rfc1329.txt

RFC 的详细文档！


RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


   by Provider:
    TIMER_response(Timer_id  : timer_name_type;
                   subscript : integer);


10.3. The Module Header and Interaction Points

   module LS_module systemprocess;
    ip LS_ARPSAP     : SAPchn(Provider);
       LS_IPSAP      : SAPchn(Provider);
       SNAP1_ARPSAP  : SAPchn(User);
       SNAP1_LSSAP   : SAPchn(User);
       SNAP1_IPSAP   : SAPchn(User);
       SNAP2_ARPSAP  : SAPchn(User);
       SNAP2_LSSAP   : SAPchn(User);
       SNAP2_IPSAP   : SAPchn(User);
       LS_System_Access_Point : System_Access_Point_chn(User);
   end;

10.4. The Modulebody of the Load Sharing Entity

   body LS_body for LS_module;

   module multiplexer_module process;
    ip LS_IPSAP    : SAPchn(Provider);
       SNAP1_IPSAP : SAPchn(User);
       SNAP2_IPSAP : SAPchn(User);
   end;

   module cache_administration_module process;
    ip LS_ARPSAP    : SAPchn(Provider);
       SNAP1_ARPSAP : SAPchn(User);
       SNAP1_LSSAP  : SAPchn(User);
       SNAP2_ARPSAP : SAPchn(User);
       SNAP2_LSSAP  : SAPchn(User);
       LS_System_Access_Point : System_Access_Point_chn(User);
   end;

   body cache_administration_body for cache_administration_module;
     (* defined later *)
   end;

   body multiplexer_body for multiplexer_module;
     (* defined later *)
   end;

   modvar
    cache_administration : cache_administration_module;



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RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


    multiplexer          : multiplexer_module;

   initialize
   begin
    ethernet         := 1;
    ip               := 2048;
    fddi_addr_length := 6;
    ip_addr_length   := 4;
    init cache_administration      with cache_administration_body;
    init multiplexer               with multiplexer_body;
    attach LS_IPSAP                to multiplexer.LS_IPSAP;
    attach SNAP1_IPSAP             to multiplexer.SNAP1_IPSAP;
    attach SNAP2_IPSAP             to multiplexer.SNAP2_IPSAP;
    attach LS_ARPSAP               to cache_administration.LS_ARPSAP;
    attach SNAP1_ARPSAP            to cache_administration.SNAP1_ARPSAP;
    attach SNAP1_LSSAP             to cache_administration.SNAP1_LSSAP;
    attach SNAP2_ARPSAP            to cache_administration.SNAP2_ARPSAP;
    attach SNAP2_LSSAP             to cache_administration.SNAP2_LSSAP;
    attach LS_System_Access_Point  to cache_administration.
                                       LS_System_Access_Point;
   end; end;

10.5. The Modulebody for the Multiplexer

body multiplexer_body for multiplexer_module;

type
  Type_of_addr_type = (individual, multi, broad);
  ring_type         = (primary, secondary);

var
  act_S_MAC_addr : HW_addr_type;

function determ_addrtype(HW_addr: HW_addr_type): Type_of_addr_type;
primitive;
(*
  Returns the type of a hardware address.
  (Individual, multicast or broadcast address)
*)

function get_cacheentry(prtype: integer; P_MAC_addr: HW_addr_type;
 var S_MAC_addr : HW_addr_type): boolean;
primitive;
(*
 Returns the associated secondary MAC address for a given primary MAC
 address and protocol type. If an entry exists, the value TRUE is
 returned.
*)



Kuehn                                                          [Page 16]

RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


function ls_criteria : ring_type;
(*
 Returns the ring on which the actual frame should be transmitted.
*)
primitive;

trans

when LS_IPSAP.UNITDATA_request(Source_addr,Dest_addr,QoS,PDU) begin
 if determ_addrtype(Dest_addr) <> individual then
 output SNAP1_IPSAP.UNITDATA_request(Source_addr,Dest_addr,QoS,PDU);
 else begin
  if get_cacheentry(ip,Dest_addr,act_S_MAC_addr) and
   (ls_criteria=secondary) then
  output SNAP2_IPSAP.UNITDATA_request(My_S_MAC_addr,
   act_S_MAC_addr,QoS,PDU);
  else
  output SNAP1_IPSAP.UNITDATA_request(Source_addr,Dest_addr,QoS,PDU);
 end;
end;

when SNAP1_IPSAP.UNITDATA_indication(Source_addr,Dest_addr,QoS,PDU)
begin
 output LS_IPSAP.UNITDATA_indication(Source_addr,Dest_addr,QoS,PDU);
end;

when SNAP2_IPSAP.UNITDATA_indication(Source_addr,Dest_addr,QoS,PDU)
begin
 if determ_addrtype(Dest_addr) = individual then begin
  Dest_addr := My_P_MAC_addr;
  output LS_IPSAP.UNITDATA_indication(Source_addr,Dest_addr,QoS,PDU);
 end;
end;

10.6. The Modulebody for the Cache Administration

body cache_administration_body for cache_administration_module;

type
 arp_pdu_type = record
  hwtype        : integer;
  prtype        : integer;
  HW_length     : integer;
  PR_length     : integer;
  operation     : (request,reply);
  HW_sender     : HW_addr_type;
  PR_sender     : PR_addr_type;
  HW_receiver   : HW_addr_type;



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RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


  PR_receiver   : PR_addr_type;
 end;

 dmarp_operation_type = (request,reply,error,search,found,query,hold);

 dmarp_pdu_type = record
  hwtype        : integer;
  prtype        : integer;
  HW_length     : integer;
  PR_length     : integer;
  operation     : dmarpoperation_type;
  HW_1          : HW_addr_type;
  HW_2          : HW_addr_type;
  PR_sender     : PR_addr_type;
  PR_receiver   : PR_addr_type;
 end;

var
 arp_pdu        : arp_pdu_type;
 dmarp_pdu      : dmarp_pdu_type;
 send_pdu       : dmarp_pdu_type;
 act_P_MAC_addr : HW_addr_type;

function my_pr_address(prtype : integer ; praddr : PR_addr_type):
boolean;
(*
 Returns TRUE, if praddr is my station address, the protocol type is
 prtype. (2048d for the Internet protocol)
*)
primitive;

function get_my_pr_addr(prtype : integer) : PR_addr_type;
(*
 Returns my station address, the protocol has the number prtype.
*)

function extract_arp_pdu(PDU : PDU_type) : arp_pdu_type;
(*
 Returns the data contained in an ARP PDU as a record.
*)
primitive;

function extract_dmarp_pdu(PDU : PDU_type) : dmarp_pdu_type;
(*
 Returns the data contained in an DMARP PDU as a record.
*)
primitive;




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RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


function assemble_dmarp_pdu(dmarp_pdu : dmarp_pdu_type): PDU;
(*
 Returns a DMARP PDU from the data in the record.
*)
primitive;

procedure create_entry(prtype: integer; P_MAC_addr: HW_addr_type;
 S_MAC_addr: HW_addr_type; LS_Bit: flag; OR_Bit: flag;
 H_Bit: flag; Q_Bit: flag; R_Bit: flag; V_Bit: flag);
(*
 Creates a new entry in the address cache, if no entry with the given
 primary MAC address or R-bit set to one exists. The protocol type has
 the number prtype. The control bits are set as given in the parameters,
 the LS-bit is set last.
*)
primitive;

function search_entry(prtype : integer; P_MAC_addr : HW_addr_type):
boolean;
(*
 Returns TRUE if an entry with the primary MAC address P_MAC_addr and
 the given protocol type was found in the address cache.
*)
primitive;

procedure update_entry(prtype: integer; P_MAC_addr: HW_addr_type;
 S_MAC_addr: HW_addr_type);
(*
 Searches an entry with the given primary MAC address P_MAC_address and
 updates the secondary MAC address in the entry if the R-bit is set to
 zero.
*)
primitive;

procedure reset_LS_bit(prtype: integer; P_MAC_addr : HW_addr_type);
(*
 Searches an entry with the given primary MAC address P_MAC_address and
 resets the LS-bit if the R-bit is reset.
*)
primitive;

procedure set_Q_bit(prtype: integer; P_MAC_addr : HW_addr_type);
(*
 Searches an entry with the given primary MAC address P_MAC_address and
 sets the Q-bit if the R-bit is reset.
*)
primitive;




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RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


function H_bit_set(prtype: integer; P_MAC_addr : HW_addr_type):
boolean;
(*
 Returns TRUE if an entry exists with H-bit set to one and the given
 P-MAC address.
*)
primitive;

function OR_bit_set(prtype: integer; P_MAC_addr : HW_addr_type):
boolean;
(*
 Returns TRUE if an entry exists with OR-bit set to one and the given
 P-MAC address.
*)
primitive;

function LS_bit_set(prtype: integer; P_MAC_addr : HW_addr_type):
boolean;
(*
 Returns TRUE if an entry exists with LS-bit set to one and the given
 P-MAC address.
*)
primitive;

function Q_bit_set(prtype: integer; P_MAC_addr : HW_addr_type):
boolean;
(*
 Returns TRUE if an entry exists with Q-bit set to one and the given
 P-MAC address.
*)
primitive;

function get_subscript(prtype: integer; P_MAC_addr : HW_addr_type):
integer;
(*
 Returns the subscipt number of an entry with the given primary MAC
 address.
*)
primitive;

function get_broadcast_addr(prtype : integer): PR_addr_type;
(*
 Returns the broadcast protocol address for the given protocol type.
*)

function get_P_MAC_addr(subscript : integer) : HW_addr_type;
(*
 Returns the primary MAC address of the entry with the given subscript



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RFC 1329     Address Resolution for Dual MAC FDDI Networks      May 1992


 number.
*)
primitive;

function get_S_MAC_addr(prtype: integer; P_MAC_addr: HW_addr_type):
 HW_addr_type;
(*
 Returns the secondary MAC address of the station with the given primary
 MAC address.
*)
primitive;

procedure delete_entry(subscript : integer);
(*
 Deletes the entry with the given subscript number if the R-bit is
 reset.
*)
primitive;

function get_pr_type(subscript : integer) : integer;
(*
 Returns the protocol type for the entry with the given subscript
 number.
*)
primitive;

function get_pr_length(prtype : integer) : integer;
(*
 Returns the length of a protocol address.
*)
primitive;


trans

when LS_ARPSAP.UNITDATA_request(Source_addr,Dest_addr,QoS,PDU)
begin
 arp_pdu := extract_arp_pdu(PDU);
 output SNAP1_ARPSAP.UNITDATA_request(Source_addr,Dest_addr,QoS,PDU);
 dmarp_pdu.hwtype               := ethernet;
 dmarp_pdu.prtype               := arp_pdu.prtype;
 dmarp_pdu.HW_length            := fddi_addr_length;
 dmarp_pdu.PR_length            := arp_pdu.PR_length;
 dmarp_pdu.operation            := reply;
 dmarp_pdu.HW_1                 := My_P_MAC_addr;
 dmarp_pdu.HW_2                 := My_S_MAC_addr;
 dmarp_pdu.PR_sender            := arp_pdu.PR_sender;
 dmarp_pdu.PR_receiver          := arp_pdu.PR_receiver;



Kuehn                                                          [Page 21]