable stream and 
   send the data on an unreliable (or partial reliable) stream. When an 
   exporter handles data with different properties it might even be 
   preferable to send them over different streams according to those 
   properties. 
    
   Example: an Exporting Process can use two streams per Observation 
   Domain. A reliable stream could be used for exporting templates, to 
   reduce the likelihood of loss and to remove the need for blind 
   retransmissions, and a partial or unreliable stream for data, to 
   avoid buffering of large amounts of data. 

 6. Failover 
    
   When to fail over? 
   How to fail back?  
   How to ensure stability of the failover mechanism (prevent 
   oscillations)? 
   Does the exporter open connections to all the potential collectors 
   and keep them primed with template info? 
    
 6.1 Simple Failover based on the transport protocol 
    
   In case the transport protocol is connection oriented. 
   So in case of TCP [3] or SCTP [RFC2960]. 
   To be completed. 
    
 6.2 Something else? 
    
   Potentially based on some application level ACK from the exporter? 
    
 7. Packet Layout 
    
   An Export Packet consists of a Packet Header followed by one or more 
   FlowSets. The FlowSets can be any of the possible three types: 
   Template, Data, or Options Template.  
    
   Export Packet: 
   +--------+-------------------------------------------+ 
   |        | +----------+ +---------+ +----------+     | 
   | Packet | | Template | | Data    | | Options  |     | 



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   | Header | | FlowSet  | | FlowSet | | Template | ... | 
   |        | |          | |         | | FlowSet  |     | 
   |        | +----------+ +---------+ +----------+     | 
   +--------+-------------------------------------------+ 

   A FlowSet ID is used to distinguish the different types of FlowSets. 
   FlowSet IDs lower than 256 are reserved for special FlowSets, such 
   as the Template FlowSet (ID 0) and the Options Template FlowSet (ID 
   1). The Data FlowSets have a FlowSet ID greater than 255. 

   The format of the Template, Data, and Options Template FlowSets will 
   be discussed later in this document. The Exporter MUST code all 
   fields of the different FlowSets in network byte order (big-endian). 
    
   Following are some examples of export packets: 
    
   1. An Export Packet consisting of interleaved Template, Data, and 
   Options Template FlowSets-A newly created Template is exported as 
   soon as possible. So if there is already an Export Packet with a 
   Data FlowSet that is being prepared for export, the Template and 
   Option FlowSets are also interleaved with this information, subject 
   to availability of space. 
    
   Export Packet: 
   +--------+--------------------------------------------------------+ 
   |        | +----------+ +---------+     +-----------+ +---------+ | 
   | Packet | | Template | | Data    |     | Options   | | Data    | | 
   | Header | | FlowSet  | | FlowSet | ... | Template  | | FlowSet | | 
   |        | |          | |         |     | FlowSet   | |         | | 
   |        | +----------+ +---------+     +-----------+ +---------+ | 
   +--------+--------------------------------------------------------+  
    
   2. An Export Packet consisting entirely of Data FlowSets-After the 
   appropriate Template Records have been defined and transmitted to 
   the NetFlow Collector device, the majority of Export Packets 
   consists solely of Data FlowSets.  
    
   Export Packet: 
   +--------+----------------------------------------------+ 
   |        | +---------+     +---------+      +---------+ | 
   | Packet | | Data    | ... | Data    | ...  | Data    | | 
   | Header | | FlowSet | ... | FlowSet | ...  | FlowSet | | 
   |        | +---------+     +---------+      +---------+ | 


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   +--------+----------------------------------------------+   

   3. An Export Packet consisting entirely of Template and Options 
   Template FlowSets-The Exporter MAY transmit a packet containing 
   Template and Options Template FlowSets periodically to help ensure 
   that the NetFlow Collector has the correct Template Records and 
   Options Template Records when the corresponding Flow Data records 
   are received.  
    
   Export Packet: 
   +--------+-------------------------------------------------+ 
   |        | +----------+     +----------+      +----------+ | 
   | Packet | | Template |     | Template |      | Options  | | 
   | Header | | FlowSet  | ... | FlowSet  | ...  | Template | | 
   |        | |          |     |          |      | FlowSet  | | 
   |        | +----------+     +----------+      +----------+ | 
   +--------+-------------------------------------------------+ 
    
 8. Export Packet Format 
    
 8.1 Header Format 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Version Number          |            Count              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           sysUpTime                           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           UNIX Secs                           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                       Sequence Number                         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                        Source ID                              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   Packet Header Field Descriptions  
    
   Version 
           Version of Flow Record format exported in this packet. The 
           value of this field is 0x0009 for the current version. 
    
   Count 



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           The total number of records in the Export Packet, which is 
           the sum of Options FlowSet records, Template FlowSet 
           records, and Data FlowSet records. 
    
   SysUpTime 
           Time in milliseconds since this device was first booted. 
           Refer to [1]. 
    
   UNIX Secs 
           Seconds since 0000 UTC 1970. 
            
   Sequence Number 
           Incremental sequence counter of all Export Packets sent from 
           the current Observation Domain by the Exporting Process. 
           This value MUST be cumulative, and SHOULD be used by the 
           Collector to identify whether any Export Packets have been 
           missed. 

   Source ID 
           A 32-bit value that identifies the Exporter Process 
           Observation Domain. Collecting Process SHOULD use the 
           combination of the source IP address and the Source ID field 
           to separate different export streams originating from the 
           same Exporting Process. 
            
 8.2 Template FlowSet Format 
    
   One of the essential elements in the IPFIX format is the Template 
   FlowSet. Templates greatly enhance the flexibility of the Flow 
   Record format because they allow the Collecting Process to process 
   Flow Records without necessarily knowing the interpretation of all 
   the data in the Flow Record.   
    
   The format of the Template FlowSet is as follows: 

    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       FlowSet ID = 0          |          Length               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Template ID 1           |         Field Count           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Field Type 1           |         Field Length 1        | 


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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Field Type 2           |         Field Length 2        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |             ...               |              ...              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Field Type N           |         Field Length N        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Template ID 2           |         Field Count           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Field Type 1           |         Field Length 1        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Field Type 2           |         Field Length 2        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |             ...               |              ...              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Field Type M           |         Field Length M        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |             ...               |              ...              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Template ID K          |         Field Count           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |             ...               |              ...              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   Template FlowSet Field Descriptions  
    
   FlowSet ID 
           FlowSet ID value of 0 is reserved for the Template FlowSet. 
    
   Length 
           Total length of this FlowSet. Because an individual Template 
           FlowSet MAY contain multiple Template Records, the Length 
           value MUST be used to determine the position of the next 
           FlowSet record, which could be any type of FlowSet. Length 
           is the sum of the lengths of the FlowSet ID, the Length 
           itself, and all Template Records within this FlowSet. 
            
   Template ID 
           Each of the newly generated Template Records is given a 
           unique Template ID. This uniqueness is local to the 
           Observation Domain that generated the Template ID.      
           Template IDs 0-255 are reserved for Template FlowSets, 
           Options FlowSets, and other reserved FlowSets yet to be 


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           created. Template IDs of Data FlowSets are numbered from 256 
           to 65535. 
    
   Field Count 
           Number of fields in this Template Record. Because a Template 
           FlowSet usually contains multiple Template Records, this 
           field allows the Collecting Process to determine the end of 
           the current Template Record and the start of the next. 
 
   Field Type 
           A numeric value that represents the type of the field. Refer 
           to the "Field Type Definitions" section.        

   Field Length 
           The length of the corresponding Field Type, in bytes. Refer 
           to the "Field Type Definitions" section.       

 8.3 Data FlowSet Format 
    
   The format of the Data FlowSet is as follows: 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |    FlowSet ID = Template ID   |          Length               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 1 - Field Value 1    |   Record 1 - Field Value 2    | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 1 - Field Value 3    |             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 2 - Field Value 1    |   Record 2 - Field Value 2    | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 2 - Field Value 3    |             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 3 - Field Value 1    |             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |              ...              |            Padding            | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   
    
   Data FlowSet Field Descriptions  
    
   FlowSet ID = Template ID 



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           Each Data FlowSet is associated with a FlowSet ID. The 
           FlowSet ID maps to a (previously generated) Template ID. The 
           Collecting Process MUST use the FlowSet ID to find the 
           corresponding Template Record and decode the Flow Records 
           from the FlowSet. 
    
   Length 
           The length of this FlowSet.  
           Length is the sum total of lengths of FlowSet ID, Length 
           itself, all Flow Records within this FlowSet, and the 
           padding bytes, if any.       
    
   Record N - Field Value M 
           The remainder of the Data FlowSet is a collection of Flow 
           Data Record(s), each containing a set of field types and 
           values. The Type and Length of the fields have been 
           previously defined in the Template Record referenced by the 
           FlowSet ID or Template ID. 
    
   Padding 
           The Exporting Process SHOULD insert some padding bytes so 
           that the subsequent FlowSet starts at a 4-byte aligned 
           boundary. It is important to note that the Length field 
           includes the padding bits. 
    
   Interpretation of the Data FlowSet format can be done only if the 
   Template FlowSet corresponding to the Template ID is available at 
   the Collecting Process.    

 9. Options 
    
 9.1 Options Template FlowSet Format 
    
   The Options Template Record (and its corresponding Options Data 
   Record) is used to supply information about the Metering Process 
   configuration or Metering Process specific data, rather than 
   supplying information about IP Flows. 
   For example, the Options Template FlowSet can report the sample rate 
   of a specific interface, if sampling is supported, along with the 
   sampling method used. 
    
   The format of the Options Template FlowSet follows. 
    



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    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       FlowSet ID = 1          |          Length               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |         Template ID           |      Option Scope Length      | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |        Option Length          |       Scope 1 Field Type      | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     Scope 1 Field Length      |               ...             | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     Scope N Field Length      |      Option 1 Field Type      | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     Option 1 Field Length     |             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     Option M Field Length     |           Padding             | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   Options Template FlowSet Field Definitions   
    
   FlowSet ID = 1 
           A FlowSet ID value of 1 is reserved for the Options 
           Template. 
    
   Length 
           Total length of this FlowSet. Each Options Template FlowSet 
           MAY contain multiple Options Template Records. Thus, the 
           Length value MUST be used to determine the position of the 
           next FlowSet record, which could be either a Template 
           FlowSet or Data FlowSet.                
           Length is the sum total of lengths of FlowSet ID, the Length 
           itself, and all Options Template Records within this FlowSet 
           Template ID. 
    
   Template ID 
           Template ID of this Options Template. This value is greater 
           than 255. 
     
   Option Scope Length 
           The length in bytes of any Scope fields definition contained 
           in the Options Template Record (The use of "Scope" is 
           described below).  
    


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   Option Length 
           The length (in bytes) of any options field definitions 
           contained in this Options Template Record. 
    
   Scope 1 Field Type 
           The relevant portion of the Exporting Process/Metering 
           Process to which the Options Template Record refers. 
           Currently defined values are:  
               1 System   
               2 Interface  
               3 Line Card  
               4 Cache  
               5 Template         
           For example, the Metering Process can be implemented on a 
           per-interface basis, so if the Options Template Record were 
           reporting on how the NetFlow process is configured, the 
           Scope for the report would be 2 (interface). The associated 
           interface ID would then be carried in the associated Options 
           Data FlowSet. The Scope can be limited further by listing 
           multiple scopes that all must match at the same time. Note 
           that the Scope fields always precede the Option fields. 
            
    
   Scope 1 Field Length 
           The length (in bytes) of the Scope field, as it would appear 
           in an Options Data Record. 
    
   Option 1 Field Type 
           A numeric value that represents the type of field that would 
           appear in the Options Template Record. Refer to the Field 
           Type Definitions section. 
    
   Option 1 Field Length 
           The length (in bytes) of the Option Field. 
    
   Padding 
           The Exporting Process SHOULD insert some padding bytes so 
           that the subsequent FlowSet starts at a 4-byte aligned 
           boundary. It is important to note that the Length field 
           includes the padding bits. 
    
 9.2 Options Data Record Format 
    


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   The Options Data Records are sent in Data FlowSets, on a regular 
   basis, but not with every Flow Data Record. How frequently these 
   Options Data Records are exported is configurable. See the Templates 
   Management" section for more details. 
    
   The format of the Data FlowSet containing Options Data Records 
   follows. 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |    FlowSet ID = Template ID   |          Length               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 1 - Scope 1 Value    |Record 1 - Option Field 1 Value| 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |Record 1 - Option Field 2 Value|             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 2 - Scope 1 Value    |Record 2 - Option Field 1 Value| 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |Record 2 - Option Field 2 Value|             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Record 3 - Scope 1 Value    |Record 3 - Option Field 1 Value| 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |Record 3 - Option Field 2 Value|             ...               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |              ...              |            Padding            | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   Options Data Records of the Data FlowSet Field Descriptions  
    
   FlowSet ID = Template ID 
           A FlowSet ID precedes each group of Options Data Records 
           within a Data FlowSet. The FlowSet ID maps to a previously 
           generated Template ID corresponding to this Options Template 
           Record. The Collecting Process MUST use the FlowSet ID to 
           map the appropriate type and length to any field values that 
           follow. 
    
   Length 
           The length of this FlowSet.   
           Length is the sum of the lengths of the FlowSet ID, Length 
           itself, all the Options Data Records within this FlowSet, 
           and the padding bytes, if any. 


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   Record N - Option Field M Value 
           The remainder of the Data FlowSet is a collection of Flow 
           Records, each containing a set of scope and field values. 
           The type and length of the fields were previously defined in 
           the Options Template Record referenced by the FlowSet ID or 
           Template ID. 
    
   Padding 
           The Exporting Process SHOULD insert some padding bytes so 
           that the subsequent FlowSet starts at a 4-byte aligned 
           boundary. It is important to note that the Length field 
           includes the padding bits. 
    
   The Data FlowSet format can be interpreted only if the Options 
   Template FlowSet corresponding to the Template ID is available at 
   the Collecting Process. 
    
 10. Variable Length Data Type 

   Note: this section reflects the mailing list ideas but the wording 
   should be worked on.  
    
   In the Template Flowset (template definition), let's put FFFF for 
   the length of the variable length data types.  Then, the actual 
   length is encoded in data Flowset (Flow Records) as follows:  
   - if length is < 255 bytes, the length is stored in 1 byte  
   - if length is >=255 bytes, 255 is stored in the first byte, and the  
   actual 16 bits length is stored in the next 2 bytes.  
    
   The cases of length of >= 255 will be very rear. And even in these 
   cases, one extra byte will represent <= 1/255-th part of data 
   record.  
    
   Why FFFF and not 0?  
   The reason for this is that FFFF is a truly invalid value which  
   should be caught in collectors, by good implementations, today. For 
   0 this isn't necessary the case as it's meaning is "just" pointless, 
   but not a course of concern for the collectors.  
   Basically FFFF should make the Collecting Process (current 
   implementations) discard the template as being invalid.  
   Note also that some option templates data types could potentially 
   have a length of 0.  


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   So the advantages of this proposal are:  
   - code the length on 1 byte for most of the cases;  in that case, we 
   use the 8 bits to code the length, so with a max of 254 bytes  
    (because 255 is reserved)  
   - if the length is above 254, we use 3 bytes, the last 2 bytes could 
   transport a length of max 64 k - 7 bytes (in the Data FlowSet, 2 for 
   the FlowSet ID + 2 for the FlowSet Length + 1 byte for "0xff" + 2 
   for the variable length)  
    
 11. Template Management 

   Flow Data records that correspond to a Template Record MAY appear in 
   the same and/or subsequent Export Packets. The Template Record is 
   not necessarily carried in every Export Packet. As such, the 
   Collecting Process MUST store the Template Record to interpret the 
   corresponding Flow Data Records that are received in subsequent data 
   packets. 
    
   A Collecting Process that receives Export Packets from several 
   Observation Domains from the same Exporter MUST be aware that the 
   uniqueness of the Template ID is not guaranteed across Observation 
   Domains. 
    
   The Template IDs must remain constant for the life of the Metering 
   Process and the Exporting Process. If the Exporting Process or the 
   Metering Process restarts for any reason, all information about 
   Templates will be lost and new Template IDs will be created. 
   Template IDs are thus not guaranteed to be consistent across an 
   Exporting Process or Metering Process restart. 

   A newly created Template record is assigned an unused Template ID 
   from the Exporter. If the template configuration is changed, the 
   current Template ID is abandoned and SHOULD NOT be reused until the 
   Metering Process. If a Collecting Process should receive a new 
   definition for an already existing Template ID, it MUST discard the 
   previous template definition and use the new one. 

   If a configured Template Record on the Exporting Process is deleted, 
   and re-configured with exactly the same parameters, the same 
   Template ID COULD be reused. 




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   The Exporting Process sends the Template FlowSet and Options 
   Template FlowSet under the following conditions: 
     
    1. After a NetFlow process restarts, the Exporting Process MUST NOT 
       send any Data FlowSet without sending the corresponding Template 
       FlowSet and the required Options Template FlowSet in a previous 
       packet or including it in the same Export Packet. It MAY 
       transmit the Template FlowSet and Options Template FlowSet, 
       without any Data FlowSets, in advance to help ensure that the 
       Collector will have the correct Template Record before receiving 
       the first Flow or Options Data Record. 

    2. In the event of configuration changes, the Exporting Process 
       SHOULD send the new template definitions at an accelerated rate. 
       In such a case, it MAY transmit the changed Template Record(s) 
       and Options Template Record(s), without any data, in advance to 
       help ensure that the Collector will have the correct template 
       information before receiving the first data. 

    3. On a regular basis, the Exporting Process MUST send all the 
       Template Records and Options Template Records to refresh the 
       Collecting Process. Template IDs have a limited lifetime at the 
       Collecting Process and MUST be periodically refreshed. 
       Two approaches are taken to make sure that Templates get 
       refreshed at the Collecting Process: 
          * Every N number of Export Packets. 
          * On a time basis, so every N number of minutes. 
       Both options MUST be configurable by the user on the Exporting 
       Porcess. 
       When one of these expiry conditions is met, the Exporting 
       Process MUST send the Template FlowSet and Options Template.  
    
 12. The Collecting Process's Side 
    
   The Collecting Process receives Template Records from the Exporting 
   Process, normally before receiving Flow Data Records (or Options 
   Data Records). The Flow Data Records (or Options Data Records) can 
   then be decoded and stored locally on the devices. If the Template 
   Records have not been received at the time Flow Data Records (or 
   Options Data Records) are received, the Collecting Process SHOULD 
   store the Flow Data Records (or Options Data Records) and decode 
   them after the Template Records are received. A Collecting Process 
   device MUST NOT assume that the Data FlowSet and the associated 


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   Template FlowSet (or Options Template FlowSet) are exported in the 
   same Export Packet. 
    
   The Collecting Process MUST NOT assume that one and only one 
   Template FlowSet is present in an Export Packet.  
    
   The life of a template at the Collecting Process is limited to a 
   fixed refresh timeout. Templates not refreshed from the Exporting 
   Process within the timeout are expired at the Collecting Process. 
   The Collecting Process MUST NOT attempt to decode the Flow or 
   Options Data Records with an expired Template. At any given time the 
   Collecting Process SHOULD maintain the following for all the current 
   Template Records and Options Template Records: <Exporting Process, 
   Observation Domain, Template ID, Template Definition, Last Received> 
   Note that the Observation Domain is identified by the Source ID 
   field from the Export Packet. 
    
   Template IDs are unique per Exporting Process and per Observation 
   Domain.  
    
   If the Collecting Process receives a new Template Record (for 
   example, in the case of an Exporter restart) it MUST immediately 
   override the existing Template Record. 
    
   Finally, note that the Collector MUST accept padding in the Data 
   FlowSet and Options Template FlowSet, which means for the Flow Data 
   Records, the Options Data Records and the Template Records. 
   Refer to the terminology summary table in Section 3.1. 
    
 13. Examples 
    
   Let's consider the example of an Export Packet composed of a  
   Template FlowSet, a Data FlowSet (which contains three Flow Data 
   Records), an Options Template FlowSet and a Data FlowSet (which 
   contains 2 Options Data Records).  
    
   Export Packet: 
   +--------+---------------------------------------------. . . 
   |        | +--------------+ +-----------------------+  
   | Packet | | Template     | | Data                  |  
   | Header | | FlowSet      | | FlowSet               |   . . . 
   |        | | (1 Template) | | (3 Flow Data Records) |  
   |        | +--------------+ +-----------------------+  


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   +--------+---------------------------------------------. . . 

       . . .+-------------------------------------------------+ 
            +------------------+ +--------------------------+ | 
            | Options          | | Data                     | | 
       . . .| Template FlowSet | | FlowSet                  | | 
            | (1 Template)     | | (2 Options Data Records) | | 
            +------------------+ +--------------------------+ | 
       . . .--------------------------------------------------+ 
    
 13.1 Packet Header Example 
    
   The Packet Header is composed of: 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     Version = 0x0009          |          Count = 7            | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           sysUpTime                           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           UNIX Secs                           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                       Sequence Number                         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           Source ID                           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
 13.2 Template FlowSet Example 
    
   We want to report the following Field Types: 
   - The source IP address (IPv4), so the length is 4 
   - The destination IP address (IPv4), so the length is 4 
   - The next-hop IP address (IPv4), so the length is 4 
   - The number of bytes of the Flow 
   - The number of packets of the Flow 
    
   Therefore, the Template FlowSet will be composed of the following: 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       FlowSet ID = 0          |      Length = 28 bytes        | 



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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Template ID 256         |       Field Count = 5         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     IP_SRC_ADDR = 0x0008      |       Field Length = 4        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     IP_DST_ADDR = 0x000C      |       Field Length = 4        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |     IP_NEXT_HOP = 0x000F      |       Field Length = 4        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       IN_PKTS = 0x0002        |       Field Length = 4        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       IN_BYTES = 0x0001       |       Field Length = 4        | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
 13.3 Data FlowSet Example 

   In this example, we report the following three Flow records: 
    
   Src IP addr. | Dst IP addr. | Next Hop addr. | Packet | Bytes  
                |              |                | Number | Number 
   --------------------------------------------------------------- 
   198.168.1.12 | 10.5.12.254  | 192.168.1.1    | 5009   | 5344385 
   192.168.1.27 | 10.5.12.23   | 192.168.1.1    | 748    | 388934 
   192.168.1.56 | 10.5.12.65   | 192.168.1.1    | 5      | 6534 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       FlowSet ID = 256        |          Length = 64          | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                          198.168.1.12                         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                          10.5.12.254                          | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                          192.168.1.1                          | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                             5009                              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                            5344385                            |  
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                          192.168.1.27                         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           10.5.12.23                          |  


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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                          192.168.1.1                          | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                              748                              | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                             388934                            | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                          192.168.1.56                         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           10.5.12.65                          | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                           192.168.1.1                         | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                               5                               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |                              6534                             | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
   Note that padding was not necessary in this example. 
    
 13.4 Options Template FlowSet Example 
    
   Per line card (the router being composed of two line cards), we want 
   to report the following Field Types: 
   - Total number of Export Packets 
   - Total number of exported Flows  
    
   The format of the Options Template FlowSet is as follows: 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       FlowSet ID = 1          |          Length = 24          | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Template ID 257         |    Option Scope Length = 4    | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Option Length = 8       |  Scope 1 Field Type = 0x0003  | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |   Scope 1 Field Length = 2    |   TOTAL_EXP_PKTS_SENT = 41    | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Field Length = 4        |     TOTAL_FLOWS_EXP = 42      | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |       Field Length = 4        |           Padding             | 


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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
 13.5 Data FlowSet with Options Data Records Example 
    
   In this example, we report the following two records: 
    
   Line Card ID | Export Packet| Export Flow  
   ------------------------------------------ 
   Line Card 1  | 345          | 10201     
   Line Card 2  | 690          | 20402 
    
    0                   1                   2                   3 
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |    FlowSet ID = 257           |         Length = 14           | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |             1                 |             345               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |           10201               |              2                | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |             2                 |             690               | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
   |           20402               |           Padding             | 
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
    
 14. References 
    
   [1]  R. Presuhn et al, "Management Information Base (MIB) for the 
   Simple Network Management Protocol (SNMP)" RFC 3418, December 2002 
    
   [2]  J. Postel, "User Datagram Protocol" RFC 768, August 1980 
    
   [3]  "TRANSMISSION CONTROL PROTOCOL DARPA INTERNET PROGRAM PROTOCOL 
   SPECIFICATION" RFC 793, September 1981 
    
   [IPFIX-REQ] J. Quittek, T. Zseby, B. Claise, S. Zander, 
   "Requirements for IP Flow Information Export" draft-ietf-ipfix-reqs-
   10.txt, June 2003 
    
   [IPFIX-ARCH] Sadasivan, G, Brownlee, N. "Architecture Model for IP 
   Flow Information Export" draft-ietf-ipfix-arch-01.txt", June 2003 
    




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   [IPFIX-INFO] Calato, P, Meyer, J, Quittek, J, "Information Model for 
   IP Flow Information Export" draft-ietf-ipfix-info-01, August 2003 

   [IPFIX-PROTO] Claise, B, Fullmer, M, Calato, P, Penno, R, "IPFIX 
   Protocol Specifications", draft-ietf-ipfix-protocol-00.txt, June 
   2003   
    
   [RFC2960] Stewart, R. (ed.) "Stream Control Transmission Protocol", 
   RFC 2960, October 2000  
    
   [PR-SCTP] Stewart, R, "SCTP Partial Reliability Extension", draft-
   stewart-tsvwg-prsctp-04.txt 
    
   [NETFLOW9] Claise, B, et al "Cisco Systems NetFlow Services Export 
   Version 9", draft-claise-netflow-9-06.txt, October 2003   

5. Acknowledgments 
    
   To be completed. 
    
uthors Addresses 

   Benoit Claise 
   Cisco Systems 
   De Kleetlaan 6a b1 
   1831 Diegem 
   Belgium 
   Phone: +32 2 704 5622 
   E-mail: bclaise@cisco.com 
    
   Mark Fullmer 
   OARnet 
   2455 North Star Rd. 
   Columbus, Ohio 43221 
   Phone: +1 (614) 728-8100 
   Email: maf@eng.oar.net 
    
   Reinaldo Penno 
   Nortel Networks 
   2305 Mission College Blvd 
   Santa Clara, CA 95054 
   Phone: +1 408.565.3023 
   Email: rpenno@nortelnetworks.com 



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   Paul Calato  
   Riverstone Networks, Inc.  
   5200 Great America Parkway  
   Santa Clara, CA 95054  USA  
   Phone:  +1 (603) 557-6913  
   Email: calato@riverstonenet.com 











































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PAFTECH AB 2003-20262026-04-23 08:36:29