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! d i g i t a l ! I N T E R O F F I C E M E M O R A N D U M
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TO: TOPS20 Monitor Meeting List
DATE: November 13, 1978
FROM: Larry Campbell
DEPT: DEC20 S. E. Dept.
LOC: MR1-2/E37
EXT: 6877
DISTRIBUTED: November 29, 1978 FILE: EXLEAD.MEM
REVIEWED: December 11, 1978 PDM #: DLC-78-001-03-U
SUBJ: Extended leaders in TOPS20AN
In releases prior to Release 4, TOPS20AN used the old
format IMP/Host protocol (BBN Report No. 1822). This protocol
allows 6 bits to specify the destination IMP, and 2 bits to
specify the host on the particular IMP. This allows only 63
IMPs on the ARPANET (IMP 0 does not exist). The IMP/Host
protocol was extended some time ago to allow 16 bits to specify
the destination IMP, and 8 bits to specify the host on the
particular IMP. Both protocols are currently in use on the
ARPANET, but since the 64th IMP has been added to the network,
hosts using the old protocol will not be able to communicate
with new hosts as they come on the network. Also, at some time
in the future, support for the old protocol will be dropped.
Because of this, support is being added to TOPS20AN for the new
protocol. This memo documents the changes visible to the user
as a result of this work.
Because there can now be an extremely large number of
hosts on the network ((2**16-1)*(2**8)), it is no longer
possible to index GETAB tables by host number. To ease the
conversion, all old GETAB tables will be simulated in Release
4, but will only work for hosts with numbers which fit into the
old protocol fields. Hence, programs which use the old GETABs
will only know about hosts on IMPs numbered 1 through 63. In
order to effectively communicate with all hosts on the network,
two new JSYSes have been added.
To: TOPS20 Monitor Meeting List Page 2
Subj: Extended leaders in TOPS20AN
GTHST% JSYS 273
Obtains information about Arpanet hosts.
Accepts in AC1: Function code
AC2:
AC3: Function dependent
AC4:
Returns +1: Failure, error in AC1
+2: Host number in AC3, Host status in AC4
Function Symbol
code
0 .GTHSZ
AC2: Returns -number of host names,,0
AC3: Returns -length of HSTSTS table,,0
AC4: local host number, in 32-bit Internet format
1 .GTHIX
AC2: Destination byte pointer (updated)
AC3: Index into name table
Returns the name string with the given index. If the name
returned is a nickname, HS%NCK is on in the status word.
2 .GTHNS
AC2: Destination byte pointer (updated)
AC3: Host number
Returns the primary name for the given host number.
3 .GTHSN
AC2: Source byte pointer (updated)
Translates the host name string given to its host number.
Also return the host's current status. If the name given
was a nickname then HS%NCK will be on in the status word.
4 .GTHHN
AC3: Host number
Return the current status of the given host.
To: TOPS20 Monitor Meeting List Page 3
Subj: Extended leaders in TOPS20AN
5 .GTHHI
AC3: Index into HSTSTS
Returns the host number and status of the host with the
given index into the host status table.
GTHST ERROR MNEMONICS:
ARGX02: Invalid function
GTHSX1: Unknown host number
GTHSX2: No number for that host name
GTHSX3: No string for that Host number
GTJIX1: Invalid index
Bits in host status word
Symbol Value Meaning
HS%UP 1B0 HOST IS UP
HS%VAL 1B1 VALID STATUS
HS%DAY 7B4 DAY WHEN UP IF DOWN
HS%HR 37B9 HOUR
HS%MIN 17B13 5 MIN INTERVAL
HS%RSN 17B17 REASON
HS%SRV 1B18 HOST IS SERVER
HS%USR 1B19 HOST IS USER
HS%NCK 1B20 NICKNAME
HS%STY 77B26 SYSTEM TYPE MASK
HS%NEW 1B27 RAS,RAR,RAP ETC
.HS10X 1B26 TENEX
.HSITS 2B26 ITS
.HSDEC 3B26 TOPS-10
.HSTIP 4B26 TIP
.HSMTP 5B26 MTIP
.HSELF 6B26 ELF
.HSANT 7B26 ANTS
.HSMLT 10B26 MULTICS
.HST20 11B26 TOPS-20
.HSUNX 12B26 UNIX
To: TOPS20 Monitor Meeting List Page 4
Subj: Extended leaders in TOPS20AN
GTNCP% JSYS 272
Obtains information about the NCP.
Accepts in AC1: Function code
AC2:
AC3: Function dependent
AC4:
Returns +1: Failure, error in AC1
+2: Data returned in block
The following functions are implemented. Each returns a
block of data on an NCP connection at the address pointed to
by AC3, except for .GTNSZ which is used to obtain the size
and starting connection index. AC4 is updated by the number
of words returned.
Function Symbol
code
0 .GTNSZ
AC2: -number of NCP connections,,0
AC3: -number of NVTs ,, line number of first NVT
1 .GTNIX
AC2: Connection number
AC3: 30 bit address of block to store data
AC4: -Length of block,,First data item to return
2 .GTNNI
AC2: NVT Line number (input connection)
AC3: 30 bit address of block to store data
AC4: -Length of block,,First data item to return
3 .GTNNO
AC2: NVT Line number (output connection)
AC3: 30 bit address of block to store data
AC4: -Length of block,,First data item to return
4 .GTNJF
AC2: JFN
AC3: 30 bit address of block to store data
AC4: -Length of block,,First data item to return
GTNCP ERROR MNEMONICS:
ARGX02: Invalid function
To: TOPS20 Monitor Meeting List Page 5
Subj: Extended leaders in TOPS20AN
GTJIX1: Invalid index
GTNCX1: Invalid network JFN
GTNCX2: Invalid or inactive NVT
Offsets into the data block:
Word Symbol Meaning
0 .NCIDX NCP CONNECTION INDEX
1 .NCFHS FOREIGN HOST
2 .NCLSK LOCAL SOCKET
3 .NCFSK FOREIGN SOCKET
4 .NCFSM STATE OF CONNECTION
5 .NCLNK LINK
6 .NCNVT NVT, -1 IF NONE
7 .NCSIZ BYTE SIZE OF CONNECTION
10 .NCMSG MSG ALLOC
11 .NCBAL BIT ALLOC
12 .NCDAL DESIRED ALLOC
13 .NCBTC BITS XTERRED
14 .NCBPB BYTES/BUFFER
15 .NCCLK TIME-OUT COUNTDOWN
16 .NCSTS CONNECTION STATUS
This project will not change the command-level user
interface of TOPS20AN; all utilities will continue to work
just as well (or poorly) as they have in the past. All old
functionality in the JSYS interface will continue. Users will
be able to initiate, use, and terminate network connections
just as they have in the past, using the standard file-system
JSYSes. In order to address new network hosts, however,
programs will need to make use of the new JSYSes.
Applicable standards:
o IMP/Host Protocol (BBN Report No. 1822)
o Host/Host Protocol (NIC 7104)
o TOPS20 Coding Standards (CSTAND.MEM)
[End of EXLEAD.MEM]