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BOOTP/DHCP Parameters

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BOOTP/DHCP Parameters

BOOTP/DHCP Parameters


The Bootstrap Protocol (BOOTP) [RFC951] describes an IP/UDP
bootstrap protocol (BOOTP) which allows a diskless client machine to
discover its own IP address, the address of a server host, and the
name of a file to be loaded into memory and executed.  The Dynamic
Host Configuration Protocol (DHCP) [RFC1531] provides a framework for
automatic configuration of IP hosts.  The "DHCP Options and BOOTP
Vendor Information Extensions" [RFC1533] describes the additions to the
Bootstrap Protocol (BOOTP) which can also be used as options with the
Dynamic Host Configuration Protocol (DHCP).

BOOTP Vendor Extensions and DHCP Options are listed below:

   Tag     Name          Data Length    Meaning          
   ---     ----          -----------    -------          
    0      Pad               0          None     
    1      Subnet Mask       4          Subnet Mask Value
    2      Time Offset       4          Time Offset in
                                        Seconds from UTC
    3      Gateways          N          N/4 Gateway addresses
    4      Time Server       N          N/4 Timeserver addresses
    5      Name Server       N          N/4 IEN-116 Server addresses
    6      Domain Server     N          N/4 DNS Server addresses
    7      Log Server        N          N/4 Logging Server addresses
    8      Quotes Server     N          N/4 Quotes Server addresses
    9      LPR Server        N          N/4 Printer Server addresses
   10      Impress Server    N          N/4 Impress Server addresses
   11      RLP Server        N          N/4 RLP Server addresses 
   12      Hostname          N          Hostname string
   13      Boot File Size    2          Size of boot file in 512 byte
   14      Merit Dump File   N          Client to dump and name
                                        the file to dump it to
   15      Domain Name       N          The DNS domain name of the 
   16      Swap Server       N          Swap Server addeess
   17      Root Path         N          Path name for root disk
   18      Extension File    N          Path name for more BOOTP info

   19      Forward On/Off    1          Enable/Disable IP Forwarding
   20      SrcRte On/Off     1          Enable/Disable Source Routing
   21      Policy Filter     N          Routing Policy Filters
   22      Max DG Assembly   2          Max Datagram Reassembly Size
   23      Default IP TTL    1          Default IP Time to Live
   24      MTU Timeout       4          Path MTU Aging Timeout
   25      MTU Plateau       N          Path MTU  Plateau Table
   26      MTU Interface     2          Interface MTU Size
   27      MTU Subnet        1          All Subnets are Local
   28      Broadcast Address 4          Broadcast Address
   29      Mask Discovery    1          Perform Mask Discovery
   30      Mask Supplier     1          Provide Mask to Others
   31      Router Discovery  1          Perform Router Discovery
   32      Router Request    4          Router Solicitation Address
   33      Static Route      N          Static Routing Table
   34      Trailers          1          Trailer Encapsulation
   35      ARP Timeout       4          ARP Cache Timeout
   36      Ethernet          1          Ethernet Encapsulation
   37      Default TCP TTL   1          Default TCP Time to Live
   38      Keepalive Time    4          TCP Keepalive Interval
   39      Keepalive Data    1          TCP Keepalive Garbage
   40      NIS Domain        N          NIS Domain Name
   41      NIS Servers       N          NIS Server Addresses
   42      NTP Servers       N          NTP Server Addresses
   43      Vendor Specific   N          Vendor Specific Information
   44      NETBIOS Name Srv  N          NETBIOS Name Servers
   45      NETBIOS Dist Srv  N          NETBIOS Datagram Distribution
   46      NETBIOS Note Type 1          NETBIOS Note Type
   47      NETBIOS Scope     N          NETBIOS Scope
   48      X Window Font     N          X Window Font Server
   49      X Window Manmager N          X Window Display Manager
   50      Address Request   4          Requested IP Address
   51      Address Time      4          IP Address Lease Time
   52      Overload          1          Overload "sname" or "file"
   53      DHCP Msg Type     1          DHCP Message Type
   54      DHCP Server Id    4          DHCP Server Identification
   55      Parameter List    N          Parameter Request List
   56      DHCP Message      N          DHCP Error Message
   57      DHCP Max Msg Size 2          DHCP Maximum Message Size
   58      Renewal Time      4          DHCP Renewal (T1) Time
   59      Rebinding Time    4          DHCP Rebinding (T2) Time
   60      Class Id          N          Class Identifier
   61      Client Id         N          Client Identifier
   62      Netware/IP Domain N          Netware/IP Domain Name
   63      Netware/IP Option N          Netware/IP sub Options
   64      NIS-Domain-Name   N          NIS+ v3 Client Domain Name
   65      NIS-Server-Addr   N          NIS+ v3 Server Addresses
   66      Server-Name       N          TFTP Server Name
   67      Bootfile-Name     N          Boot File Name
   68      Home-Agent-Addrs  N          Home Agent Addresses
   69      SMTP-Server       N          Simple Mail Server Addresses
   70      POP3-Server       N          Post Office Server Addresses
   71      NNTP-Server       N          Network News Server Addresses
   72      WWW-Server        N          WWW Server Addresses
   73      Finger-Server     N          Finger Server Addresses
   74      IRC-Server        N          Chat Server Addresses
   75      StreetTalk-Server N          StreetTalk Server Addresses
   76      STDA-Server       N          ST Directory Assistance Addresses
   77      User-Class        N          User Class Information

   78-127  Unassigned
   128-154 Reserved

   255     End               0          None 


[RFC951]  Croft, B., and J. Gilmore, "BOOTSTRAP Protocol (BOOTP)",
          RFC-951, Stanford and SUN Microsytems, September 1985.

[RFC1531]  Droms, R., "Dynamic Host Configuration Protocol", Bucknell
           University, October 1993.   

[RFC1533]  Alexander, S., and R. Droms, "DHCP Options and BOOTP Vendor
           Extensions", Lachman Technology, Inc., Bucknell University,
           October 1993.


Connected: An Internet Encyclopedia
BOOTP/DHCP Parameters