Value,Name,Purpose,Valid for Opcodes,Length,May Appear in,Maximum Occurrences,Reference
0,Reserved,,,,,,[RFC6887]
1,THIRD_PARTY,"Indicates the MAP or PEER request is for a host other
        than the host sending the PCP Option.","MAP, PEER",16 octets,"Request.  May appear in response only if it
        appeared in the associated request.",1,[RFC6887]
2,PREFER_FAILURE,"Indicates that the PCP server should not create an
        alternative mapping if the suggested external port and address
        cannot be mapped.",MAP,0,"Request.  May appear in response only if it
        appeared in the associated request.",1,[RFC6887]
3,FILTER,Specifies a filter for incoming packets.,MAP,20 octets,"Request.  May appear in response only if it
        appeared in the associated request.",As many as fit within maximum PCP message size.,[RFC6887]
4,NONCE,See Section 5.3 of [RFC7652].,AUTHENTICATION,4 octets,Request and response.,1,[RFC7652]
5,AUTHENTICATION_TAG,See Section 5.4 of [RFC7652].,"MAP, PEER, ANNOUNCE",variable,Request and response.,1,[RFC7652]
6,PA_AUTHENTICATION_TAG,See Section 5.5 of [RFC7652].,AUTHENTICATION,variable,Request and response.,1,[RFC7652]
7,EAP_PAYLOAD,See Section 5.6 of [RFC7652].,AUTHENTICATION,variable,Request and response.,1,[RFC7652]
8,PRF,See Section 5.7 of [RFC7652].,AUTHENTICATION,4 octets,Request and response.,As many as fit within maximum PCP message size.,[RFC7652]
9,MAC_ALGORITHM,See Section 5.8 of [RFC7652].,AUTHENTICATION,4 octets,Request and response.,As many as fit within maximum PCP message size.,[RFC7652]
10,SESSION_LIFETIME,See Section 5.9 of [RFC7652].,AUTHENTICATION,4 octets,Response.,1,[RFC7652]
11,RECEIVED_PAK,See Section 5.10 of [RFC7652].,AUTHENTICATION,4 octets,Request and response.,1,[RFC7652]
12,ID_INDICATOR,See Section 5.11 of [RFC7652].,AUTHENTICATION,variable,Response.,1,[RFC7652]
13,THIRD_PARTY_ID,"Together with the THIRD_PARTY option, the
      THIRD_PARTY_ID option identifies a third party
      for which a request for an external IP address
      and port is made.","MAP, PEER",Variable; maximum 1016 octets.,"Request. May appear in response only if it
      appeared in the associated request.",1,[RFC7843]
14-95,Unassigned,,,,,,
96-126,Reserved for Private Use,,,,,,[RFC6887]
127,Reserved,,,,,,[RFC6887]
128,DESCRIPTION,Used to associate a text description with a mapping.,"MAP, PEER","variable, maximum 1016 octets.","Request.  May appear in response only if it
        appeared in the associated request.",1,[RFC7220]
129,PREFIX64,"Learn the prefix used by the NAT64 to build
          IPv4-converted IPv6 addresses. This is used by a host
          for local address synthesis (e.g., when an IPv4 address
          is present in referrals).","MAP, ANNOUNCE",variable,"request, response","1 for a request. As many as fit within
          the maximum PCP message size for a response.",[RFC7225]
130,PORT_SET,To map sets of ports.,MAP,5 bytes,Request and response.,1,[RFC7753]
131-191,Unassigned,,,,,,
192,CHECKPOINT_REQUIRED,Indicate if an entry needs to be check-pointed.,"MAP, PEER",0,Request and response.,1,[RFC7767]
193-223,Unassigned,,,,,,
224-254,Reserved for Private Use,,,,,,[RFC6887]
255,Reserved,,,,,,[RFC6887]